JP2006123562A - Ink cartridge and inkjet printer - Google Patents

Abstract

To prevent ink color mixture of ink cartridges in which inks of various colors are filled in a plurality of ink chambers in which a movable lid is lowered as ink is consumed, and to prevent foreign matter from entering the ink.
The ink chambers 13 (1) to 13 (4) of the ink cartridge 10 are hermetically sealed by an ink meniscus formed in a gap 37 between a movable lid 33 that can be raised and lowered and a circumferential surface 31 a of the ink chamber. 35 is formed, and ink is supplied to the outside from the ink reservoir 35 via the ink take-out part 15. Even if an impact or the like is applied and ink flows out from the gap 37 to the back side of the movable lid 33, the back side portion is partitioned into independent spaces 38 for each ink chamber by the partition plate 20. Does not occur. Since the outflowed ink is not in contact with the ink absorber 17 in the waste ink chamber 14, foreign matter is not mixed in, so there is no problem even if the ink returned to the ink storage part 35 through the gap 37 is used again.
[Selection] Figure 5

Description

  The present invention relates to an ink cartridge including a plurality of ink chambers configured such that a movable member descends as ink is consumed, and more specifically, the back surface of the movable member in each ink chamber when an impact is applied due to dropping or the like. The present invention relates to an ink cartridge that can prevent color mixture of ink that has flowed out to the side and leakage of the ink to the outside. The present invention also relates to an ink jet printer using such an ink cartridge as an ink supply source.

  As ink cartridges for inkjet printers, a flexible ink bag filled with ink is stored in a rigid plastic case, and a foam or felt that absorbs and holds ink is stored in a rigid plastic case. A foam-type ink tank having the above-described configuration is known. However, the bag-type ink tank and the foam-type ink tank have a problem that the extraction efficiency of the filled ink is poor. In addition, since the ink filling efficiency with respect to the entire capacity is low, there is a problem that it is difficult to reduce the size of the ink tank. Further, in the bag type ink tank, there is a risk of ink leakage due to ink seal failure of the ink bag, ink leakage due to tearing of the ink bag due to rubbing between the ink bag and the plastic case in which it is stored during transportation. . In order to prevent rubbing and tearing, it is only necessary to increase the rigidity and strength of the flexible material constituting the ink bag. However, in this case, the negative pressure for supplying ink increases, Detrimental effects such as an increase in the remaining ink amount and an increase in the variation in the remaining ink amount occur. Furthermore, in the case of a foam-type ink tank, since the ink is absorbed and held in the foam, there is a high risk of foreign matter entering the ink supplied from the foam-type ink tank. There is a high risk of causing problems such as head clogging.

In view of such problems, the applicant of the present application has proposed an ink cartridge that has a simple structure and can be made compact, and that has high ink extraction efficiency and high ink filling efficiency. For example, such an ink cartridge is proposed in the following patent document.
Japanese Patent Application No. 2002-238491 (Japanese Patent Laid-Open No. 2004-74599)

  FIG. 7 shows an ink cartridge of the type described in this patent document. As shown in this figure, an ink cartridge 100 includes four ink chambers 102 (1) to 102 (4) whose upper ends are opened in parallel inside a cartridge case 101. A waste ink chamber 110 is formed in an L shape.

  Each of the ink chambers 102 (1) to 102 (4) includes a movable lid 103 (1) to 103 (4) movable up and down along the inner peripheral side surface 102a, and each of the ink chambers 102 (1) to 102 (2). Ink extraction portions 104 (1) to 104 (4) formed on the bottom surface of (4). An ink storage portion 105 is defined by the ink chamber bottom surface 102b, the ink chamber peripheral side surface 102a, and the movable lids 103 (1) to 103 (4), and the movable lids 103 (1) to 103 ( 4) is always urged upward, whereby the ink reservoir 105 is held in a negative pressure state.

  The strength of the ink meniscus formed in the gap between the ink chamber peripheral side surface 102a and each of the movable lids 103 (1) to 103 (4) is determined on the ink jet head side acting on the ink takeout portions 104 (1) to 104 (4). The strength is set so as not to be destroyed by the ink suction force.

  The ink cartridge 100 having this configuration can be used as a multi-color ink cartridge in which different color inks are stored in the independent ink chambers 102 (1) to 102 (4).

  However, in the ink cartridge 100 configured as described above, the ink storage portions 105 of the ink chambers 102 (1) to 102 (4) are formed in the gaps between the movable lids 103 (1) to 103 (4) and the ink chamber peripheral side surface 102a. It is held in the ink reservoir 105 by the ink meniscus. Accordingly, when the ink cartridge 100 is accidentally dropped or when an impact force is applied to the ink cartridge 100, the ink meniscus is broken and the back side of the movable lids 103 (1) to 103 (4), that is, There is a possibility that the ink flows out to the waste ink chamber 110 side.

  When ink flows out to the waste ink chamber 110 side, the ink flowing out from the ink chambers 102 (1) to 102 (4) may be mixed with each other. Since the ink that has flowed out to the back side of the movable lids 103 (1) to 103 (4) returns to the ink storage unit 105 again, there is a risk that the mixed-color ink returns to each ink storage unit 105. Further, since the waste ink chamber 110 is filled with foam or felt ink absorbing material, fine foreign substances contained in the ink absorbing material are mixed into the spilled ink and enter the ink reservoir 105 side. There is also a risk of intrusion.

  In view of the above, an object of the present invention is to propose an ink cartridge capable of preventing foreign matter from entering from a waste ink chamber.

  Another object of the present invention is to propose an ink cartridge capable of preventing foreign matter from a waste ink chamber from being mixed and color mixing of outflowed ink.

  A further object of the present invention is to propose an ink jet printer using such a new ink cartridge as an ink supply source.

In order to solve the above-described problems, the ink cartridge of the present invention includes:
A cartridge case with an air release hole for opening the interior to the atmosphere;
Inside the cartridge case, a plurality of ink chambers formed in an open state at the upper end;
A partition member arranged in a state in which the upper end opening of each ink chamber is sealed, and partitions the inside of the cartridge case into each ink chamber and a common ink trap for storing ink overflowing from each ink chamber When,
An ink absorber capable of absorbing and holding the ink filled in the ink trap;
Each ink chamber forms an ink meniscus in the gap between the ink take-out portion formed on the bottom surface of the ink chamber and the inner peripheral side surface of the ink chamber, and the inner circumference of the ink chamber is changed in accordance with the change in the ink storage amount. A movable member movable along a side surface, an ink storage section defined by the bottom surface, the inner peripheral side surface and the movable member, and the movable member for holding the ink storage section in a negative pressure state. And a biasing member that biases
The ink trap is opened to the atmosphere via the atmosphere opening hole;
The partition member includes a plurality of air communication holes formed at positions away from the inner peripheral side surface in a portion sealing the upper end opening of each ink chamber,
The space between the movable member of each ink chamber and the part of the partition member that seals the upper end opening of the ink chamber communicates with the ink trap through each air communication hole. It is characterized by.

  In the ink cartridge according to the present invention, the upper end opening of the ink chamber is formed at a portion corresponding to the upper end opening away from the circumferential surface of the ink chamber, and the atmosphere communication for opening the ink chamber to the atmosphere through the atmosphere opening hole. It is blocked by a partition member having a hole. That is, the ink chamber is separated from the ink trap. Accordingly, the ink that has flowed out from the outer periphery of the movable member to the back side is unlikely to flow out from the atmosphere communication hole to the ink trap side. Even if it flows out, it is trapped by the ink trap, so that the ink can be prevented from flowing out from the air opening hole of the ink cartridge.

  Further, the upper end opening of each ink chamber is sealed by a partition member. Therefore, it is possible to prevent the ink that has flowed out to the back side of the movable member in each ink chamber from being mixed with each other. Therefore, even when the outflowed ink returns to the ink storage unit again, no adverse effect due to color mixing occurs. Further, foreign matter is not mixed into the ink that has flowed out to the back side of the movable member, and the foreign matter does not enter the ink storage portion.

  Here, the present invention is characterized in that the ink absorber is filled in a state surrounding each air communication hole at a position away from each air communication hole.

  When the ink absorber is in contact with the atmosphere communication hole, the ink that has flowed out to the back side of the movable member is sucked up from the atmosphere communication hole to the ink absorber side, resulting in wasted ink. However, in the present invention, only the ink leaking from the air communication hole to the ink trap side is absorbed by the ink absorber, so that waste of ink can be minimized. In addition, since the periphery of the air communication hole is surrounded by the ink absorber, the ink flowing out from the ink chamber to the ink trap side is absorbed by the ink absorber and does not return to the ink chamber.

  In the present invention, each air communication hole on the ink trap side is formed in an upper end protruding portion protruding from the upper surface of the partition member. In this way, since the ink overflowing from the ink chamber to the upper surface of the partition member via the air communication hole is prevented from returning to the ink chamber, the foreign matter is mixed in with the ink, and the foreign matter enters the ink reservoir. This can prevent the harmful effect.

  In the present invention, when the bottom surface of the ink chamber is defined by the bottom plate portion of the cartridge case, the bottom plate portion includes the ink take-out portion and a waste ink collection portion for collecting waste ink in the ink trap. And the atmosphere opening hole may be formed in the top plate portion of the cartridge case.

  On the other hand, the present invention relates to an ink jet printer and is characterized in that the ink cartridge having the above-described configuration is used as an ink supply source. According to the present invention, it is possible to prevent ink color mixing, contamination of foreign matter into the ink, and entry of bubbles into the ink reservoir in the ink cartridge, so there is no danger of clogging of the ink jet head, and printing with high print quality is always possible. It can be performed.

  In the ink cartridge according to the present invention, the upper end opening of the ink chamber is formed at a position away from the circumferential surface of the ink chamber and corresponding to the upper end opening, and the atmosphere for opening the ink chamber to the atmosphere through the atmosphere opening hole. It is sealed by a partition member having a communication hole. Even if the ink cartridge is dropped or an impact force is applied, even if ink flows out from the ink reservoir to the back side of the movable member, the air communication hole on the upper side of the partition member Therefore, the ink flowing out from the periphery of the movable lid does not leak directly from the atmosphere communication hole to the ink trap side. The outflowed ink once accumulates in the space on the back side of the movable member of the ink chamber partitioned by the partition member, but returns to the ink storage portion of each ink chamber again, and can maintain a predetermined amount of ink taken out.

  Similarly, in the case of a multi-color ink cartridge, the ink that has flowed out from each ink chamber is accumulated in the space on the back side of each ink chamber, so that mixing of the inks of the respective colors can be prevented. Therefore, no problem occurs even if the outflowed ink returns to the ink storage part of each ink chamber again. Even if the ink flows out, it is trapped by the ink trap, so that the ink can be prevented from flowing out from the air opening hole of the ink cartridge.

  On the ink trap side, if the atmosphere communication hole is surrounded by an ink absorber that absorbs ink, the ink that has flowed out of the ink chamber is absorbed by the ink absorber and cannot return to the ink chamber. Is. When the ink absorber is separated from the air communication hole, the ink that has flowed out to the back side of the movable member is not sucked up from the air communication hole to the ink absorber and leaks out from the air communication hole to the ink trap. Only the remaining ink is absorbed by the ink absorber. Therefore, waste of ink can be prevented as much as possible.

  Furthermore, when the atmosphere communication hole of the partition member is formed in the upper end protruding portion that protrudes from the upper surface of the partition member, the ink in the ink chamber overflows from the atmosphere communication hole to the upper surface of the partition member. Is prevented from returning to the ink chamber again, so that it is possible to prevent the adverse effect that foreign matter mixed in the ink enters the ink reservoir.

  On the other hand, in the ink jet printer using the ink cartridge of the present invention as an ink supply source, even when an impact is applied, in the ink chamber of the ink cartridge, foreign matter and bubbles do not enter the ink chamber. In the case of an ink cartridge for printing, ink color mixing does not occur. Therefore, clogging of the ink nozzles does not occur, and printing with excellent print quality can be performed.

  Hereinafter, an embodiment of an inkjet printer including an ink cartridge to which the present invention is applied will be described with reference to the drawings.

(Inkjet printer)
FIG. 1 is a schematic configuration diagram of an ink jet printer according to the present embodiment. The ink jet printer 1 includes a platen 3 that conveys the recording paper 2 in the paper feed direction Y, an ink jet head 4 that has a nozzle surface facing the platen 3, and the ink jet head 4 reciprocating in the printing direction X. A carriage 5 for moving, an ink cartridge mounting portion 7 capable of mounting an ink cartridge 10 for multicolor printing that supplies ink of each color to each ink nozzle of the inkjet head 4, and drive control for controlling driving of each portion Device 8.

  As will be described later, the ink cartridge 10 includes, for example, four independent ink chambers each storing black ink, cyan ink, yellow ink, and magenta ink, and one waste ink chamber that collects waste ink. ing. The ink cartridge mounting portion 7 is provided with ink supply needles 7 (1) to 7 (4) for taking out ink from each ink chamber and an ink collection needle 7 (5) for discharging waste ink. . When the ink cartridge 10 is mounted on the ink cartridge mounting portion 7, an ink supply path for supplying ink of each color from the ink cartridge 10 to the inkjet head 4 is formed.

  Further, the ink jet printer 1 includes a nozzle cap 9 at a position deviated from the platen 3 in the printing direction X. The nozzle cap 9 is connected to the ink collection needle 7 (5) via the ink pump 6. Therefore, when the ink cartridge 10 is mounted on the ink cartridge mounting portion 7, a waste ink recovery path from the nozzle cap 9 to the waste ink chamber in the ink cartridge 10 through the ink recovery needle 7 (5) is formed. When the ink pump 6 is driven in a state where the nozzle face 4a of the inkjet head 4 is covered with the nozzle cap 9, waste ink can be collected from the head side into the waste ink chamber.

(ink cartridge)
2A to 2D are a plan view, a front view, a left side view, and a right side view showing the ink cartridge 10, FIG. 3 is a perspective view thereof, and FIG. 4 is an exploded perspective view thereof. 5A and 5B are a cross-sectional view and an enlarged partial cross-sectional view showing a portion cut along AA in FIG.

  First, the overall configuration of the ink cartridge 10 will be described with reference to these drawings. The ink cartridge 10 includes a horizontally long flat rectangular cylindrical cartridge case 12, four ink chambers 13 (1) to 13 (4) formed by partitioning the inside, and one waste ink chamber. 14. The cartridge case 12 is composed of a case main body 12a and a case cover plate (top portion of the cartridge case) 12b sealing the upper end opening of the case main body 12a. The case cover plate 12b is a thin plate and has a back surface. Is almost flat. In the bottom plate portion 21 of the case main body 12a, ink takeout portions 15 (1) to 15 (4) for taking out ink from the ink chambers 13 (1) to 13 (4), and waste ink to the waste ink chamber 14 are provided. A waste ink recovery unit 16 for recovery is formed.

  Next, each part of the ink cartridge 10 will be described in detail. The case body 12a of the cartridge case 12 includes a bottom plate portion 21 on which the ink take-out portions 15 (1) to 15 (4) and the waste ink collecting portion 16 are formed, and a right angle from an edge on the long side of the bottom plate portion 21. It is comprised from a pair of side plate parts 22 and 23 which have stood up, and a pair of end plate parts 24 and 25 which have stood up perpendicularly from the edge of the short side of the baseplate part 21. FIG. In the present embodiment, the end plate portion 25 has an arc shape and smoothly continues to the front and rear side plate portions 22 and 23.

  Inside the case body 12 a of the cartridge case 12, the upper end is opened by four partition plate portions 26, 27, 28, 29 formed so as to be spanned between the pair of side plate portions 22, 23. Four ink chambers 13 (1) to 13 (4) having a circular cross section are formed. The upper end openings 13a of the ink chambers 13 (1) to 13 (4) are sealed by a partition plate 20 that is a partition member made of a single material such as plastic.

  Here, FIGS. 6A and 6B are perspective views when the partition plate 20 is viewed from the upper surface side and the rear surface side, respectively. As shown in these drawings, on the back surface of the partition plate 20, four circles corresponding to the annular edge surface 13b (see FIG. 4) of the upper end opening 13a of each ink chamber 13 (1) to 13 (4). An annular protrusion 20a is formed. The partition plate 20 is joined to the annular end surface 13b by heat-sealing the projection 20a to the annular edge end surface 13b.

  At the center of each annular projection 20a in the partition plate 20, an air communication hole 20b penetrating the partition plate 20 in the thickness direction is formed. A cylindrical protrusion 20c is formed on the outer peripheral edge of the back surface side of each air communication hole 20b. The opening end of each atmosphere communication hole 20b on the upper surface side of the partition plate is located at the center of the upper end protruding portion 20d protruding from the upper surface of the partition plate 20e.

  2 to 5 again, between the partition plate 20 and the case lid plate 12b, an elongated space ink trap extending in the lateral direction is formed. A space for waste ink is formed between the end plate portion 24 and the partition plate portion 26. In this embodiment, since the ink trap and the waste ink chamber communicate with each other to form a substantially L-shaped space, these are referred to as a waste ink chamber 14.

  The waste ink chamber 14 is filled with an ink absorber 17 such as foam or felt. An air release hole 12d is formed in a portion of the case lid plate 12b lateral to the ink chamber 13 (1), and the waste ink chamber 14 is open to the atmosphere through the air release hole 12d. Here, in the waste ink chamber 14, a space 14 a having a circular cross section where the ink absorber 17 does not exist is formed in a portion where each air communication hole 20 b of the partition plate 20 is located. Thereby, the atmosphere communication hole 20b is separated from the ink absorber 17 by the space 14a.

  Next, the structure of the ink chambers 13 (1) to 13 (4) will be described. These ink chambers 13 (1) to 13 (4) are filled with black ink, cyan ink, magenta ink, and yellow ink, respectively. Since the structures of these ink chambers 13 (1) to 13 (4) are the same, the structure of the ink chamber 13 (2) will be described below, and the other ink chambers 13 (1), 13 (3), In the description of 13 (4), the corresponding parts are denoted by the same reference numerals.

  The ink chamber 13 (2) includes a cylindrical container portion 31 including a bottom plate portion 21, a pair of side plate portions 22 and 23, and a pair of partition plate portions 27 and 28. The upper end opening of this cylindrical container portion 31, that is, the upper end opening 13a of the ink chamber 13 (2) is sealed by the partition plate 20 as described above. A coil spring 34 and a movable lid (movable member) 33 are inserted into the cylindrical container portion 31 from the upper end opening 13a prior to heat-sealing the partition plate 20. The movable lid 33 is biased upward by a coil spring 34 (biasing member). An ink extraction portion 15 (2) is formed at the center of the bottom surface of the cylindrical container portion 31.

  The bottom surface 31 b of the cylindrical container portion 31, the inner peripheral side surface 31 a thereof, and the movable lid 33 define an ink storage portion 35 in which ink is stored. The upper space 38 of the movable lid 33 communicates with the waste ink chamber 14 that is open to the atmosphere via the atmosphere communication hole 20 b formed in the partition plate 20.

  The movable lid 33 can be reciprocated up and down along the inner peripheral side surface 31a of the cylindrical container portion 31, and has a disc-like lid main body portion 33a and a cylinder having a fixed length extending downward from the outer peripheral edge. And a trunk portion 33b. By setting the cylindrical body portion 33b to a predetermined length, the movable lid 33 can be smoothly moved without being accompanied by rattling of the movable lid 33 or galling on the inner peripheral side surface of the cylindrical body portion 33b. . When the ink reservoir 35 is filled with ink, the ink enters the gap 37 between the movable lid 33 and the inner peripheral side surface 31a of the cylindrical container portion 31 to form an ink meniscus. By setting the gap 37 to an appropriate size, the strength of the ink meniscus formed in the gap 37 is made larger than the ink suction force acting on the ink take-out portion 15 (2), so that the ink can be drawn even during ink suction. The meniscus can be prevented from being broken.

  For example, the outer diameter of the cylindrical body 33 b of the movable lid 33 is formed to be smaller by about 0.1 mm than the inner diameter of the inner peripheral side surface 31 a of the cylindrical container portion 31. In this case, when the movable lid 33 is inserted into the cylindrical container portion 31 in a concentric state, a gap 37 having a width of 0.05 mm is formed in an annular shape between them. Further, the length is set to 8 mm so that there is no galling on the inner peripheral side surface of the cylindrical body portion 33b.

  Further, since the ink reservoir 35 is always held in a predetermined negative pressure state by the pushing-up force of the movable lid 33 by the coil spring 34, even in a state where the ink suction force does not act on the ink take-out portion 15 (2). Ink does not leak from the ink reservoir 35 via the ink take-out part 15 (2).

  Further, since the pushing force of the movable lid 33 by the coil spring 34 is set to be smaller than the strength of the ink meniscus and the ink suction force acting on the ink take-out hole 15b, the pushing force of the coil spring 34 reduces the ink meniscus. If ink is sucked from the ink take-out part 15 (2) without breaking and air bubbles entering the ink storage part 35, the movable lid 33 moves to the ink take-out part 15 (2) side according to the ink suction amount. Will do. For example, the pushing force of the coil spring is set to 5 gf to 15 gf from the meniscus strength of the gap 37.

  Here, as described above, the cylindrical protrusion 20c slightly protruding downward is formed on the back surface portion of the partition plate 20 corresponding to the central portion of the upper end opening 13a of each of the ink chambers 13 (1) to 13 (4). Each is formed (see FIG. 6B). Since the central portion of the upper surface of the movable lid 33 is a flat surface, when the movable lid 33 rises, the movable lid 33 comes into contact with the circular protrusion 20c in a substantially line contact state, and the movable lid 33 rises further. Absent.

  Further, as shown in FIG. 5B, the portion of the ink chambers 13 (1) to 13 (4) in the vicinity of the bottom surface 31b of the inner peripheral side surface 31a of the ink storage portion 35 has an inner diameter dimension as it goes downward. The tapered inner peripheral side surface portion 31d is gradually reduced. In addition, the inner diameter dimension of the lower end 31e of the tapered inner peripheral side surface part 31d is the same as the outer diameter dimension of the movable lid 33, and the lower part is an arcuate curved inner peripheral surface part 31f. The lower end of the inner peripheral surface portion 31f is smoothly continuous with the bottom surface 31b. Accordingly, when the movable lid 33 descends and approaches the bottom surface 31b, the gap between the movable lid 33 and the inner peripheral side surface 31a is narrowed, and therefore the strength of the ink meniscus formed there is increased. When the lower end of the movable lid 33 reaches the lower end of the tapered inner peripheral side surface portion 31d, the movable lid 33 is fitted into the inner peripheral side surface portion and is locked.

  Next, the structure of the ink extraction unit 15 (2) of this example will be described. A circular opening 41 is formed at the center of the bottom surface of the cylindrical container portion 31, and a cylindrical frame 42 protruding downward from the bottom plate portion 21 is formed from the outer peripheral edge portion. A disc-shaped rubber packing 43 is attached to the cylindrical frame 42, and a through hole opened in the center functions as the ink extraction hole 15b. The cylindrical frame 44 protrudes upward also from the outer peripheral edge portion of the circular opening 41 on the ink storage portion side, and this central opening portion serves as a communication path 45 that communicates the ink take-out hole 15 b and the ink storage portion 35. A valve 46 capable of sealing the ink take-out hole 15b is disposed in the communication path 45, and this valve 46 is always pressed against the back surface of the rubber packing 43 by a coil spring 47 to block the ink take-out hole 15b. .

  A foreign matter removing filter 49 is attached to the upper end opening of the cylindrical frame 44 protruding into the ink reservoir 35. Accordingly, it is possible to prevent foreign matter mixed in the ink supplied from the ink reservoir 35 to the ink supply needle 7 (2) side from being captured by the filter 49 and entering the ink jet head 4 side.

(Ink supply operation, effects)
The ink supply operation and effects of the ink cartridge 10 of this example configured as described above will be described. As shown in FIG. 5, the movable lid 33 is displaced toward the partition plate 20 in the state where the ink storage portions 35 of the ink chambers 13 (1) to 13 (4) are filled with ink of each color. . That is, the movable lid 33 is located near the upper end position of the cylindrical container portion 31.

  In addition, since an ink meniscus is formed in the gap 37 between the movable lid 33 and the inner peripheral side surface 31 a of the cylindrical container portion 31, the upper space 38 on the back side of the movable lid 33 that communicates with the waste ink chamber 14. The ink reservoir 35 is partitioned by the movable lid 33. Further, since the movable lid 33 is pushed up by the coil spring 34, the ink reservoir 35 is held in a predetermined negative pressure state.

  When the ink suction force from the ink jet head 4 side of the ink jet printer 1 acts on the ink takeout hole 15b, the movable lid 33 moves to the ink takeout hole 15b side against the spring force of the coil spring 34. Is supplied to the ink jet head 4 side from the ink take-out hole 15b.

  Here, since the strength of the ink meniscus formed in the gap 37 between the moving movable lid 33 and the inner peripheral side surface 31a of the cylindrical container portion 31 is greater than the ink suction force, the ink meniscus is destroyed by the ink suction force. There is nothing. Therefore, bubbles do not enter the ink reservoir 35 via the gap 37 from the upper side of the movable lid 33. Further, the ink does not leak from the ink storage portion 35 side to the upper side of the movable lid 33 through the gap 37.

  In the ink end state in each of the ink chambers 13 (1) to 13 (4), each movable lid 33 is lowered to a position where it comes into contact with the bottom surface of the cylindrical container portion 31, and the volume of the ink storage portion 35 is minimized. After the movable lid 33 descends to the vicinity of the bottom surface of the cylindrical container portion 31 and reaches the tapered inner peripheral side surface portion 31d of the cylindrical container portion 31, as described with reference to FIG. As the movable lid 33 is lowered, the gap 37 between the movable lid 33 and the tapered inner peripheral side surface portion 31d gradually decreases. As a result, the strength of the ink meniscus formed in the gap 37 increases as the movable lid 33 is lowered. When the movable lid 33 is lowered, the coil spring 34 is compressed and the push-up force of the movable lid 33 is increased, so that the ink meniscus is easily broken.

  However, as described above, since the ink meniscus strength increases as the movable lid 33 is lowered, the ink meniscus can be reliably prevented from being destroyed. Therefore, even when the ink remaining amount is low, the ink meniscus can be prevented from being broken and bubbles can be prevented from entering the ink reservoir 35.

  When the movable lid 33 reaches the lower end 31e of the tapered inner peripheral side surface portion 31d, the inner diameter dimension of that portion is the same as the outer diameter dimension of the movable lid 33, so the movable lid 33 is fitted and locked here. It becomes a state.

  Here, a case where the ink cartridge 10 having this configuration is accidentally dropped or a case where an impact force is applied to the ink cartridge 10 will be described. In this case, the movable lid 33 may vibrate and the ink meniscus in the gap 37 may be temporarily broken, so that the ink flows out to the back side of the movable lid 33. The space 38 on the back side of the movable lid 33 is an independent space for each ink chamber 13 (1) to 13 (4) by the movable lid 33 and the partition plate 20.

  Therefore, the ink that has flowed out here is not mixed with the ink that has flowed out from other ink chambers. In addition, the air communication hole 20b is formed at a position away from the inner peripheral side surface 31a of the ink chamber, and in the present embodiment, it is disposed at a substantially central portion of each ink chamber. The ink that has flowed out does not leak directly from the atmosphere communication hole 20b to the waste ink chamber 14 side. Therefore, the ink collected in the space on the back side is transmitted through the wall surface of the ink chamber and returns to the ink storage portion of each ink chamber, so that a predetermined amount of ink taken out can be maintained.

  The air communication hole 20b on the upper side of the partition plate 20 is provided at the center of the upper end protruding portion 20d protruding from the upper surface 20e of the partition plate. Therefore, even if ink leaks to the waste ink chamber 14 side. The discharged ink does not enter the ink chambers 13 (1) to 13 (4) from the other air communication holes 20b. Therefore, it is possible to prevent color mixing of the leaked ink.

  In addition, since the air communication hole 20 b on the upper side of the partition plate 20 is surrounded by the ink absorbing material 17 filled in the waste ink chamber 14, the ink that has flowed out to the waste ink chamber 14 side enters the ink absorber 17. It is absorbed and does not enter each ink chamber 13 (1) -13 (4) again.

  As described above, the ink that has flowed out of the ink chambers 13 (1) to 13 (4) does not enter the ink chamber again, so that foreign matter or the like when contacting the ink absorber 17 is mixed into the ink in the ink chamber. There is nothing. Therefore, even if the ink that has flowed out to the back side of the movable lid 33 returns to the ink storage part 35 through the gap 37 between the movable lid 33 and the inner peripheral side surface 31a again, problems such as color mixing and foreign matter contamination occur in the ink. do not do.

  Furthermore, when a large amount of ink flows out and the space 38 is filled with ink, the ink absorber 17 is not in contact with the air communication hole 20 b that communicates the space 38 and the waste ink chamber 14. The ink that has flowed out of the air communication hole 20b is not sucked up by the ink absorber 17. Therefore, since only the ink leaking into the waste ink chamber 14 from the atmosphere communication hole 20b is only absorbed by the ink absorber 17, generation of waste ink can be suppressed as much as possible.

  Furthermore, since the movable lid 33 is in contact with the cylindrical protrusion 20c of the partition plate 20, there is a risk that the upper surface of the movable lid 33 comes into surface contact with the partition plate 20 and sticks to the partition plate 20. Absent.

  In addition to this, when the remaining amount of ink decreases and the movable lid 33 approaches the bottom surface portion, the gap 37 gradually decreases, so that the ink meniscus strength increases. Therefore, even if the push-up force of the coil spring 34 acting on the movable lid 33 is increased, the ink meniscus is broken and air bubbles can be reliably prevented from entering the ink reservoir.

(Other embodiments)
The ink cartridge 10 according to the above embodiment includes four ink chambers, but the present invention can be similarly applied even when a plurality of ink chambers other than four are provided.

  In addition, this embodiment has taken the best measures, but it cannot be achieved unless all the measures are taken. For example, the air communication hole 20b on the upper side of the partition plate 20 is provided in the upper end protruding portion 20d that protrudes from the upper surface 20e of the partition plate. This prevents movement to another ink chamber and prevents color mixing.

  Furthermore, in the present embodiment, the ring-shaped phenomenon in which the contact surfaces of the partition plate 20 and the movable lid 33 are in close contact with each other is eliminated by the cylindrical projection 20c provided on the partition plate 20, but the projection is only the movable lid 33. It may be in both or both.

It is a schematic block diagram which shows the example of the inkjet printer which uses the ink cartridge to which this invention is applied as an ink supply source. (A)-(d) is the top view, front view, left side view, and right side view which respectively show the ink cartridge of FIG. FIG. 2 is a perspective view showing the ink cartridge of FIG. 1. FIG. 2 is an exploded perspective view showing the ink cartridge of FIG. 1. (A) is sectional drawing of the part which cut | disconnected the ink cartridge of FIG. 2 by AA, (b) is the partial expanded sectional view. (A) And (b) is a perspective view at the time of seeing the partition plate in the ink cartridge of FIG. 2 from the upper side and the lower side, respectively. It is explanatory drawing which shows the ink cartridge used as the premise of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inkjet printer, 4 Inkjet head, 7 Ink cartridge mounting part, 7 (1) -7 (4) Ink supply needle, 7 (5) Ink collection needle, 10 Ink cartridge, 12 Cartridge case, 12a Case main body, 12b Case lid Plate, 13 (1) -13 (4) Ink chamber, 14 Waste ink chamber (ink trap), 14a Empty space, 15 (1) -15 (4) Ink take-out part, 16 Waste ink recovery part, 17 Ink absorber , 20 Partition plate, 20a Toroidal projection, 20b Atmospheric communication hole, 20c Cylindrical projection, 20d Top projection, 20e Top surface, 21 Bottom plate portion, 22, 23 Side plate portion, 24, 25 End plate portion, 26-29 Partition plate Portion, 31 cylindrical container portion, 31a inner peripheral side surface, 31b bottom surface, 31d tapered inner peripheral side surface portion, 33 Movable lid, 34 coil spring, 35 ink reservoir, 37 gap, 38 space on the back side of the movable lid

Claims (5)

A cartridge case with an air release hole for opening the interior to the atmosphere;
Inside the cartridge case, a plurality of ink chambers formed in an open state at the upper end;
A partition member arranged in a state in which the upper end opening of each ink chamber is sealed, and partitions the inside of the cartridge case into each ink chamber and a common ink trap for storing ink overflowing from each ink chamber When,
An ink absorber capable of absorbing and holding the ink filled in the ink trap;
Each ink chamber forms an ink meniscus in the gap between the ink take-out portion formed on the bottom surface of the ink chamber and the inner peripheral side surface of the ink chamber, and the inner circumference of the ink chamber is changed in accordance with a change in the ink storage amount. A movable member movable along a side surface; an ink storage section defined by the bottom surface, the inner peripheral side surface and the movable member; and the movable member for holding the ink storage section in a negative pressure state. And a biasing member that biases
The ink trap is opened to the atmosphere through the atmosphere opening hole,
The partition member includes a plurality of air communication holes formed at positions away from the inner peripheral side surface in a portion sealing the upper end opening of each ink chamber,
The space between the movable member of each ink chamber and the portion of the partition member that seals the upper end opening of the ink chamber communicates with the ink trap through each air communication hole. An ink cartridge characterized by.   The ink cartridge according to claim 1, wherein the ink absorber is filled in a state surrounding each air communication hole at a position away from each air communication hole.   3. The ink cartridge according to claim 1, wherein each air communication hole on the ink trap side is formed at an upper end protruding portion protruding from an upper surface of the partition member. The bottom surface of the ink chamber is defined by the bottom plate portion of the cartridge case,
The bottom plate portion is formed with an ink takeout portion for taking out the ink from the ink chamber, and a waste ink collection portion for collecting waste ink in the ink trap,
The ink cartridge according to any one of claims 1 to 3, wherein the air opening hole is formed in a top plate portion of the cartridge case.   An ink jet printer using the ink cartridge according to any one of claims 1 to 4 as an ink supply source.

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