JP2008246827A - Liquid container and ink-jet recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that a convexed sheet is caught between a plate member and a rib and torn due to the dropping and the like in an ink tank which makes a shifting force interact to the convexed sheet through the plate member and makes a negative pressure interact in an ink storage chamber. <P>SOLUTION: The convexed sheet 13 makes the thickness of the portion corresponding to the contact area 60 which is caught between the plate member and the rib at dropping thicker than the thickness of the portion corresponding to a non-contact area 61. The increase of an ink residual amount at the time of using up the ink is prevented by forming a projection 62 in the corners of the convexed sheet 13 to compensate the lack of the perimeter of the convexed sheet 13. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a liquid storage container and an ink jet recording apparatus using the liquid storage container. More specifically, the present invention relates to a liquid storage container that generates a negative pressure in an ink storage chamber by expanding a volume of a bag-shaped ink storage chamber using a biasing member such as a spring. In addition to a general inkjet printer, the present invention is an apparatus such as a copying machine, a facsimile having a communication system, a word processor having a printing unit, and an industrial recording apparatus combined with various processing apparatuses. Can be applied.

  The ink jet recording apparatus includes a recording head that performs recording by discharging ink, and an ink tank that stores ink to be supplied to the recording head. A so-called serial type ink jet recording apparatus includes a carriage on which a recording head is mounted, and performs recording by ejecting ink from the ejection port of the recording head to the recording medium while moving the carriage relative to the recording medium. A so-called full-line type ink jet recording apparatus uses a recording head in which ejection openings are arranged in a range corresponding to the width of the transported recording medium, and ejects ink onto the recording medium transported to the recording head. To record.

  In such an ink tank that stores ink to be supplied to the recording head, the ink is stored at a predetermined negative pressure with respect to the recording head. This negative pressure is a negative pressure for preventing ink leakage from the ejection port in balance with the holding force of the ink meniscus formed in the vicinity of the ejection port of the recording head. The negative pressure is set to an appropriate negative pressure within a predetermined range that enables the ink ejection operation of the recording head.

  As a mechanism for generating a negative pressure, a bag-shaped member is formed by a flexible film, and the flexible film is attached in a direction in which the volume of the bag-shaped member is expanded by a negative pressure generating member provided inside the bag-shaped member. A device that applies a negative pressure to the ink inside the bag-like member is known. As a negative pressure generating member, a plate member is generally joined with a spring.

  The negative pressure in the ink tank is generated by the reaction force of the spring through the plate member. If the position of this plate member shifts, the reaction force of the spring is not constant and the internal pressure becomes unstable. It becomes. Therefore, it is desirable not to move the plate member from a certain position so that a stable negative pressure can be obtained.

As a technique for this purpose, as in Patent Document 1, a rib is provided so as to surround the outer periphery of the plate member, thereby restricting the movement of the plate member, particularly in the direction parallel to the surface of the plate member. There are some which join and a board member and a flexible film like patent documents 2.
JP 2004-122498 A JP-A-6-226993

  However, in the ink tank structure described in Patent Document 1, the flexible film constituting the ink storage chamber is sandwiched between the plate member and the rib due to a drop or vibration during distribution or user use. May cause problems. The cause of this problem is thought to be largely due to the ink tank manufacturing method.

  The ink tank manufacturing method described in Patent Document 1 is a method in which a flat flexible film is first welded to an ink tank housing, and then the film is formed. Specifically, the flexible film is welded to the casing while being flat, and the welded casing itself is used as a mold for the flexible film. And the recessed part of a housing | casing becomes a convex part of a flexible film by heating the welded flexible film and carrying out the suction exclusion of the air in the space between the flexible film and a housing | casing. Mold as follows. Thereby, a flexible film can be shape | molded in the desired shape containing a convex type | mold, without positioning with respect to a welding part. Further, since the transparent thin film flexible film, which has been difficult to handle until now, becomes the same component as the casing, it has the advantage that it is easy to handle. In addition, by forming a flexible film along the inside of the ink tank casing, it is possible to make the ink tank almost free of ink when the ink is used up.

  However, the convex portion of the flexible film formed by the casing has a thickness corresponding to the depth of the concave portion of the casing serving as the convex mold, and the thickness may be insufficient. That is, when forming a convex shape by molding a flexible film, the flexible film cools down when it comes into contact with the inner wall of the concave portion of the housing, and is difficult to stretch. Therefore, the corner portion of the deepest part of the casing where the flexible film comes into contact with the casing lastly extends most. That is, the thinnest portion. According to the configuration of the ink tank of Patent Document 1, the thinnest portion of the flexible film is a portion where the plate member abuts, and is a portion that is sandwiched between the plate member and the rib. It is easy to tear.

  As a countermeasure against the tearing of the flexible film of the ink tank as described above, for example, as in Patent Document 2, a thin film made of resin is sandwiched between the plate member and the flexible film. Some have reduced damage to flexible films. It is also conceivable to attach a cushioning material to the rib, or to change the rib to a flexible material such as rubber. However, in any case, the cost increases greatly.

  Further, as another countermeasure against the breakage of the flexible film, it is conceivable to increase the thickness of the region sandwiched between the plate member and the rib of the flexible film. As the technique, there is a technique of forming a flexible film using a convex mold having a shape in which the internal cross-sectional length of the ink tank is matched. By using this method, it becomes possible to increase the thickness near the plate member where there is a risk of the flexible film breaking without changing the thickness of the flexible film before molding. A sufficient effect can be obtained as a countermeasure. However, the flexible film in the region near the plate member is a region that turns over immediately before the ink is used up. Immediately before the flexible film is used up, the straight part first turns over, and then the corner part where the ridge lines intersect and the rigidity is increased is turned over. If the rigidity of this region is high, the negative pressure suddenly increases and exceeds the allowable value, causing a problem that the amount of ink that cannot be used increases.

  The present invention has been made to solve the above-described conventional problems. The purpose is to prevent tearing of the flexible member due to dropping, etc. without greatly increasing the cost by adding parts, etc., and a liquid storage container that is easy to use and an ink jet using the liquid storage container It is to provide a recording apparatus.

In order to achieve the above object, the liquid storage container of the present invention comprises:
A case member having a supply port for leading out the liquid contained therein;
A flexible member formed into a convex shape having a turn that forms a liquid storage chamber by joining a part of the case member inside the case member;
A spring member for biasing the flexible member in a direction in which the liquid storage chamber expands to generate a negative pressure in the liquid storage chamber;
A plate member disposed between the spring member and the flexible member;
In a liquid storage container comprising: a regulating member that abuts the plate member and the flexible member and regulates movement of the plate member in a direction along the contact surface.
A non-contact region that does not contact with a contact region that contacts the restriction member via the flexible member by the movement of the plate member;
The flexible member is characterized in that the thickness of the portion corresponding to the contact area is thicker than the thickness of the portion corresponding to the non-contact area.

  Further, the flexible member is formed by a convex mold.

In order to achieve the above object, the ink jet recording apparatus of the present invention comprises:
In an inkjet recording apparatus comprising: a recording head that performs recording by discharging ink; and an ink tank that stores ink to be supplied to the recording head.
The liquid container is used as the ink tank.

  According to the above configuration, it is possible to increase the thickness and increase the strength of the flexible member only in the region that is damaged when dropped. Thereby, even if the liquid container receives a strong impact and the plate member comes into contact with the regulating member at a large acceleration, the flexible member is torn by sandwiching the flexible member between the plate member and the regulating member. Can be prevented.

  As a result, it is possible to prevent tearing of the flexible member due to dropping of the liquid storage container during distribution or user use without adding significant cost by adding parts, etc., and provide a liquid storage container that is easy to use can do.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Hereinafter, a case where the liquid storage container of the present invention is applied as an ink tank for storing ink to be supplied to a recording head in an ink jet recording apparatus will be described as an example.

  FIG. 1 is a perspective view showing an outline of the appearance of an ink tank according to an embodiment of the present invention. 2 is an exploded perspective view of the ink tank, and FIG. 3 is a cross-sectional view taken along the line AA of the ink tank shown in FIG. 3A is a cross-sectional view illustrating a state where the ink storage chamber is filled with ink, and FIG. 3B is a cross-sectional view illustrating a state where the ink in the ink storage chamber is used up.

  As shown in FIG. 1, the ink tank 1 of the present embodiment has an exterior configuration that includes a casing 10 that forms a case member of the ink tank 1 and a lid member 14 that also forms the case member. An ink storage chamber that is a liquid storage chamber is provided. Further, the ink tank 1 is provided with a supply port 18 for leading ink to a recording head (not shown) on the bottom surface thereof.

  As shown in FIG. 2, the ink tank 1 includes a casing 10, a spring member 11, a plate member 12, a convex sheet 13 that is a flexible member, a lid member 14, a meniscus forming member 15, and a presser plate 16. ing.

  The material of the housing 10 can be, for example, polypropylene. The supply port 18 includes a meniscus forming member 15, and the meniscus forming member 15 is attached by pressing its outer periphery with a pressing member 16. The meniscus forming member 15 is, for example, a capillary member formed from a polypropylene fiber material and having a capillary force, or the capillary member and a filter member (transmission size is about 15 to 30 μm, and the material is, for example, a stainless steel material or polypropylene). It is a combination. The meniscus forming member 15 and the ink storage chamber inside the housing 10 communicate with each other through an ink flow path (not shown), and a meniscus is formed with ink so that bubbles do not enter the ink storage chamber from the outside. is doing.

  Since the plate member 12 is a material that comes into contact with ink, the plate member 12 is made of a metal material such as stainless steel or a resin that does not contain a material that elutes into the ink. Further, since the plate member 12 is disposed inside the ink tank 1, the material strength necessary for transmitting the pressure of the spring member 11 described later to the flexible convex sheet 13 is ensured, and the ink is preferably used. It is necessary to consider not reducing the capacity. In particular, in the ink tank 1 having a small ink capacity, a metal material is desirable in terms of strength and ink capacity. As shown in FIG. 2, the plate member 12 is formed by rounding the corners as a whole and then folding back the end 12 a as shown in FIG. 3, and the plate member 12 is formed into a thin convex sheet 13. The damage done is reduced.

  The housing 10 which is a case member forms an ink storage chamber by joining the convex sheet 13 to the peripheral edge of the opening which forms a part of the case member by welding. The convex sheet 13 is an extremely soft and deformable flexible film (thickness of about 10 to 100 μm). Before the ink consumption, the convex sheet 13 is folded back along the plate member 12 as shown in FIG. It has a convex shape. Then, the shape is changed from a convex shape to a concave shape in accordance with the consumption of ink, and when the ink is used up, the shape is almost along the inside of the housing 10. The spring member 11 biases the convex sheet 13 via the plate member 12 in the direction in which the ink storage chamber expands, thereby generating a negative pressure in the ink storage chamber. The spring member 11 is made of, for example, a stainless material. A lid member 14 is attached to the opening of the housing 10 to protect the convex sheet 13. The lid member 14 is provided with an atmosphere communication portion 17, and the outside of the ink storage chamber inside the housing 10 is at atmospheric pressure.

  FIG. 4 is a view showing the rib 50 provided on the lid member 14. 4A is a perspective view, and FIGS. 4B and 4C are views of FIG. 4A viewed from the direction of arrow a.

  The rib 50 is in contact with the plate member 12 via the convex sheet 13, and the plate member 12 moves in a direction along the contact surface, that is, perpendicular to the direction in which the plate member 12 moves when ink is consumed. It is a regulating member that regulates movement in the direction. The rib 50 is provided for the purpose of ensuring negative pressure stability when the ink tank 1 is used.

  In this embodiment, as shown in FIG. 4B, the rib 50 corresponding to the corner of the plate member 12 indicated by the broken line portion B has a clearance with the plate member 12 from the portion other than the broken line portion B. Also try to get bigger. As a result, even if the plate member 12 moves due to an impact such as dropping, the corners of the plate member 12 having a large clearance do not reach the rib 50, so that the convex sheet 13 located there is not torn.

  That is, the convex sheet 13 in the portion where the broken line portion C, which is the movable range of the plate member 12, indicated by the arrows D <b> 1 to D <b> 4 in FIG. Since it may be pinched, it is an area where the thickness of the convex sheet 13 must be increased.

  FIG. 5 is a diagram for explaining the movement of the plate member 12 and the convex sheet 13 when the ink tank 1 receives a strong impact such as dropping.

  FIG. 5A shows the state of the ink tank 1 before receiving a strong impact such as dropping. In a normal use state, the convex sheet 13 is deformed to the inner side by the negative pressure in the liquid storage chamber for storing ink, and the plate member 12 is held substantially vertically.

  FIGS. 5B and 5C show a state immediately after the ink tank 1 receives a strong impact such as dropping. After the ink tank 1 falls and reaches the ground, the plate member 12 and the ink 19 start moving due to their inertial force. As the ink 19 moves, the convex sheet 13 starts to deform following the movement. The plate member 12 also moves at the same speed and moves until it abuts against the rib 50 provided on the lid member 14 via the convex sheet 13.

  FIG. 5B shows a case where the plate member 12 reaches the rib 50 while the convex sheet 13 follows the plate member 12. In this case, the portion of the convex sheet 13 indicated by the point (1) is damaged. Further, as shown in FIG. 5C, the ink 19 enters between the plate member 12 and the convex sheet 13, and the plate member 12 reaches the rib 50 in a state where the plate member 12 and the convex sheet 13 are separated. There is also a case. In this case, since the convex sheet 13 is pressed against the lid member 14 by the ink 19, the portion of the convex sheet 13 indicated by the point (2) at a position different from the case of FIG. 5B is damaged.

  As described above, the behavior of the plate member 12 and the convex sheet 13 due to the impact at the time of dropping is not constant, and a portion where the convex sheet 13 is damaged is slightly displaced. A region for increasing the thickness of 13 must be set. In addition, the behavior of the plate member 12 and the convex sheet 13 due to the impact at the time of dropping differs depending on the configuration of the ink tank 1, so when the configuration of the ink tank 1 is changed, a drop test is actually performed each time the convexity is detected. It is necessary to grasp the area where the mold sheet 13 is damaged.

  FIG. 6 is an enlarged view of a portion E in FIG. In the present embodiment, as shown in FIG. 6, the damaged portion of the convex sheet 13 due to impact such as dropping is set as an “arrow F” including the above points (1) and (2), and the convex sheet 13 Is set as a region to increase the thickness of the.

  FIG. 7 is a view showing the convex sheet 13. FIG. 7A is a perspective view, and FIG. 7B is a view of FIG. 7A viewed from the direction of the arrow b.

  The convex sheet 13 has a shape as shown in FIG. 7A, and has a contact area 60, a non-contact area 61, and a protrusion 62 as shown in FIG. 7B. Yes.

  The contact region 60 corresponds to a region in which the convex sheet 13 may be sandwiched between the plate member 12 and the rib 50 due to the impact such as the drop described above (arrows D1 to D4 in FIG. 4C), and , Arrow F) in FIG.

  If the convex sheet 13 in the contact area 60 does not have a thickness that can withstand an impact such as dropping, the convex sheet 13 is torn and causes ink leakage. In the configuration of the ink tank 1 of the present embodiment, the thickness of the contact region 60 is determined to be 56 μm or more using the result of an actual drop test. However, the thickness that can withstand an impact such as a drop varies depending on the configuration of the ink tank 1, such as the material of the convex sheet 13 and the shape and material of the plate member 12.

  The non-contact area 61 is an area where the convex sheet 13 is not sandwiched between the plate member 12 and the rib 50 due to an impact such as dropping, and refers to an area other than the contact area 60.

  The thickness of the convex sheet 13 in the non-contact area 61 may be thinner than the thickness of the contact area 60. In the present embodiment, the thickness is about 15 to 50 μm. Any thickness that does not break when the is in operation.

  Next, the convex part 62 provided in the non-contact area | region 61 of the corner | angular part of the convex sheet | seat 13 is demonstrated, comparing with the convex sheet | seat 80 which does not provide the convex part 62 as a comparative example.

  FIG. 8A is a perspective view of a convex sheet 80 as a comparative example, and the convex sheet 80 is not provided with convex portions 62 at the corners. FIG. 8B is a diagram showing a state where the ink tank is used up in the ink tank using the convex sheet 80 which is not provided with the convex portion 62 as a comparative example, and is a cross-sectional view taken along line AA in FIG.

  In the ink tank using the convex sheet 80, as shown in FIG. 8B, a large gap is formed between the housing 10 and the convex sheet 80 when the ink is used up, and the remaining ink increases. End up. As shown in FIG. 8C, which is a cross-sectional view taken along the line II of FIG. 8B, the peripheral length L1 of the convex sheet 80 having the same cross section as the peripheral length L0 inside the housing 10 This gap is caused by a large difference. According to FIG.8 (c), it turns out that the perimeter corresponding to H1 and H2 is insufficient in each corner | angular part.

  On the other hand, in the ink use-up state of the ink tank 1 using the convex sheet 13 having the convex portion 62 of the present embodiment, the convex sheet 13 substantially extends along the housing 10 as shown in FIG. It is in a state and the gap is small. As shown in FIG. 9B, which is a KK cross-sectional view of FIG. 9A, this is the effect of the steps G <b> 1 to G <b> 8 caused by providing the convex portions 62 at the corners of the convex sheet 13. It is. The shortage lengths H1 to H8 in the convex sheet 80 of the comparative example in which the convex part 62 is not provided are compensated by the steps G1 to G8 of the convex part 62, and the peripheral length L2 of the convex sheet 13 and the peripheral length of the housing 10 are compensated. The relationship of L0 is “L0 = L2”. This prevents an increase in the remaining ink amount when the ink is used up.

  Next, a method for forming the convex sheet 13 will be described with reference to FIGS. 10 and 11.

  The convex sheet 13 is formed by the molding method shown in FIGS.

  First, as shown in FIG. 10A, a sheet heating device (for example, a flat sheet 13 ′ fixed by a fixing jig 30 is contacted with a convex mold 20 for forming the flat sheet 13 ′ into a convex mold. The sheet 13 'is softened in advance by a far-infrared heater 31). At that time, the convex mold 20 is waiting on the sheet 13 '.

  Next, as shown in FIG. 10 (b), the convex mold 20 is lowered, and the convex portion 21 and the outer peripheral portion 25 of the convex mold 20 come into contact with the heated sheet 13 ', whereby the sheet 13 A closed space is formed by 'and the inside of the convex mold 20.

  Thereafter, as shown in FIG. 10C, a closed space between the sheet 13 and the convex mold 20 is formed from the opening 22 of the convex mold 20 using a vacuum suction device communicating with the suction pump. Exclude the air present. Thereby, the heated sheet 13 ′ is formed into the shape of the convex sheet 13 according to the shape of the convex mold 20.

  The convex sheet 13 formed by the above method is formed thick in the order in which the heated sheet 13 ′ comes into contact with the convex mold 20. Therefore, in the present embodiment, the contact region 60 that is the portion where the convex sheet 13 is to be thickened most is configured to be the tip of the convex mold 20.

  FIG. 11 is a view showing a convex mold 20 used for forming the convex sheet 13. 11A is a perspective view, FIG. 11B is a CC cross-sectional view of FIG. 11A, and FIG. 11C is a DD cross-sectional view of FIG. 11A.

  As shown in FIG. 11A, a flat portion 21 a is provided at the tip of the convex portion 21 of the convex mold 20 according to the contact area 60 of the convex sheet 13. Since the width of the contact region 60 is F, the width of the flat portion 21a may be F as shown in FIG.

  Moreover, the recessed part 21b for forming the convex part 62 of the convex sheet | seat 13 is provided in the corner | angular part of the plane part 21a. As shown in FIG. 11C, the tip of the concave portion 21b is configured not to have the flat surface portion 21a. As a result, the thick region of the sheet, such as the flat surface portion 21a, is not formed at the tip of the concave portion 21b. That is, the convex portion 62 of the convex sheet 13 is formed thinner than the contact region 60.

  Thus, by reducing the thickness of the convex part 62 of the convex sheet 13, the rigidity of the convex sheet 13 at the corners is reduced, and the ink consumption is reduced due to a sudden increase in negative pressure immediately before the ink is used up. Can be prevented.

  According to the above configuration, it is possible to increase the strength by increasing the thickness of the convex sheet 13 only in the region that is damaged when dropped. Thereby, even if the ink tank 1 receives a strong impact and the plate member 12 contacts the rib 50 with a large acceleration, the plate member 12 sandwiches the convex sheet 13 between the ribs 50 and the convex sheet 13 is torn. Can be prevented. Furthermore, it is possible to control the thickness and cross-sectional length of the convex sheet 13 in the vicinity of the plate member 12, which has a detrimental effect on the ink useability, and it is possible to provide the ink tank 1 with good useability.

1 is a perspective view illustrating an outline of an appearance of an ink tank according to an embodiment of the present invention. It is a disassembled perspective view of the ink tank shown in FIG. 2A is a cross-sectional view of the ink tank shown in FIG. 1, wherein FIG. 1A is a cross-sectional view illustrating a state where the ink storage chamber is filled with ink, and FIG. 2B is a cross-section illustrating a state where the ink in the ink storage chamber is used up. FIG. It is a figure which shows the rib provided in the cover member used for the ink tank shown in FIG. 1, (a) is a perspective view, (b) and (c) are the figures which looked at (a) from the arrow a direction. . 2A and 2B are diagrams for explaining how the plate member and the convex sheet move when the ink tank shown in FIG. 1 receives a strong impact such as a drop, and FIG. ) And (c) are views showing a state immediately after receiving an impact. It is a figure explaining the damage part of a convex sheet when the ink tank shown in FIG. 1 receives strong impacts, such as dropping. It is a figure which shows the convex sheet | seat used for the ink tank shown in FIG. 1, (a) is a perspective view, (b) is the figure which looked at (a) from the arrow b direction. It is a figure which shows the convex sheet | seat which concerns on a comparative example, (a) is a perspective view, (b) is sectional drawing explaining an ink use-out state, (c) is II sectional drawing of (b). It is a figure explaining the ink use-up state of the convex sheet | seat shown in FIG. 7, (a) is sectional drawing, (b) is KK sectional drawing of (a). 8A and 8B are diagrams illustrating a method for forming the convex sheet shown in FIG. 7, in which FIG. 7A is a diagram illustrating a sheet heating process, FIG. 7B is a diagram illustrating a convex mold contact process, and FIG. It is a figure explaining a suction process. It is a figure which shows the convex metal mold | die used for shaping | molding of the convex sheet | seat shown in FIG. 7, (a) is a perspective view, (b) is CC sectional drawing of (a), (c) is (a). It is DD sectional drawing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ink tank 10 Case 11 Spring member 12 Plate member 13 Convex type sheet 13 'Sheet (before molding)
14 Lid member 15 Meniscus forming member 16 Holding plate 17 Atmospheric communication port 18 Supply port 19 Ink 20 Convex mold 21 Convex part 21a Flat part 21b Concave part 22 Opening part 25 Peripheral part 30 Fixing jig 31 Sheet heating device 50 Rib 60 Contact area 61 Non-contact area 62 Projection

Claims (3)

A case member having a supply port for leading out the liquid contained therein;
A flexible member molded into a convex shape, having a turn, which forms a liquid storage chamber by joining a part of the case member inside the case member;
A spring member for biasing the flexible member in a direction in which the liquid storage chamber expands to generate a negative pressure in the liquid storage chamber;
A plate member disposed between the spring member and the flexible member;
In a liquid storage container comprising: a regulating member that abuts the plate member and the flexible member and regulates movement of the plate member in a direction along the contact surface.
A contact region where the plate member contacts the regulating member via the flexible member by movement and a non-contact region where the plate member does not contact;
The flexible container is characterized in that the portion of the flexible member corresponding to the contact area is thicker than the thickness of the part corresponding to the non-contact area.   The liquid container according to claim 1, wherein the flexible member is formed by a convex mold. In an inkjet recording apparatus comprising: a recording head that performs recording by discharging ink; and an ink tank that stores ink to be supplied to the recording head.
An ink jet recording apparatus using the liquid container according to claim 1 or 2 as the ink tank.

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