JP2005349729A - Liquid tank, method for manufacturing the liquid tank, and liquid discharge recording apparatus on which the liquid tank is mounted - Google Patents

Abstract

To provide an ink tank that can be used in two postures and can stably supply a large amount of ink while having a simple configuration with high ink storage efficiency and use efficiency. .
In the ink tank, an ink supply port and an air communication port are formed, and a negative pressure generating member storage chamber is provided in which negative pressure generating members (11a, 11b) that absorb and hold ink (15) are stored. The ink storage chamber 27 directly holding the ink 15 is partitioned by a partition wall 14 having a communication portion. The negative pressure generating member 11b has an angle of 90 ° as a surface in contact with the liquid flowing in from the communicating portion, and is positioned horizontally when supplying ink in different usage postures. First and second gas introduction surfaces 20a and 20b that function to introduce gas are formed.
[Selection] Figure 1

Description

  The present invention relates to an ink tank (liquid tank) for storing a liquid (hereinafter simply referred to as ink) such as ink to be supplied to an ink jet recording head (liquid discharge recording head), and an ink jet recording apparatus in which the ink tank is mounted ( Liquid discharge recording apparatus).

  In general, an ink tank used in the ink jet recording field is for adjusting the holding force of ink stored in the ink tank in order to satisfactorily supply ink to a recording head for discharging ink. It has a configuration. This ink holding force is called negative pressure because it is for making the pressure of the ink discharge portion of the recording head negative with respect to the atmosphere.

  As a means for easily generating this holding force, a method of impregnating a porous material such as polyurethane foam with ink is well known. By using such a method, the ink absorber 111 made of a porous material is accommodated in the housing as in the example of the ink tank 101 shown in FIG. 20A, and the ink is held in the ink absorber 111. An ink tank having a simple configuration is obtained.

  With reference to FIG. 20, the ink tank 101 of this example will be described in a little more detail. The casing of the ink tank 101 is composed of a case 102 and a lid 103 that closes the opening surface thereof. The space in the casing holds ink and acts to apply negative pressure to the ink supplied to the recording head. An ink absorber 111 is accommodated. As the ink absorber 111, it is known to use a fiber entangled body in addition to a porous body or a foam, and the ink is filled in the void, thereby causing a capillary force to act on the ink. Capillary force is used as a holding force for ink.

  An ink supply port 110 that is an opening for supplying ink to the outside is formed at the bottom of the case 102. In addition, a cylindrical portion 113 that communicates with the ink supply port 110 is formed at the bottom of the case 102, and a capillary force is applied to the cylindrical portion 113 from the ink absorber 111 in order to stably supply ink. An ink lead-out member 112 that is strong and has high physical strength is provided.

  A handle portion forming member 150 is attached to the lid 103 in order to facilitate the operation of attaching and removing the ink tank 101 to the ink jet recording apparatus. The handle portion forming member 150 is formed with an atmosphere communication port 108 b for communicating the atmosphere with the inside of the housing through the atmosphere communication port 108 a provided in the lid 103. Further, a protrusion or rib 124 is formed on the inner surface side of the lid 103, and the rib 124 abuts on the upper surface of the ink absorber 111, so that the ink absorber 111 exists on the lower surface of the formation portion of the atmosphere communication port 108a. An unused space 125 is secured. This space 125 functions as a buffer space that functions to prevent ink leakage from the atmosphere communication port 108a.

  As shown in FIGS. 20B and 20C, the ink tank 101 is detachably mounted on a recording head unit 102 mounted on a carriage that performs main scanning during ink jet recording. It is done. For this purpose, the carriage is provided with a portion that detachably supports the ink tank 101, and this portion is called a tank holder 154.

  The tank holder 154 is provided with a supply pipe 152 for connecting the recording head unit 102 and the ink lead-out member 112 disposed at the ink supply port 111 of the ink tank 101. A filter 153 is disposed at the tip of the supply pipe 152, and a seal member 151 is provided at a portion of the tank holder 154 that comes into contact with the periphery of the ink supply port 111 so that the ink is not leaked. It has been.

  As shown in FIG. 20B, the ink tank 101 is inserted into the tank holder 154 while being rotated, and is fixed as shown in FIG. 20C. For the purpose of positioning and stable fixing, the ink tank 101 and the tank holder 154 are provided with engaging portions that engage with each other, but are not shown.

  As can be seen from the drawing, the ink lead-out member 112 provided at the bottom of the ink tank 101 is pushed up to the ink absorber 111 side by the supply pipe 152 at the time of mounting. As a result, the ink absorber 111 is slightly compressed in the vicinity of the ink lead-out member 112. By the compression, the capillary force of the compressed portion of the ink absorber 111 is increased, and the ink is easily collected in this portion. Accordingly, it is possible to stably supply ink without entraining air on the supply side, and it is possible to reduce ink remaining in the ink absorber 111, that is, to improve the use-up property of the ink. .

  Although it is a rare example for a printer equipped with such an ink tank, as shown in FIG. 21 (a), even if it is placed so as to have a relatively low height (flat placement), FIG. As shown in (b), those that can be used even in a state where the width is relatively narrow (vertical placement) have been put to practical use. FIG. 21 schematically shows an ink tank 951 mounted on a carriage supported so as to be reciprocally movable along the carriage guide shaft 952 in this printer. As can be seen from this drawing, the ink tank 951 is shown in FIG. In this case, it is used in a posture different by 90 ° between the case where it is placed horizontally and the case where it is placed vertically. That is, for example, when the ink tank 101 shown in FIG. 20 is installed, when installed in a flat position, as shown in FIG. 20A, the ink supply port 110 is positioned downward and the atmosphere communication port 108a is positioned upward. On the other hand, when placed horizontally, as shown in FIG. 20 (d), the ink supply port 110 and the atmosphere communication port 108a are used in a state where they face sideways.

  In the ink tank 101 configured to generate a negative pressure by the capillary force of the ink absorber 111, the negative pressure in both the horizontal and horizontal orientations of the printer, and the change in the negative pressure from the initial stage to the end of use can be obtained. Although there is a slight difference, because of the negative pressure generation principle, it is possible to supply ink while applying a negative pressure even if it is used in a posture different by 90 ° as described above. Further, as a printer with the ink tank 101 mounted and in a single use posture, as shown in FIG. 20A, the ink tank 101 is mounted in a posture in which ink is consumed in the direction of gravity. What is configured is generally used, but what is configured so that the ink tank 101 is mounted from the beginning in the posture shown in FIG.

  On the other hand, the applicant of Patent Document 1 discloses that the ink storage efficiency and the use of ink can be supplied to the ink tank as described above by using an ink absorber with a negative pressure. We have proposed a simple ink tank with high reliability and high reliability.

  FIG. 22 shows a schematic cross-sectional configuration diagram of the ink tank 201 having such a configuration. The inside of the ink tank 201 is divided into two sections by a partition wall 214 having a communication part 209. One section is substantially sealed except for the communication portion 209 of the partition wall 214 and is an ink storage chamber 227 that directly stores the ink 215. The other compartment is an ink absorber housing chamber 228 that houses the ink absorber 232. An air communication port 208 for introducing the atmosphere into the ink tank 101 as the ink is consumed, and a recording head unit (not shown) for supplying ink to the wall surface forming the ink absorber housing chamber 228. An ink supply port 210 is formed.

  In the illustrated example, the communication portion 209 is formed with an air introduction groove 250 that extends upward from the upper end of the through hole of the communication portion 209 on the ink absorber chamber 228 side. The atmosphere introduction groove 250 functions to promote introduction of the atmosphere into the ink storage chamber 227 side. In addition, a space (buffer chamber) 225 without the ink absorber 232 is secured by the rib 124 in the vicinity of the atmosphere communication port 208 of the casing of the ink tank 201.

  In FIG. 22, the area of the ink absorber 232 that holds the ink 215 is indicated by a hatched portion. That is, the ink absorber 215 is formed with a gap capable of generating a capillary force. In the lower part of the ink absorber 215, the ink 215 is filled in the lower part, and in the upper part, the inside of the gap is mainly used. It is filled with the atmosphere, and a gas-liquid interface 223 is formed as a boundary between these portions. In FIG. 22, the area where the ink 215 is directly stored is indicated by a mesh portion.

  In the structure described above, when the ink 215 of the negative pressure generating member 232 is consumed by a recording head (not shown), the gas-liquid interface 223 eventually becomes the upper end of the communication portion 209, as shown in FIG. It reaches the position of the line 251 where the upper end of the air introduction groove 250 and the ink absorber 232 contact each other. When the ink 215 is further consumed from this state, the air introduced into the ink absorber housing chamber 228 from the air communication port 208 with the subsequent ink consumption enters the ink housing chamber 227 through the communication portion 209 of the partition wall 214. . Instead, the ink 215 is filled from the ink storage chamber 227 into the ink absorber 232 in the ink absorber storage chamber 228 via the air introduction groove 250 provided in the partition wall 214 and the communication portion 209. This series of operations is hereinafter referred to as a gas-liquid exchange operation.

  Since this gas-liquid exchange operation is performed, even if ink is consumed by the recording head, the ink absorber 232 is filled with ink according to the amount consumed, and the ink absorber 232 holds a certain amount of ink. (The position of the gas-liquid interface 223 is maintained). Thereby, the ink absorber 232 keeps the negative pressure on the recording head substantially constant, that is, stable ink supply to the recording head is ensured.

  An ink tank capable of realizing such downsizing and high use efficiency has been commercialized by the present applicant and is still in practical use. At this time, such an ink tank 201 can be used only in a predetermined posture (including a slight inclination of the printer installation location) in order to perform a predetermined gas-liquid exchange operation.

Further, the present applicant has proposed an ink tank using a fiber made of an olefin-based resin having thermoplasticity as a negative pressure generating member of the ink tank as described above in Patent Document 2. This ink tank has excellent ink storage stability, and also has excellent recyclability because the ink tank casing and the fiber material are made of the same material.
Japanese Patent No. 2951818 JP-A-8-20115

  In recent years, ink jet recording technology has made great progress, and it has become possible to easily obtain an output with an image quality comparable to that of a photograph by improving the recording pixel density and miniaturizing the recording droplets. On the other hand, the life of the recording head has been extended to the same extent as that of the printer, and it is no longer necessary to replace the recording head before the end of the life of the printer. Therefore, if the user replenishes only the ink tank and paper, the print output can be continuously obtained.

  However, in conventional printers, if the printer series is different, it is generally necessary to use different configurations and forms of ink tanks together with the printer and recording head even if the actual ink used is exactly the same. It was the target. This is because manufacturers that want to provide attractive printers have different ink tank shapes that can be accommodated in the specified space without greatly restricting the layout space for other mechanisms. Is a cause. In addition, it is necessary to use the ink tank in a predetermined posture, which is a cause of the necessity to change the configuration of the ink tank for each printer model. In other words, conventionally, ink tanks have basically been determined to have a desired supply performance, ink useability, and various reliability (especially reliability against ink leakage due to changes in the use environment) except for the determined posture. There is no technology that can maintain almost the same performance in posture. As a result, even if the size of the space in which the ink tank is arranged is approximately the same, for example, the length in the vertical direction as shown in FIG. Short ink tanks are required, and as shown in FIGS. 23B and 23C, ink tanks having ink storage chambers for directly storing ink also need to be vertically long and horizontally long. These ink tanks are not compatible.

This situation feels very inconvenient from the user's point of view. In other words, “I bought a new printer, but I want to continue using the ink tank that has been used up to this point without wasting it” or “Use multiple printers of different models at home or at work. However, it is necessary to prepare a plurality of spare ink tanks, and it takes a lot of space, labor, and money, and it will be difficult if each color is aligned. Thus, if one set of spare ink tanks is prepared, it is desired that a plurality of printers be able to replace the ink tanks. " (First issue)
In addition, as described above, the ink tank having the configuration in which only the ink absorber gap is used for accommodating the ink as shown in FIG. 20 can be mounted and used in different postures in such different types of printers. However, such an ink tank is disadvantageous in terms of ink storage efficiency and ink use efficiency as compared with an ink tank having an ink storage chamber for directly storing ink as shown in FIG. is there. Therefore, it can be used in different postures, has a simple structure, has high ink storage efficiency, and high ink use efficiency, and is used at the time of distribution or use after opening or after being opened and removed from the printer. There is a need for an ink tank with high reliability. (Second problem)
Furthermore, there are the following problems in terms of ink supply performance.

  That is, in recent years, in the ink jet recording apparatus, the recording speed has been increased, and accordingly, the ink supply amount per unit time from the ink tank to the ink jet head tends to increase. As a result, in the ink tank 101 as shown in FIG. 20, when the amount of ink supplied is larger than that assumed for the ink tank 101, the ink passes through the ink absorber 232. The generated flow resistance increases drastically, and coupled with the increase in the flow resistance generated by the filter 153, the negative pressure in the recording head increases, and normal ejection may be difficult.

  Further, when the ink tank 201 shown in FIG. 22 is used, when the ink supply amount increases more than expected for the ink tank 201, the air corresponding to the ink supply amount catches up with the ink storage chamber 227. For this reason, the gas-liquid interface 223 in the ink absorber 232 is lowered, and the negative pressure in the recording head also varies. If the ink supply amount further increases, the ink supply is interrupted, that is, the ink runs out, even though the ink remains in the ink storage chamber 227.

  The mechanism of the ink out in the conventional ink tank 201 will be described in more detail with reference to FIG. As in the conventional ink jet recording apparatus, when the ink supply amount from the ink tank 201 is a relatively small amount as expected, as described above, the gas-liquid interface 223 in the ink absorber 232 causes the gas-liquid exchange operation. Accordingly, the upper end of the air introduction groove 250 and the line 251 where the ink absorber 232 is in contact with each other as shown in FIG. This is because the amount of ink led out from the ink storage chamber 227 and the amount of air introduced into the ink storage chamber 227 accordingly are balanced.

  On the other hand, when the ink supply amount increases more than expected, the gas-liquid interface 223 decreases as shown in FIG. This is because the introduction of air into the ink storage chamber 227 that matches the ink supply amount cannot catch up. That is, from the ink storage chamber 227 side, as the air is introduced, ink corresponding to the air amount is replenished to the ink absorber 223, but the ink supply amount exceeds the replenishment amount. Accordingly, the ink is supplied supplemented with the ink held in the ink absorber 232, the amount of ink held in the ink absorber 232 is reduced, and the gas-liquid interface 223 is lowered (operation A). .

  As the gas-liquid interface 223 is lowered, the ink absorber 232 is positioned above the gas-liquid interface 223 in the portion of the ink absorber 232 that is in contact with the air introduction groove 250, and therefore, most of the gap is filled with air. The area of the area spreads in the vertical direction. This region functions as a gas introduction surface through which air can pass from the ink absorber 232 into the ink storage chamber 227, and this gas introduction surface is when the gas-liquid interface 223 is at the upper end position of the communicating portion 209. The amount of air introduced into the ink storage chamber 227 per unit time increases by spreading in the vertical direction from the state of a part or the entire area of the line 251 (operation B). As a result, due to the balance between the operation A and the operation B, the gas-liquid interface 223 is lowered, thereby expanding the gas introduction surface and increasing the amount of air introduced into the ink storage chamber 227 per unit time. It stops at a position where the amount becomes equal to the ink supply amount, and thereafter, the gas-liquid interface 223 is maintained at this position while the ink supply is continued. Thereafter, when the ink supply amount decreases or when the ink supply is stopped, the gas-liquid interface 223 gradually returns to the normal position shown in FIG.

  At this time, if the gas-liquid interface 223 is lowered, this also causes an increase in the negative pressure in the recording head unit, which may change the ink discharge conditions from the ink jet recording head and cause a disorder in the recording operation. In addition, when the ink supply amount is increased to 3 times, 5 times, or 10 times (10 to 20 ml / min), the ink supply chamber 227 is reduced even if the gas-liquid interface 223 is lowered. The air introduction amount is not balanced with the ink supply amount, and as shown in FIG. 22C, the gas-liquid interface 223 reaches the ink supply port 110, and the ink is stored in the ink storage chamber. The ink cannot be supplied, and there is a possibility that the phenomenon of running out of ink may be caused.

Therefore, in the conventional configuration, even if the amount of ink supply increases in the future, in order to prevent such a drop in the gas-liquid interface 223 or ink outage, the ink tank is made large and the gas introduction surface is increased. It will be necessary to enlarge it. However, for this purpose, there is a problem that it is necessary to provide a larger mounting space in the recording apparatus. Therefore, it is desired to provide an ink tank having higher supply performance without changing the size of the ink tank. ing. (Third issue)
SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and the object thereof is to maintain stable ink supply performance and high reliability even if the mounting posture is different, that is, the operation posture of the ink tank is different (first). In addition, the ink storage efficiency and use efficiency are high with a simple configuration (second problem), and it is possible to realize high ink supply performance that has not been obtained so far, which can cope with higher speed ink jet recording. (The third problem), a liquid tank, and a liquid discharge recording apparatus on which the liquid tank is mounted (the ink does not run out and the increase in flow resistance is suppressed and stable ink supply can be performed).

  The part that introduces air into the liquid storage chamber during the gas-liquid exchange is defined as the gas introduction surface. However, it is the applicant of the present application that the gas introduction surface operates in such a manner as to increase the ink supply property while spreading in the vertical direction. It is added that this has been clarified for the first time in the process of studying to solve the above problems.

  In order to achieve the above object, a liquid tank according to the present invention includes a liquid supply port for supplying liquid to a liquid discharge recording head, an air communication port, and a liquid tank for holding liquid supplied to the liquid discharge recording head. A negative pressure generating member storage chamber that stores a negative pressure generating member that absorbs and holds the liquid, and a liquid storage chamber that directly holds the liquid. The chamber is partitioned by a partition wall formed with a communication portion for communicating the two, the liquid storage chamber is substantially sealed except for the communication portion, and the negative pressure generating member is in contact with the liquid flowing in from the communication portion. The surface is characterized by having at least two surfaces that form a predetermined angle with each other.

  According to this configuration, when the liquid tank is used in two usage postures, in each posture, one of the two surfaces of the negative pressure generating member that are in contact with the liquid flowing in from the communication portion and that form a predetermined angle with each other, In the gas-liquid exchange operation, it can function as a gas introduction surface for introducing air into the liquid storage chamber.

  The method for manufacturing a liquid tank according to the present invention includes a supply port for supplying a liquid to a liquid discharge recording head, and an air communication port communicating with the atmosphere, and a negative pressure generating member containing a negative pressure generating member that absorbs and holds the liquid A storage chamber, a negative pressure generation member storage chamber that communicates with the negative pressure generation member storage chamber, and is substantially sealed except for the communication portion, and stores a liquid, and the negative pressure generation member storage chamber and the liquid storage chamber except for the communication portion In the method for manufacturing a liquid tank, the two portions that are horizontal in two use postures that are 90 degrees different from each other in the portion corresponding to the communicating portion of the negative pressure generating member. A step of providing a surface, a step of inserting a negative pressure generating member provided with two surfaces into the negative pressure generating member storage chamber of the liquid tank, and each of the two usage postures of the liquid storage container. From the horizontal surface In the area of even without the negative pressure generating member positioned above up to the negative pressure generating member located below, characterized in that it comprises a step of holding the filling liquid.

  According to the present invention, in the liquid tank that has the liquid storage chamber and the negative pressure generating member storage chamber, and thus has a simple configuration, the storage efficiency and the use efficiency can be increased. In the gas-liquid exchange operation, one of the two surfaces of the negative pressure generating member that are in contact with the liquid flowing in from the communicating portion and having a predetermined angle functions as a gas introduction surface that introduces air into the liquid storage chamber Thereby, good ink supply operation can be performed in both postures. Further, in this liquid tank, the surface functioning as a gas introduction surface for introducing air into the liquid storage chamber can be positioned substantially horizontally in the in-use posture, whereby the gas-liquid exchange operation The efficiency of gas introduction into the liquid storage chamber at the time can be improved, and stable large-capacity ink supply can be achieved.

Embodiments of the present invention will be described below with reference to the drawings. In the following embodiments, ink is described as an example of the liquid supplied to the recording head of the present invention. However, the applicable liquid is not limited to ink, and for example, in the ink jet recording field. Needless to say, it includes a treatment liquid for the recording medium. In each cross-sectional view of the ink tank, the ink absorber, that is, the negative pressure generating member, the area holding the ink is indicated by the shaded area, and the area where the ink is directly stored in the space is indicated by the meshed line. ing. In addition, each cross-sectional view of the ink tank shows not only a static state but also consumption of ink in the negative pressure generating member has progressed, and ink has been consumed from the ink storage chamber (gas-liquid replacement). It also includes an indication of the condition.
(First embodiment)
FIG. 1 is a schematic cross-sectional view of an ink tank 1 according to a first embodiment of the present invention. The ink tank 1 has a thin flat shape in the width direction, and FIG. 1 is perpendicular to the width direction. It is sectional drawing cut | disconnected by the plane. In this way, the ink tank 1 having a flat shape thin in the width direction is suitable for mounting a plurality of ink tanks 1 containing inks of a plurality of colors in the width direction and mounting them on the carriage of the recording apparatus. Further, as can be seen from FIG. 1, in the ink tank 1, the shape of the cross section perpendicular to the width direction is a rectangular shape having a relatively large difference in vertical and horizontal sizes. As will be apparent from the following description, the ink tank 1 is arranged in a state that is long in the horizontal direction and low in height as shown in FIG. 1A (also called a horizontal posture or a standard posture). 1), and the ink supply operation shown in FIG. 1 (b) is high even if it is arranged so as to be short in the horizontal direction and rotated 90 ° with respect to the horizontal posture (vertical posture). It has a configuration that can.
(Ink tank configuration)
First, the configuration of the ink tank 1 will be described in detail. Here, for convenience, terms such as “up and down” are used in the description with reference to the state of the standard posture.

  The casing of the ink tank 1 is composed of a case 2 and a lid 3 that covers an opening on the upper surface thereof. In the ink tank 1, a negative pressure generating member storage chamber 26 in which two negative pressure generating members 11a (capillary force weak) and 11b (strong capillary force) having different capillary forces are stacked and accommodated on the upper side and the lower side, respectively. The partition wall 14 partitions the ink storage chamber 27 (liquid storage chamber) 27 that directly stores and stores the liquid ink 15. In the partition wall 14, a communication portion 9 is formed in the vicinity of the bottom of the ink tank 1 to connect the negative pressure generating member storage chamber 26 and the ink storage chamber 27. The contact surfaces 41 of the two negative pressure generating members 11 a and 11 b are located above the upper end of the communicating portion 9. The partition wall 14 protrudes horizontally toward the negative pressure generating member accommodating chamber 26 at the vertical portion 14a extending vertically downward so as to partition the negative pressure generating member accommodating chamber 26 and the ink accommodating chamber 27, and at the lower end of the vertical portion 14a. It has a horizontal portion 14b extending in the shape of L and is L-shaped as a whole. A communication portion 9 is formed between the lower surface of the horizontal portion 14 b and the bottom surface of the ink tank 15.

  The ink storage chamber 27 is substantially sealed except for the communication portion 9. On the other hand, the negative pressure generating member accommodating chamber 26 communicates with the atmosphere through the atmosphere communication port 8 at the upper portion, and when attached to a recording apparatus (not shown), the side surface (the left side surface of FIG. ) Communicates with the ink supply port (liquid supply port) 10. In the negative pressure generating member accommodating chamber 26, a rib 24 formed on the lid 3 is in contact with the upper surface of the negative pressure generating member 11a accommodated in a compressed state around the atmosphere communication port 8, thereby A buffer chamber 25 in which the generating member 11a does not exist is secured. The ink supply port 10 is located within the height range where the negative pressure generating member 11b exists, and the capillary force is stronger between the negative pressure generating member 11b and the ink supply port 10 than the negative pressure generating member 11b. The ink lead-out member 12 having a high physical strength is disposed. The ink lead-out member 12 is disposed so as to be in pressure contact with the wall surface of the negative pressure generating member accommodating chamber 26 and the negative pressure generating member 11b and in direct contact with the ink 15 accommodated in the ink accommodating chamber 27, that is, the ink tank 1. A portion extending toward the communication portion 9 is provided along the bottom surface.

  In the present embodiment, the negative pressure generating member 11b has an outer shape that is significantly different from that shown in FIG. That is, the lower part of the surface of the negative pressure generating member 11b on the side of the communication part 9 is retracted from the inner surface position of the vertical part 14a of the partition wall 14 on the negative pressure generating member storage chamber 26 side, The portion that has entered the inside and the portion above the portion that has entered enters the overhanging portion 11 c that extends to the partition wall 14. A hanging portion 11d extending to the upper surface of the horizontal portion 14b of the partition wall 14 is formed below the protruding portion 11c on the partition wall 14 side along the vertical portion 14a of the partition wall 14. Accordingly, the negative pressure generating member 11b is a U-shaped portion as a whole at the portion communicating with the communication portion 9, and the negative pressure generating member 11b has a U-shape in the negative pressure generating member accommodating chamber 26. A portion surrounded by the shape and the communication portion 9 is a space 5a into which the ink 15 in the ink storage chamber 27 can directly flow.

  In the space 5a, a reflecting prism 13a having a surface facing the outer surface of the ink tank 1 and a surface facing the space 5a is disposed at the bottom of the ink tank 1. The reflecting prism 13a detects the remaining amount of the ink 15 by utilizing the change in the amount of reflection of light incident from the outside depending on whether or not the ink 15 is in contact with the surface facing the space 5a. It is a member used for. As can be understood from FIGS. 1A and 1B, the lower region of the space 5a is absorbed by the negative pressure generating members 11a and 11b or the ink lead-out member 12 both in the horizontal position and in the vertical position. Instead, it is located at the bottom of the ink 15 in a directly stored state. Therefore, by using the reflecting prism 13a disposed in the space 5a, it is properly detected that the ink 15 in the directly stored state is almost lost in both the horizontal posture and the vertical posture. can do.

In this embodiment, the lower surface of the projecting portion 11c of the negative pressure generating member 11a extends horizontally, and the side surface of the hanging portion 11d facing the negative pressure generating member accommodation chamber 26 side extends vertically. These surfaces are, as will be described later, a first gas introduction surface 20a for introducing gas into the ink storage chamber 27 when the ink tank 1 is used in the horizontal posture and the vertical posture, respectively, and during the gas-liquid exchange operation. It functions as the second gas introduction surface 20b.
(Material of negative pressure generating member)
Here, the material of the negative pressure generating members 11a and 11b will be touched. As a material, various capillary bodies made of a porous body such as foamed polyurethane or a fiber material can be used. If fiber materials are used, the degree of freedom of material selection is greater than that of porous materials such as urethane, so it is possible to select materials with better ink wettability and excellent ink wettability. An ink tank can be provided. Further, by selecting a thermoplastic resin or a material of the same material as the ink tank main body as the fiber material, an ink tank excellent in recyclability can be provided. In addition, by selecting a fiber material with a core-sheath configuration using two types of materials having different melting points as the fiber material, the intersection of the fibers can be reliably fixed by thermal bonding, so that the ink holding force (capillary force) is It is possible to provide an ink tank that is stable and has stable ink holding characteristics, that is, negative pressure characteristics. In this embodiment, as the negative pressure generating members 11a and 11b, fiber materials made of an olefin-based resin having a core part made of polypropylene and a sheath part made of polyethylene are aligned and thermoformed. This utilizes the difference between the melting points of polypropylene and polyethylene, and the temperature during thermoforming is set between the melting point of the low melting point material and the melting point of the high melting point material (for example, higher than the melting point of polyethylene, polypropylene The lower melting point of the fiber material can be used as an adhesive, and the intersection of the fibers can be easily fixed by melting the polyethylene in the sheath portion having a relatively low melting point. Ink tanks having excellent characteristics as in the present invention are preferred because they are convenient above.
(Ink supply operation in the horizontal position)
Next, the ink supply operation in the horizontal posture (standard posture) will be described with reference to FIGS.

  FIG. 2A shows a state before the ink tank 1 is used before the ink storage chamber 27, the negative pressure generating members 11a and 11b, and the ink outlet member 12 are filled with the ink 15. The ink 15 is filled up to the liquid level indicated by the gas-liquid interface 23 a in the negative pressure generating member 11 a, and the region 11 e above it is a negative pressure generating member region that does not hold the ink 15. If the ink supply to the recording head (not shown) is continued through the ink supply port 10, the liquid level becomes lower. At this time, due to the difference in capillary force between the negative pressure generating members 11a and 11b, the gas-liquid interface is temporarily brought into contact with the negative pressure generating members 11a and 11b as indicated by reference numeral 23b in FIG. 41 is in a horizontal state. Thereafter, when ink is further supplied, the gas-liquid interface eventually becomes the bottom surface of the overhanging portion 11c of the negative pressure generating member 11b, that is, the first gas introduction surface 20a, as indicated by reference numeral 23c in FIG. The height is just above the position.

  When ink is supplied slightly from this state, the gas-liquid interface is lowered, the meniscus of the substantially horizontal first gas introduction surface 20a is broken, and the ink storage chamber 27 is entered as shown in FIG. Atmospheric air is taken in, and instead, the ink 15 in the ink storage chamber 27 is filled into the negative pressure generating member 11b through the communication portion 9 and the space 5a (operation C). The filled ink is supplied to the recording head via the ink lead-out member 12 and the ink supply port 10, and a small amount of ink 15 re-forms a meniscus on the first gas introduction surface 20a, thereby introducing the atmosphere. Stop (operation D). Therefore, even if the ink is supplied, as long as the ink 15 is present in the ink storage chamber 27, the operation C and the operation D are repeated little by little, and the gas-liquid interface in the negative pressure generating member storage chamber 26 is shown in FIG. As a result, a substantially constant negative pressure acts on the supplied ink 15 by the negative pressure generating member 11b, and the ink can be stably supplied to the recording head. .

  FIG. 3B shows a state in which the ink 15 is consumed in this way and the liquid level of the ink 15 in the ink storage chamber 27 is lower than that of the first gas introduction surface 20a. In this state, since the air below the first gas introduction surface 20a is air, bubbles rising in the ink 15 as shown in FIG. 3A are not observed, but the gas-liquid exchange operation is performed without any problem. Is called.

  In addition, an important point for the present invention is that even if ink consumption has progressed such that the ink liquid level in the liquid storage chamber 27 is positioned below the gas introduction surface 20a (see FIG. 3B). ), The ink quickly reaches the gas introduction surface 20a through the negative pressure generating member 11b, and the meniscus of the gas introduction surface 20a that has been in a broken state (the gas introduction path for gas-liquid exchange is in an open state) is quickly regenerated ( The gas introduction path for gas-liquid exchange is closed). In particular, a fiber entangled body that generates a predetermined capillary force, particularly a fiber entangled body made of a polyolefin resin typified by polyethylene or polypropylene, has a higher absorption rate than a foam that generates the same capillary force. More preferred.

When the ink supply is further continued and the ink in the ink storage chamber 27 is almost exhausted, it is detected that the ink storage chamber 27 is emptied by the reflecting prism 13 arranged at the bottom. Thereafter, the maximum ink amount that can be supplied is substantially the ink amount held in the region below the gas-liquid interface indicated by 23d of the negative pressure generating member 11b. That is, as shown in FIG. 3C, after the ink storage chamber 27 is emptied, the ink 15 held in the negative pressure generating member 11b and the ink outlet member 12 is supplied, and finally, As shown in FIG. 4, the ink supply can be continued until the ink 15 is almost used up.
(Ink supply operation in vertical position)
Next, the ink supply operation in the vertical posture will be described with reference to FIGS.

  FIG. 5 shows a state before the start of use of the same ink tank 1 containing the same amount of ink 15 as in the horizontal posture shown in FIG. Even in the vertical posture, due to the difference in capillary force between the negative pressure generating members 11a and 11b, the ink 15 fills the entire negative pressure generating member 11b side, and the air is generated in the negative pressure generating member 11a as indicated by 23p. A liquid interface is formed. That is, the region 11e above the gas-liquid interface indicated by 23p of the negative pressure generating member 11a is a region that does not hold the ink 15.

  When the ink 15 is supplied to the recording head (not shown) through the ink supply port 10, the gas-liquid interface in the negative pressure generating member 11a is lowered. The difference in height between the upper end of the negative pressure generating member 11b and the gas-liquid interface in the negative pressure generating member 11a corresponds to the capillary force difference between the negative pressure generating members 11a and 11b, as shown in FIG. Until the gas-liquid interface in the negative pressure generating member 11a is lowered to the height indicated by 23q, which is the water head difference H, the ink supply is performed without decreasing the gas-liquid interface on the negative pressure generating member 11b side.

  When the gas-liquid interface in the negative pressure generating member 11a is lower than the height indicated by 23q, the gas-liquid interface is lowered in both the negative pressure generating members 11a and 11b. At this time, the difference in height of the gas-liquid interface between the negative pressure generating members 11a and 11b is maintained at the above-described height H.

  Then, as shown in FIG. 6B, the gas-liquid interface in the negative pressure generating member 11b eventually becomes the bottom surface in this vertical posture of the hanging portion 11d of the negative pressure generating member 11b as indicated by 23s. It reaches the vicinity of the second gas introduction surface 20b. At this time, the gas-liquid interface in the negative pressure generating member 11a is at a position indicated by 23r by a height H lower than 23s.

  When the ink 15 is supplied slightly from this state, the gas-liquid interface in the negative pressure generating members 11a and 11b is lowered, and the meniscus of the substantially horizontal second gas introduction surface 20b is broken in this vertical posture. As shown in (a), air is taken into the ink storage chamber 27, and instead, the ink 15 in the ink storage chamber 27 is filled into the negative pressure generating member 11b via the communication portion 9 and the space 5a ( Operation E). The filled ink 15 is supplied to the recording head via the ink lead-out member 12 and the ink supply port 10, and a small amount of ink 15 re-forms a meniscus on the second gas introduction surface 20 b to introduce the atmosphere. Is stopped (operation F). Therefore, even if the ink supply is continued thereafter, as long as the ink 15 exists in the ink storage chamber 27, the operation E and the operation F are repeated little by little, and the gas-liquid interface is positioned at the positions 23r and 23s shown in FIG. Almost never changes. The small repetition of the actions E and F is performed in the same manner as the small repetitions of the actions C and D in the horizontal posture. Therefore, ink can be stably supplied to the recording head with a substantially constant negative pressure.

  FIG. 7B shows a state in which the ink supply is further continued and the liquid level of the ink 15 that is directly held is lower than the second gas introduction surface 20b. In this state, since the air below the second gas introduction surface 20b is air, bubbles rising in the ink 15 as shown in FIG. 7A are not observed, but the gas-liquid exchange operation is performed without any problem. Is called.

  At this time, the meniscus is re-formed in the same manner as described above. That is, one of the important points for the present invention is that even if the ink consumption has progressed so that the ink liquid level in the liquid storage chamber 27 is positioned below the gas introduction surface 20b (FIG. 7B). )), The ink quickly reaches the gas introduction surface 20b through the vertical surface 20a of the negative pressure generating member 11b, and the gas introduction surface 20b that has been in a broken state (the gas introduction path for gas-liquid exchange is in an open state) The meniscus is quickly regenerated (the gas introduction path for gas-liquid exchange is closed). In particular, a fiber entangled body that generates a predetermined capillary force, particularly a fiber entangled body made of a polyolefin resin typified by polyethylene or polypropylene, has a higher absorption rate than a foam that generates the same capillary force. More preferred.

When the ink supply is further continued through the state of FIG. 7B and the directly held ink 15 is almost lost, the ink 15 directly held by the reflecting prism 13 is lost even in this vertical posture. Can be detected. Thereafter, the maximum amount of ink that can be supplied is the amount of ink held in the region below the height indicated by 23r of the negative pressure generating member 11a and the region below the height indicated by 23s of the negative pressure generating member 11b. . That is, as shown in FIG. 8A, after the directly held ink 15 runs out, the ink 15 held in the negative pressure generating members 11a and 11b and the ink outlet member 12 is supplied, and finally In particular, as shown in FIG. 8B, the ink supply can be continued until these inks 15 are almost used up.
(High supply performance)
Next, a mechanism will be described in which the configuration of the present embodiment acts so as not to run out of ink even when the ink supply amount is increased and to suppress an increase in flow resistance.

  In the configuration of the present embodiment, as can be seen with reference to FIGS. 3A and 7A, the meniscus formation surface (gas introduction surfaces 20a and 20b) that switches the introduction of the atmosphere at the time of gas-liquid exchange in any posture. ) Means that the ink tank is almost horizontal in use and is substantially parallel to the ink liquid surface, and therefore the meniscus force in the first or second gas introduction surface 20a or 20b. Is almost constant. For this reason, when the gas-liquid interface is lowered as the ink 15 is supplied, the area of the gas introduction surface is increased as the gas-liquid interface is lowered as in the conventional configuration described with reference to FIG. Unlike these, in these first and second gas introduction surfaces 20a and 20b, the meniscus is destroyed one after another without waiting for the gas-liquid interface to further decrease, and a gas introduction surface having a large area is secured at a stretch. The Accordingly, air can be efficiently introduced into the ink storage chamber 27. As a result, the gas-liquid interface in the negative pressure generating member 11b is greatly below the gas introduction surfaces 20a and 20b. Can be suppressed. Therefore, fluctuations in the generated negative pressure due to the negative pressure generating member 11b can be suppressed, and ink shortage due to the gas-liquid interface reaching the vicinity of the ink supply port 10 can be suppressed.

  The difference between the conventional configuration described with reference to FIG. 22 and the configuration of the present embodiment will be further described. In the conventional configuration, the gas introduction surface to the ink storage chamber is in the vertical direction and the capillary force is increased. In contrast to this, in the configuration of this embodiment, the first or second gas introduction surface 11a, 11b is substantially horizontal, and the capillary force on the surface is substantially uniform. For this reason, in the conventional configuration, even in the state where the gas introduction surface having the same area as that in the present embodiment is secured, the gas introduction in the present embodiment is more efficient.

As a result of conducting an experiment on the ink tank 1 of the present embodiment with the conditions such as the size being substantially the same as those of the conventional one, according to the ink tank 1 of the present embodiment, it is 5 to 10 times the conventional one. Even with respect to the ink supply amount, the ink could be supplied without running out of ink. More specifically, in an ink tank having a width of 8 mm, if the length of the overhanging portion 11 c is about 4 mm and the area of the gas introduction surface 20 a is about 30 mm ² , for example, even if the supply performance is 10 times (10 ml / min). As a result of many verification experiments, it was found that it can be pulled out sufficiently.
(Flow resistance reduction effect)
According to the configuration of the present embodiment, the resistance component related to gas-liquid exchange is greatly reduced compared to the conventional case. Therefore, the flow resistance component at the time of ink supply is reduced to the conventional low value even at the time of supplying a large amount of ink. It has also been found that it is possible to suppress the flow rate as much as possible. This is schematically shown in FIG.

The graph of FIG. 9 represents the negative pressure at the recording head ejection port when ink is supplied to the ink jet recording head. The vertical axis includes dynamic negative pressure (total negative pressure) including the flow resistance during ink supply, The horizontal axis represents the total consumption of ink supplied from the ink tank. In the figure, P ₀ indicates a negative pressure in the recording head portion in a state where ink is not supplied, that is, a static negative pressure. The static negative pressure P ₀ gradually increases in the initial stage of ink supply as the gas-liquid interface in the negative pressure generating member decreases. Thereafter, the static negative pressure P ₀ is kept constant while the gas-liquid interface in the negative pressure generating member is kept constant by the gas-liquid exchange operation. Thereafter, the directly held ink disappears and the gas-liquid interface in the negative pressure generating member begins to fall again, so that the static negative pressure gradually increases again.

P ₁ indicates the negative pressure in the recording head section during ink supply, that is, the total negative pressure when the ink tank of the present embodiment is used, and the distribution of resistance components related to ink flow resistance and gas-liquid exchange. , R ₁ is stronger than the static negative pressure P ₀ .

P ₃ indicates the total negative pressure when an ink tank having a conventional configuration is used. The results shown in FIG. 9 are for the case where the ink supply amount per unit time is increased as compared with the conventional case. For this reason, in the conventional configuration, the negative pressure generating member even after the gas-liquid exchange operation is started. The gas-liquid interface at the bottom is lowered, so that the total negative pressure continues to increase gradually. In the conventional configuration, the gas-liquid interface finally reaches the ink supply port, the ink supply is interrupted, and the ink out phenomenon is caused.

P ₂ indicates the total negative pressure when it is assumed that the ink supply amount is suppressed to such an extent that ink is not run out when an ink tank having a conventional configuration is used. Compared to the flow resistance component R ₂ in this case, the flow resistance component R ₁ in the case of the present embodiment is drastically suppressed, i.e., high to suppress the increase of the negative pressure than conventional ink tank A flow rate of ink supply can be realized. As described above, in the ink tank 1 having the configuration of the present embodiment, the gas introduction surface 20a or 20b having a relatively large area can be secured at a stretch. Therefore, unlike the conventional ink tank, the negative pressure generating member The gas-liquid interface does not decrease in the inside, and the capillary force is almost uniform over the entire gas introduction surface, so that a large amount of air corresponding to the amount of ink derived can be controlled with less resistance than in the conventional configuration. This is because it can be promptly introduced into the ink containing chamber.

  In this embodiment, when the mounting posture is changed by changing the ink tank 1 to a printer with a different mounting posture in the middle of use or the like, the ink pressure in the negative pressure generating members 11a and 11b is changed according to the posture change. Movement (of course, the gas-liquid interface also moves) and some gas-liquid exchange accompanying it may occur. However, if the configuration is set such that the areas of the gas introduction surfaces 20a and 20b are substantially equal so that the ink supply performance in both postures is substantially the same, the posture change is performed at any stage during use. However, this does not impair the reliability or decrease the ink supply performance.

Although not mentioned in the present embodiment, each of the negative pressure generating members 11a and 11b and the ink outlet member 12 and the inner wall of the negative pressure generating member accommodating chamber 26 including the partition wall 14 are surely connected. Providing ribs or the like as appropriate so as to be in close contact is an auxiliary means effective in the present invention. The space 5a, the overhanging portion 11c, and the hanging portion 11d may be configured so as to ensure substantially horizontal gas introduction surfaces 20a and 20b sufficient for supply performance, and are not limited to the illustrated configuration. At this time, it is also effective to configure so as not to hinder the rapid movement of the bubbles generated from the gas introduction surfaces 20a and 20b to the ink storage chamber 27. That is, for example, as shown in FIG. 4, the negative pressure generating member accommodating chamber 26 of the end surface of the horizontal portion 14b of the partition wall 14 on the negative pressure generating member accommodating chamber 26 side and the hanging portion 11d of the negative pressure generating member 11b. The position of the side surface, that is, the second gas introduction surface 20b may be shifted by G1, and this difference G1 can be allowed from a negative dimension to a positive dimension and can be set as appropriate.
(Second Embodiment)
FIG. 10 is a schematic cross-sectional view of the ink tank 1 according to the second embodiment of the present invention, and (a) and (b) show a horizontal posture and a vertical posture, respectively. The basic configuration of the ink tank 1 of the present embodiment is the same as that shown in the first embodiment, but the configuration of the partition wall 14 is slightly different. That is, in the first embodiment, the partition wall 14 is provided with a horizontal portion so that it wraps around in an L shape below the surface 11f that is the low surface in the horizontal posture of the hanging portion 11d of the negative pressure generating member 11b. However, in the present embodiment, this horizontal portion is not provided.

  FIGS. 11 to 13 show the ink supply operation when the ink tank 1 of the present embodiment is used in the horizontal posture. Although details are omitted, the ink supply operation in the horizontal posture is the same as in the first embodiment. That is, as the ink 15 is consumed, the gas-liquid interface is lowered from the state where the gas-liquid interface exists in the negative pressure generating member 11a (FIG. 11A), and the gas-liquid interface generates negative pressure. After aligning with the contact surfaces 41 of the members 11a and 11b (FIG. 11 (b)), it reaches the vicinity of the first gas introduction surface 20a (FIG. 11 (c)). Thereafter, when the ink 15 is further consumed, a gas-liquid exchange operation is performed (FIG. 12A), and the gas-liquid interface is the first gas introduction surface 20a until the directly retained ink 15 disappears. (FIGS. 12B and 12C). Thereafter, the ink in the negative pressure generating members 11a and 11b and the ink outlet member 12 is consumed, and the ink 15 in the ink tank 1 is used up (FIG. 13). By such an operation, the same effect as described in the first embodiment can be obtained.

  In the case of the vertical posture, the surface 11f serving as the bottom surface in the horizontal posture of the hanging portion 11d of the negative pressure generating member 11b is prior to the gas introduction surface 20b having a substantially horizontal large area starting to act as a gas introduction surface. Thus, it begins to act as a substantially vertical gas introduction surface. When the ink supply amount is large, as in the prior art, the introduction of gas from the surface 11f acting as a substantially vertical gas introduction surface into the ink storage chamber 27 is not in time, and the negative pressure generating member 11b is not in time. A drop in the gas-liquid interface occurs. However, after the gas-liquid interface reaches the second gas introduction surface 20b in this way, the efficient gas introduction from the second gas introduction surface 20b is performed as in the first embodiment. As a result, further reduction of the gas-liquid interface can be suppressed, and thus the effect of the present invention can be obtained, which enables stable supply of a large volume of ink. At this time, while the gas-liquid interface is lowered to the position of the second gas introduction surface 20b in the negative pressure generating member 11b, the negative pressure fluctuates. This fluctuation of the negative pressure generating member 11b There is a slight time lag from the start of the gas-liquid exchange operation until the gas-liquid interface reaches the second gas introduction surface 20b. Does not occur. Further, unlike the prior art, there is no fear that the gas-liquid interface will be lowered and the supply negative pressure will not be stable, and the ink will run out.

Therefore, according to the configuration of the present embodiment, substantially the same effects as those of the first embodiment can be obtained while the configuration is simpler than that of the first embodiment.
(How to wear both vertical and horizontal postures)
Here, the configuration of the mounting portion of the ink jet recording apparatus to which the ink tank 1 described in the first or second embodiment is mounted will be described with reference to FIG.

  FIGS. 14A and 14B are diagrams showing an example of mounting on a vertically placed printer having a small depth as an ink jet recording apparatus. Although not shown in detail, this printer has a carriage supported so as to be able to reciprocate on a recording medium to be conveyed, and an ink tank 1 is provided with a tank holder 54 provided on the carriage. Mounted on.

  As can be seen from FIGS. 14A and 14B, the ink tank 1 is mounted on the tank holder 54 while being rotated. The outer surface of the casing of the ink tank 1 and the tank holder 54 can be provided with engaging portions (not shown) that are engaged with each other and used for positioning and stable fixing. The tank holder 54 is provided with a supply cylinder 52 connected to the ink supply port 10 of the ink tank 1, and the supply cylinder 52 communicates with an ink jet recording head unit 70 that is a mechanism for discharging ink to perform recording. Yes. A filter 53 that functions to prevent bubbles and foreign matter from entering the recording head unit 70 is disposed at the tip of the supply cylinder 52. In addition, a seal member 51 is disposed around the supply cylinder 152 so as to abut against a portion around the ink supply port 10 of the ink tank 1 and to prevent ink leakage and air intrusion. Further, a through hole 60 is formed in the tank holder 54 at a position facing the reflecting prism 13 provided in the ink tank 1 in a state where the ink tank 1 is mounted, and light is transmitted to the printer through the through hole 60. A light irradiation / detection mechanism 61 is provided that detects the amount of light reflected from the reflection prism 13 through the reflection prism 13. Based on the detection signal of the light irradiation / detection mechanism 61, it can be determined that the ink directly held in the ink tank 1 has almost disappeared.

  In the case of the vertical printer with a small depth shown in FIGS. 14A and 14B, as can be understood from the drawing, the ink tank 1 is adapted to easily take up a space in the vertical direction in the printer. Used in a vertical posture. On the other hand, FIG. 14C is a diagram showing an example of mounting on a thin flat printer having a low height. In this case, the ink tank 1 can easily take a relatively large space in the printer in the horizontal direction. To be used, it is mounted and used in a horizontal posture. In the example shown in FIG. 14C, the tank holder 54 including the arrangement of the recording head unit 70 has the same configuration as that shown in FIGS. 14A and 14B except for the orientation. Yes. Therefore, parts can be shared between the vertical printer and the horizontal printer. At this time, the ink ejection direction from the recording head unit 70 is downward in the configuration of FIGS. 14A and 14B, whereas it is horizontal in the configuration of FIG. Although the conditions are slightly different, regarding ink supply, if ink supply with substantially the same negative pressure is performed, good ink discharge is possible. Therefore, according to the present invention, the same ink tank 1 can be used in common in both printers, and at the same time, as described above, the ink storage chamber is also provided, the ink storage efficiency is high, and stable ink supply is possible. An effect is also obtained.

For example, as shown in FIG. 15, the tank holder 54 can be changed as appropriate, for example, in the case of a flat printer, the recording head unit 70 is configured to eject ink downward. . In addition, as a method of mounting the ink tank 1 to the tank holder 54, a configuration in which the ink tank 1 is mounted while rotating is shown. However, the configuration is not limited to this. For example, a configuration in which the ink tank 1 is mounted by sliding may be used. Of course, it is possible to adopt a configuration in which the mounting method differs between the case of the flat printer and the case of the flat printer.
(Third embodiment)
FIG. 16 is a cross-sectional view showing the configuration of the ink tank 1 according to the third embodiment of the present invention. FIG. 16A shows that the gas-liquid exchange operation is performed in the vertical posture, and FIG. 16B shows that the gas-liquid exchange operation is performed in the horizontal posture.

  The ink tank 1 of the present embodiment is different in position of the ink supply port 10 from that of the first embodiment, and is disposed at a position directly below the negative pressure generating member 11b on the bottom surface in the horizontal posture. . Accordingly, the ink lead-out member 12 is provided only on the bottom surface portion in the horizontal posture state. Other configurations are the same as those of the first embodiment.

  In the configuration of this embodiment, the same ink supply operation as that of the first embodiment is performed, and the same effect as that of the first embodiment is obtained.

The ink supply port 10 may be disposed obliquely at the corner of the ink tank 1, and in this case, the ink supply port 10 is at an angle of 45 ° both in the vertical position and in the horizontal position. It can be made to face diagonally downward.
(Fourth embodiment)
FIG. 17 shows a variation of the configuration of the negative pressure generating member and the ink lead-out member as the fourth embodiment of the present invention. That is, in the configuration shown in FIG. 17A, the ink lead-out member is omitted. In the configuration shown in FIG. 17B, there is only one negative pressure generating member indicated by reference numeral 11. In the configuration shown in FIG. 17C, the ink lead-out member is omitted and only one negative pressure generating member is provided. Compared to these configurations, the configuration of the above-described embodiment is advantageous in terms of the function of leveling the gas-liquid interface and the function of easily guiding the ink to the ink supply port portion, but FIG. ) To (c), the effect of the present invention that can stably supply a large amount of ink in any of the vertical and horizontal positions can be obtained.

In particular, in the configuration shown in FIG. 17C, when the recording apparatus is mounted, the negative pressure generating member 11 is strongly compressed by inserting the supply pipe connected to the ink supply port 10 into the ink tank 1. It is desirable to have a configuration. Thereby, the capillary force of the negative pressure generating member 11 in the vicinity of the ink supply port 10 is increased so that the ink is efficiently collected on the ink supply port 10 side, and air passes through the ink supply port 10. It is possible to stabilize the ink supply by suppressing this. Even if this configuration is applied to the configurations of FIGS. 17A and 17B and the first and second embodiments, an effective operation can be obtained. Also, as shown in FIGS. 17B and 17C, when only one negative pressure generating member 11 is used, it is difficult to cause a difference in performance between both postures by using a foam such as polyurethane foam. Can do.
(Fifth embodiment)
FIG. 18 is a schematic cross-sectional view of an ink tank 1 for explaining a fifth embodiment of the present invention. In the configuration of the present embodiment, the shape of the negative pressure generating member 11b is different from that of the second embodiment. That is, in the second embodiment, the negative pressure generating member 11b is formed with a hanging portion at the tip of the overhanging portion 11c, and has a U-shape as a whole. The portion is omitted, and the negative pressure generating member 11b is L-shaped as a whole.

  Even with this relatively simple configuration, the effects of the present invention can be obtained. That is, first, in the horizontal posture state shown in FIG. 19 (a), the first gas introduction surface 20a, which is the bottom surface of the negative pressure generating member 11c in the horizontal posture state, causes air to flow during the gas-liquid exchange operation. The ink supply chamber 27 functions to be introduced into the ink storage chamber 27. Therefore, the same ink supply operation as in the first and second embodiments can be obtained. On the other hand, in the case of the horizontal posture shown in FIG. 19B, the surface 20c extending from the base portion of the negative pressure generating member 11a toward the wall surface of the ink tank 1 acts as the second gas introduction surface. In the fourth embodiment, the second gas introduction surface 20 c is substantially horizontal when the ink tank 1 is in the vertical posture. The second gas introduction surface 20a has a difference that the second gas introduction surface in the second embodiment is upward as opposed to the second gas introduction surface in the second embodiment. The operating principle itself introduced to the chamber 27 side is not different from that in the second embodiment.

  Therefore, also in the present embodiment, as in the first and second embodiments, in the gas-liquid exchange operation, the gas is efficiently ejected by the action of the gas introduction surfaces 20a and 20c positioned almost horizontally in each posture. The effect of the present invention is introduced into the storage chamber 27, thereby suppressing a decrease in the gas-liquid interface in the negative pressure generating member 11 b and capable of stably supplying a large amount of ink in any of the vertical and horizontal postures. Is obtained.

  However, also in the present embodiment, in the vertical posture, it is necessary to pay attention to the fact that the first gas introduction surface 20a starts to act as a vertical air introduction surface at the start of the gas-liquid exchange operation. Therefore, when the ink supply amount is relatively large, the gas-liquid interface in the negative pressure generating members 11a and 11b is positioned relative to the positions 23r-1 and 23s-1 when the gas-liquid exchange operation starts. 23r-2 and 23s-2 are generated, and then the gas-liquid interface is stably maintained at this position by the action of the second gas introduction surface 20c. At this time, after the gas-liquid exchange operation is started, while the gas-liquid interface is lowered in the negative pressure generating members 11a and 11b, until the stable gas-liquid exchange operation by the action of the second gas introduction surface 20c is started. Furthermore, considering the negative pressure fluctuation and the time lag, the length of the overhanging portion 11c of the negative pressure generating member 11b (vertical posture shown in FIG. 11B) is set so as not to increase. It is preferable to set the height at a suitable value.

  In each of the above embodiments, the ink tank 1 having a long shape in the direction in which the negative pressure generating member storage chamber 26 and the ink storage chamber 27 are arranged is shown. This configuration is advantageous in that the vertical printer with a shallow depth and the horizontal printer with a low height are mounted with their postures changed by 90 °, and both the vertical posture and the horizontal posture of the present invention are used. Thus, the effect of enabling good ink supply is utilized, but the present invention is not limited to such a configuration. That is, the present invention can be suitably applied without detracting from the effect of the present invention, whether it has a sufficient thickness in the width direction or a shape close to a cube. Various variations can be considered for the shape of the communicating portion 9 portion of the negative pressure generating member. However, in order to minimize the amount of ink remaining in any of different postures, or to make it possible to commonly use the remaining ink amount detecting means. In addition, the negative pressure generating member divides the region in which ink is directly stored and the region in which the ink is held and stored in the negative pressure generating member in both horizontal and vertical directions. It is desirable to have a configuration.

  Finally, we will touch on the proper ink filling amount and filling state. First, as shown in FIGS. 1A and 1B, the ink is stored in the ink storage chamber 27 and the negative pressure generating member storage chamber 26 almost completely in the initial state (use start state) of the ink tank 1. It is in a state filled with. If not satisfied, the air present in the unfilled area 11e of the negative pressure generating member accommodating chamber or the buffer space 25 is replaced with the ink held in the negative pressure generating member, and unintended air is contained in the ink. May flow into the room. Desirably, the ink may be held in the negative pressure generating member region above the surface that is horizontally disposed in the use posture among the two surfaces. In addition, in an ink tank in which negative pressure generating members having different capillary forces are stacked and accommodated in a vertical direction in one use posture, the first and It is desirable to fill the ink in such an amount that the ink is held over the entire interface of the pressure contact portion of the second negative pressure generating member. By filling in this way, air existing in the unfilled region 11e of the negative pressure generating member storage chamber or the buffer space 25 is held by the negative pressure generating member in the flow process after the ink tank is manufactured and used. It is possible to prevent unintended air from flowing into the ink containing chamber and replacing the ink with the negative pressure generating member region.

2A and 2B are schematic cross-sectional views of the ink tank according to the first embodiment of the present invention, in which FIG. 1A shows a standard posture (horizontal posture) and FIG. 1B shows a vertical posture. It is a figure explaining the supply operation in the horizontal attitude | position of the ink tank of FIG. It is a figure explaining the supply operation in the horizontal attitude | position of the ink tank of FIG. It is a figure explaining the supply operation in the horizontal attitude | position of the ink tank of FIG. It is a figure explaining the supply operation | movement with the vertical attitude | position of the ink tank of FIG. It is a figure explaining the supply operation | movement with the vertical attitude | position of the ink tank of FIG. It is a figure explaining the supply operation | movement with the vertical attitude | position of the ink tank of FIG. It is a figure explaining the supply operation | movement with the vertical attitude | position of the ink tank of FIG. 2 is a graph for explaining the flow resistance reduction effect of the ink tank of FIG. 1. FIG. 10 is a schematic cross-sectional view of an ink tank according to a second embodiment of the present invention, in which FIG. 10A shows a standard posture (horizontal posture) and FIG. 10B shows a vertical posture. It is a figure explaining the supply operation | movement with the horizontal attitude | position of the ink tank of FIG. It is a figure explaining the supply operation | movement with the horizontal attitude | position of the ink tank of FIG. It is a figure explaining the supply operation | movement with the horizontal attitude | position of the ink tank of FIG. FIGS. 14A and 14B are views for explaining mounting of the ink tanks of FIGS. 1 and 10 to the ink jet recording apparatus, FIGS. 14A and 14B are mounted in a vertical position, and FIG. 14C is mounted in a horizontal position. Show. It is a figure which shows the other example of mounting | wearing with the horizontal attitude | position of the ink tank of FIG. FIG. 16 is a schematic cross-sectional view of an ink tank according to a third embodiment of the present invention, in which FIG. 16A shows a vertical posture and FIG. 16B shows a standard posture (horizontal posture). It is a schematic sectional drawing of the ink tank of the 4th Embodiment of this invention. It is a schematic sectional drawing of the ink tank of the 5th Embodiment of this invention, Fig.18 (a) has shown the normal attitude | position (horizontal attitude), FIG.18 (b) has shown the vertical attitude | position. FIGS. 19A and 19B are diagrams illustrating an ink tank supply operation of FIG. 18, in which FIG. 19A illustrates a standard posture (horizontal posture), and FIG. 19B illustrates a vertical posture. It is a schematic sectional drawing of the ink tank of a prior art example. It is a figure explaining the mounting state to the inkjet recording device of the ink tank of FIG. It is a schematic sectional drawing of the ink tank of another prior art example. It is a schematic sectional drawing of the ink tank of another prior art example.

Explanation of symbols

1 Ink tank (liquid tank)
8 Air communication port 9 Communication unit 10 Ink supply port (liquid supply port)
11, 11a, 11b Negative pressure generating member 14 Partition 15 Ink (liquid)
20a, 20b Gas introduction surface (two surfaces forming a predetermined angle with each other)
26 Negative pressure generating member storage chamber 27 Ink storage chamber (liquid storage chamber)

Claims (16)

In the liquid tank that holds the liquid supplied to the liquid discharge recording head,
A liquid supply port for supplying a liquid to the liquid discharge recording head and an air communication port, and a negative pressure generating member storage chamber for storing a negative pressure generating member for absorbing and holding the liquid; A liquid storage chamber for directly holding
The negative pressure generating member storage chamber and the liquid storage chamber are partitioned by a partition wall formed with a communication portion that communicates both, and the liquid storage chamber is substantially sealed except for the communication portion,
The liquid tank, wherein the negative pressure generating member has a shape having at least two surfaces forming a predetermined angle with each other as a surface in contact with the liquid flowing in from the communication portion.   The liquid tank is used in a first posture and a second posture, and each of the two surfaces of the negative pressure generating member is horizontally disposed in one of the first posture and the second posture. The liquid tank according to claim 1.   3. The liquid tank according to claim 1, wherein ink is held up to a negative pressure generating member region above a surface of the two surfaces that is horizontally disposed in a use posture. 4. Liquid tank.   4. The liquid tank according to claim 1, wherein the capillary force at each arbitrary portion of each surface is substantially uniform on each of the two surfaces facing the liquid storage chamber. 5. The negative pressure generating member storage chamber stores first and second negative pressure generating members that are in pressure contact with each other,
The capillary force of the first negative pressure generating member is higher than the capillary force of the second negative pressure generating member,
Abutting surfaces of the first and second negative pressure generating members extend in a direction intersecting the partition;
The first negative pressure generating member communicates with the communicating portion, communicates with the liquid supply port, and communicates with the atmosphere communicating hole only through the contact surface;
The second negative pressure generating member can communicate with the communication portion only through the contact surface,
The contact surfaces of the first and second negative pressure generating members are horizontal in the posture of the two surfaces of the negative pressure generating member in one of the first posture and the second posture. 5. The liquid tank according to claim 2, wherein the liquid tank is located above the surface arranged at the top.   The liquid tank according to claim 5, wherein an upper end of the communication portion is positioned below the contact surfaces of the first and second negative pressure generating members.   7. The liquid tank according to claim 5, wherein the ink is applied over the entire area of the interface between the pressure contact portions of the first and second negative pressure generating members, regardless of the posture in use, including the posture during use of the liquid tank. Liquid tank characterized by being held.   The liquid tank according to claim 1, wherein an angle formed by the two surfaces of the negative pressure generating member is 90 °.   The negative pressure generating member has an overhanging portion extending to a position in contact with the partition wall at a position above the upper end of the communication portion when viewed in a posture in which the communication portion is positioned vertically below the liquid tank. 9. The shape according to claim 1, wherein the projecting portion has a U-shaped shape including a hanging portion that extends downward along the partition wall from a position where the projecting portion abuts on the partition wall. Liquid tank.   The liquid tank is used in a first posture and a second posture, and the negative pressure generating member is a region in which the liquid is directly stored in any of the two use postures; 10. The liquid tank according to claim 1, wherein the liquid tank has a shape that divides a region in which the liquid is held by the negative pressure generating member and accommodated in a substantially horizontal direction and a substantially vertical direction. In the liquid tank that holds the liquid supplied to the liquid discharge recording head,
A liquid supply port for supplying a liquid to the liquid discharge recording head and an air communication port, and a negative pressure generating member storage chamber for storing a negative pressure generating member for absorbing and holding the liquid; A liquid storage chamber for directly holding
The negative pressure generating member storage chamber and the liquid storage chamber are partitioned by a partition wall formed with a communication portion that communicates both, and the liquid storage chamber is substantially sealed except for the communication portion,
When the liquid in the negative pressure generating member is consumed, air is introduced from the atmosphere communication port into the negative pressure generating member accommodating chamber, enters the liquid accommodating chamber through the communicating portion, and the introduced air Instead, the negative pressure generating member of the negative pressure generating member accommodating chamber is filled with the liquid in the liquid accommodating chamber through the communication portion, and at this time, air from the negative pressure generating member accommodating chamber to the liquid accommodating chamber is filled. The liquid tank is characterized in that the introduction is performed on a substantially horizontal surface of the negative pressure generating member.   The liquid tank according to claim 1, wherein the negative pressure generating member is made of a fiber material. A supply port for supplying liquid to the liquid discharge recording head, and an air communication port communicating with the atmosphere, and a negative pressure generating member housing chamber containing a negative pressure generating member for absorbing and holding the liquid;
A liquid storage chamber for storing a liquid, which communicates with the negative pressure generating member storage chamber and is substantially sealed except for the communication portion;
In a method for manufacturing a liquid tank, comprising: a partition wall that partitions the negative pressure generating member storage chamber and the liquid storage chamber except for the communication portion;
Providing two surfaces that are respectively horizontal in two usage postures of the liquid storage container that are 90 degrees different from each other in the portion corresponding to the communication portion of the negative pressure generating member;
Inserting a negative pressure generating member provided with two surfaces into the negative pressure generating member accommodating chamber of the liquid tank;
In each of the two usage postures of the liquid storage container, a region from the negative pressure generating member positioned at least above the horizontal surface of the two surfaces to the negative pressure generating member positioned below. And a step of filling and holding the liquid. It is a manufacturing method of the liquid tank according to claim 13,
Preparing a first negative pressure generating member;
A second negative pressure generating member having a capillary force lower than that of the first negative pressure generating member is prepared, and a portion corresponding to the communicating portion of the negative pressure generating member is used in the use posture of the liquid storage container. Providing a horizontal cutout, and
Storing the first and second negative pressure generating members in the negative pressure generating member storage chamber so as to be in pressure contact with each other. It is a manufacturing method of the liquid tank according to claim 14,
Filling any amount of liquid that can hold the liquid over the entire area of the interface between the pressure contact portions of the first and second negative pressure generating members, regardless of the posture in which the liquid tank is used. A method for manufacturing a liquid tank.   A liquid discharge recording head for discharging the liquid supplied from the liquid tank, wherein the liquid tank according to any one of claims 1 to 15 or a liquid tank obtained by a method for manufacturing a liquid tank is mounted. A liquid discharge recording apparatus.

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