Patent Publication Number: US-2023150267-A1

Title: Liquid container and method of manufacturing the same

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application is a continuation of U.S. patent application Ser. No. 17/171,904, filed on Feb. 9, 2021, which claims priority from Japanese Patent Application No. 2020-026485, filed Feb. 19, 2020, and Japanese Patent Application No. 2020-196187, filed Nov. 26, 2020, which are hereby incorporated by reference herein in their entireties. 
    
    
     BACKGROUND 
     Field of the Disclosure 
     The present disclosure relates to a liquid container and also to a method of manufacturing such a liquid container. 
     Description of the Related Art 
     Liquid containers to be mounted in liquid ejection apparatus so as to contain liquid to be ejected from the liquid ejection apparatus have been and are being popularly in use. Japanese Patent Application Laid-Open No. 2019-107823 discloses a liquid container comprising a liquid container bag for containing liquid, a pair of tubes arranged in the inner space of the liquid container bag, each having a first end and a second end, and a connection member fitted to the aperture of the liquid container bag. The first end of each of the pair of tubes is open to the inner space of the liquid container bag and the second end thereof is connected to the connection member. The liquid container further comprises a tube holding member also arranged in the inner space of the liquid container bag. The first ends of the pair of tubes are fastened to the respective corresponding nozzles formed at the holding member. 
     The holding member described in Japanese Patent Application Laid-Open No. 2019-107823 is formed by using two component members. The reason why is presumably to avoid interference between the mold to be used for molding the holding member and the nozzles. If so, the two component members of the holding member need to be molded by means of two separate molds and, after molding the two component members, the two component members need to be put together which may entail high manufacturing cost. 
     SUMMARY 
     An aspect of the present disclosure is to provide a liquid container whose holding member can integrally be molded as a single molded product by modifying the structure of holding member of the liquid container at the tube fastening positions thereof to consequently improve the ink feeding performance of the liquid container. Another aspect is to provide a method of manufacturing a holding member to be used in such a liquid container by way of integral molding. 
     The present disclosure generally relates to a liquid container to be mounted in a liquid ejection apparatus so as to contain liquid to be ejected from the liquid ejection apparatus and also to a method of manufacturing a holding member to be used in such a liquid container. A liquid container according to the present disclosure includes a cassette, a liquid container bag mounted in the cassette so as to contain liquid to be ejected from a liquid ejection apparatus, and a connection member arranged at an opening part of the liquid container bag, with the opening part being located at an end of the liquid container bag. The liquid container further includes a holding member including a linker portion having opposite ends of which one end is connected to the connection member and the other end is located in an inside of the liquid container bag so as to extend into the inside of the liquid container bag, and a spacer portion connected to the other end of the linker portion. Additionally, the liquid container includes a tube, of which one end is fitted to the spacer portion and the other end is fitted to the connection member so as to draw out liquid from the liquid container bag, with the spacer portion having a main groove for receiving the one end of the tube to be fitted thereinto and an auxiliary groove communicating with the main groove such that a non-contact space is formed partially in the main groove as arranged between an inner lateral surface of the main groove and an outer lateral surface of the tube fitted into the main groove and the auxiliary grove is held in communication with the non-contact space. 
     A method of manufacturing a holding member to be used in a liquid container employs a first mold having a wall part for forming a main groove for receiving the one end of the tube to be fitted thereinto on one of opposite lateral surfaces of the spacer portion of the holding member, an auxiliary groove held in communication with the main groove and one of opposite lateral surfaces of the connection member, and a second mold having a wall part for forming another main groove for receiving one end of the tube to be fitted thereinto on the other of the opposite lateral surfaces of the spacer portion of the holding member, another auxiliary groove held in communication with the other main groove and the other of the opposite lateral surfaces of the connection member. Each of the wall parts has a portion for forming the main groove with a combination of lateral surfaces forming a right angle or an obtuse angle in cross section perpendicular relative to the extending direction of the main groove. 
     Further features of the present disclosure will become apparent from the following description of exemplary embodiments with reference to the attached drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a schematic perspective view of a liquid ejection apparatus in which a liquid container according to the present disclosure is mounted. 
         FIG.  2 A  is a schematic perspective view of an embodiment of liquid container according to the present disclosure and  FIG.  2 B  is an exploded schematic perspective view of the liquid container shown in  FIG.  2 A . 
         FIG.  3 A  is a schematic lateral cross-sectional view of the liquid container shown in  FIG.  2 A  and  FIG.  3 B  is an exploded schematic perspective view of the holding member and the connection member of the liquid container shown in  FIG.  3 A , while  FIG.  3 C  is an enlarged schematic view of the  3 C region shown in  FIG.  3 A  and surrounded by a circle there. 
         FIG.  4 A  is a schematic top view of the liquid container shown in  FIG.  2 A , showing the holding member and the connection member thereof and  FIG.  4 B  is an exploded schematic view of the holding member and the connection member shown in  FIG.  4 A , while  FIG.  4 C  is an enlarged schematic view of the  4 C region shown in  FIG.  4 A  and surrounded by a circle. 
         FIG.  5 A  is a schematic cross-sectional view of the holding member shown in  FIG.  3 C  and taken along line D-D and  FIG.  5 B  is a schematic cross-sectional view of the exemplar arrangement of the holding member shown in  FIG.  4 A  and taken along line B-B, while  FIG.  5 C  is a schematic cross-sectional view of the exemplar arrangement of the holding member shown in  FIG.  4 A  and taken along line C-C and  FIG.  5 D  is a schematic cross-sectional view of an alternative exemplar arrangement of the holding member. 
         FIG.  6    is a schematic cross-sectional view of the holding member shown in  FIG.  3 C  and taken along line E-E. 
         FIGS.  7 A,  7 B and  7 C  are schematic cross-sectional views of three alternative arrangements of the holding member to which the present disclosure is applicable. 
         FIGS.  8 A,  8 B and  8 C  are schematic lateral cross-sectional views of the liquid container of the comparative example, illustrating a method of manufacturing the holding member. 
         FIG.  9    is a schematic lateral view of the holding member shown in  FIG.  3 B , illustrating the method of manufacturing the same according to the present disclosure. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     Now, an embodiment of the present disclosure will be described below by referring to the drawings. In the following description, the liquid ejection apparatus will be an inkjet printer and the liquid employed for the liquid ejection apparatus will be ink, although the present disclosure is by no means limited to the specifics described for the example embodiment. The direction indicted by arrow X (X-direction) is the direction in which a liquid container  1  is driven to move forward toward a liquid ejection apparatus  100  when the liquid container  1  is to be mounted in the liquid ejection apparatus  10  and backward and away from the liquid ejection apparatus  100  when the liquid container  1  is to be removed from the liquid ejection apparatus  100 . The direction indicated by arrow Y (Y-direction) is the width direction of the liquid container  1  and the direction indicated by arrow Z (Z-direction) is the thickness direction of the liquid container  1 . The X-direction, the Y-direction and the Z-direction are orthogonal relative to one another. The state in which the liquid container  1  is mounted in the liquid ejection apparatus  100  is referred to as “mounted state”. Since the liquid container  1  is mounted in the liquid ejection apparatus  100  in the thickness direction of the liquid container  1  that agrees with the vertical direction, the Z-direction agrees with the vertical direction in the mounted state. 
       FIG.  1    is a schematic perspective view of the liquid ejection apparatus  100  in which an embodiment of liquid container according to the present disclosure has already been mounted in the liquid ejection apparatus  100 . The liquid ejection apparatus  100  has a recording medium containing section (not shown), a recording medium conveyance mechanism (not shown) and other components. The liquid container  1  is contained in a cassette  2  and mounted in the liquid ejection apparatus  100 . The liquid container  1  contains ink that is to be ejected from the recording head of the liquid ejection apparatus  100 . With regard to this embodiment of the present disclosure, a total of four liquid containers  1  respectively containing cyan (C) ink, magenta (M) ink, yellow (Y) ink and black (K) ink are mounted in the liquid ejection apparatus  100 . While all the liquid containers  1  have the same size in  FIG.  1   , the container containing black ink, for instance, may be made bigger than all the remaining liquid containers  1 . The cassette  2  that contains the liquid containers  1  is driven to move forward toward the liquid ejection apparatus  100  so as to be mounted in the liquid ejection apparatus  100  and backward and away from the liquid ejection apparatus  100  so as to be removed from the liquid ejection apparatus  100 . 
       FIG.  2 A  is a schematic perspective view of the liquid container according  1  and  FIG.  2 B  is an exploded schematic perspective view of the liquid container  1 , illustrating the sequence of assembling the liquid container  1 .  FIG.  3 A  is a schematic lateral cross-sectional view of the liquid container  1  and  FIG.  3 B  is an exploded schematic lateral view of the liquid container  1 , illustrating the sequence of assembling the internal structure of the liquid container  1 , while  FIG.  3 C  is an enlarged schematic view of the encircled  3 C region shown in  FIG.  3 A .  FIG.  4 A  is a schematic top view of the liquid container  1  and  FIG.  4 B  is an exploded schematic top view of the liquid container  1 , illustrating how tubes are fitted to the liquid container  1 , while  FIG.  4 C  is an enlarged schematic top view of the encircled  4 C region shown in  FIG.  4 A . 
     As will be described hereinafter, the holding member  4  is formed to include a linker portion  7  and a spacer portion  6 . However, both the linker portion  7  and the spacer portion  6  are omitted from  FIG.  2 A  and  FIG.  2 B  and only the entire holding member  4  is shown there. The tube or tubes  5  for drawing out ink are also omitted from  FIG.  2 A  and  FIG.  2 B . 
     As shown in  FIGS.  2 A and  2 B , the liquid container  1  includes a liquid container bag  3  for containing ink in it. The liquid container bag is preferably made of a flexible material. A tube or tubes (not shown) for drawing out ink from the inside of the bag toward the recording head and a holding member  4  are arranged in the inner space of the liquid container bag  3 . The number of tubes is not specifically defined. In other words, it is sufficient to say that at least a tube is arranged, while a pair of tubes are arranged as shown in  FIGS.  3 A through  3 C  in this embodiment. One of the tubes is referred to as the first tube  5 A and the other tube is referred to as the second tube  5 B hereinafter. The first tube  5 A and the second tube  5 B operate as so many ink flow paths for allowing ink to flow through them. Both the first tube  5 A and the second tube  5 B are formed by using an elastic material such as elastomer. Each of the first tube  5 A and the second tube  5 B has a first end  51  and a second end  52  and extends substantially in the X-direction between the spacer portion  6 A and the connection member  8 , which will be described in greater detail hereinafter. The first ends  51  of both the first tube  5 A and the second tube  5 B are respectively placed in and fitted into the corresponding grooves formed in the spacer portion  6  as will be described in greater detail hereinafter. Additionally, the first ends  51  of both the first tube  5 A and the second tube  5 B are open to the inner space  31  of the liquid container bag  3 . The second ends  52  of both the first tube  5 A and the second tube  5 B are, on the other hand, connected to the connection member  8 . Note that, when viewed in the Z-direction, the openings of the first ends  51  are substantially located in the central part of the liquid container bag  3 . Additionally, in the mounted state, the first end  51  of the first tube  5 A is located in an upper part of the inner space  31 , whereas the first end  51  of the second tube  5 B is located in a lower part of the inner space  31 . The ink to be used in this embodiment contains one or more precipitation components (such as a pigment) and, as time goes by, the concentration of the precipitation component(s) will fall in an upper part of the liquid container bag  3  and rise in a lower part of the liquid container  3 . Thus, consequently, when ink is supplied (drawn out) from the liquid container bag  3 , low concentration ink is supplied (drawn out) from the first tube  5 A and, at the same time, high concentration ink is supplied (drawn out) by way of the second tube  5 B. Then, the low concentration ink drawn out by way of the first tube  5 A and the high concentration ink drawn out by way of the second tube  5 B are mixed and the two different concentrations are averaged to minimize the change with time of the recording quality that the liquid ejection apparatus  100  provides. 
     As seen from  FIGS.  3 A through  3 C , the holding member  4  has a spacer portion  6  that is interposed between the top surface  32  and the bottom surface  33  of the liquid container bag  3  in the mounted state of the liquid container  1  and a linker portion  7  that is connected to the spacer portion  6  and extends in the direction in which both the first and second tubes  5 A and  5 B extend (the X-direction) in the mounted state of the liquid container  1 . The holding member  4  is made of a synthetic resin material such as polyethylene or polypropylene and integrally molded by means of a mold as will be described in greater detail hereinafter. 
     As shown in  FIGS.  3 A through  3 C  and  FIGS.  4 A through  4 C , the spacer portion  6  is substantially symmetrical relative to the center line thereof extending in the X-direction both in terms of X-Z plane and in terms of X-Y plane. As seen from  FIG.  3 C , the spacer portion  6  shows a pentagonal profile and includes a triangular front section  61  and a rectangular rear section  62  as viewed in the Y-direction. On the other hand, as seen from  FIG.  4 C , the spacer portion  6  shows a substantially rectangular profile as viewed in the Z-direction. Furthermore, as shown in  FIG.  3 C , the height (the size in the Z-direction) of the front section  61  rises toward the rear section  62 , whereas the height (the size in the Z-direction) of the rear section  62  substantially remains constant. Additionally, as shown in  FIG.  5 A , the front section  61  has a tapered profile and the width (the size in the Y-direction) of the front section  61  becomes narrower as a function of the distance from the center of the front section  61  as viewed in the Z-direction. Differently stated, as shown in  FIG.  3 C , the front section  61  has downhill slopes in the X-direction and the height of the front section  61  falls as a function of the distance from the rear section  62 , while, as shown in  FIG.  5 A , the front section  61  also has downhill slopes in the Y-direction and the height of the front section  61  falls as a function of the distance from the X-direction center line. As shown in  FIG.  3 C , the height of the rear section  62  is greatest in the holding member  4  and the bottom  64  of the rear section  62  is held in contact with the lower surface  33  of the liquid container bag  3  in the mounted state of the liquid container  1 . The top  63  of the rear section  61  may not necessarily be held in contact with the upper surface  32  of the liquid container bag  3  depending of the amount of ink left in the liquid container bag  3 . However, as the ink in the liquid container bag  3  is consumed and the liquid container bag  3  contracts, the top  63  of the rear section  62  eventually comes into contact with the upper surface  32  of the liquid container bag  3 . The spacer portion  6  secures a constant height in the central part of the liquid container bag  3  regardless of the amount of ink left in the liquid container bag  3 . In other words, the rear section  62  secures a given space in the central part of the liquid container bag  3 . As the ink in the liquid container bag  3  is consumed, the upper surface  32  and the lower surface  33  of the liquid container bag  3  come close to each other as indicated by broken line S in  FIG.  3 A  and ultimately the upper surface  32  comes into tight contact with the lower surface  33  so that ink can no longer be drawn out from the liquid container bag  3 . As will be described in greater detail hereinafter, the first ends  51  of the first and second tubes  5 A and  5 B are fitted into and supported by the spacer portion  6  so that a space is secured by the spacer portion  6  around each of the first ends  51  and hence ink is drawn out from the liquid container bag  3  to the last drop. As described above, the spacer portion  6  operates to prevent the first ends  51  from being closed if the amount of ink left in the liquid container bag  3  becomes very small and allows the ink in the liquid container bag  3  to be drawn out to the last drop to maximize the efficiency of ink utilization. 
     As shown in  FIG.  3 C , the spacer portion  6  has a plurality of walls  65  that extend vertically (in the Z-direction) in parallel with each other as viewed in the X-direction and separated from each other also in the X-direction. A groove  66 A (see  FIG.  4 C ) and grooves  66 B that are held in communication with the inner space  31  of the liquid container bag  3  are formed among the plurality of upwardly extending walls  65 . In other words, as shown in  FIG.  4 C , the grooves include a main groove  66 A (to be referred to as the first main groove hereinafter) that runs through the spacer portion  6  and extends in the X-direction and a plurality of auxiliary grooves  66 B (to be referred to as the first auxiliary grooves hereinafter) that runs orthogonally relative to the first main groove  66 A and extends in the Y-direction. The first auxiliary grooves  66 B are arranged on the opposite sides of the first main groove  66 A as viewed in the Y-direction. The spacer portion  6  shown in  FIG.  4 C  also has grooves arranged among a plurality of walls  65  extending downwardly and oppositely relative to the upward direction (at the rear surface side) as shown in  FIG.  5 A . The spacer portion  6  also has a main groove  67 A (to be referred to as the second main groove hereinafter) that is broader than the first main groove as indicated by broken lines on the rear side of the first main groove  66 A as shown in  FIG.  4 C  and a plurality of auxiliary grooves  67 B (to be referred to as the second auxiliary grooves hereinafter) that run orthogonally relative to the second main groove  67 A and extend in the Y-direction. The second auxiliary grooves  67 B are arranged on the opposite sides of the second main groove  67 A as viewed in the Y-direction. Note that, in  FIG.  4 C , the reference symbols  67 A and  67 B are put in the respective sets of parentheses and shown respectively after the reference symbols  66 A and  66 B in order to tell that the second main groove  67 A and the second auxiliary grooves  67 B are arranged at the respective positions located on the hind sides of the first main groove  66 A and the first auxiliary grooves  66 B. Even when the amount of ink in the liquid container bag  3  is decreased to bring the upper surface  32  of the liquid container bag  3  into tight contact with the spacer portion  6 , ink flows into the inside of the spacer portion  6  from the first main groove  66 A and the first auxiliary grooves  66 B. Additionally, even when the lower surface  33  of the liquid container bag  3  is brought into tight contact with the spacer portion  6 , ink effectively flows into the inside of the spacer portion  6  from the second main groove  67 A and the second auxiliary grooves  67 B. In short, the first main groove  66 A, the first auxiliary grooves  66 B, the second main groove  67 A and the second auxiliary grooves  67 B operate to effectively raise the efficiency of ink utilization. 
     The configuration of the spacer portion  6  will be described below in greater detail by referring to  FIG.  6    (a cross-sectional view taken along line E-E in  FIG.  3 C ). For the purpose of simplification of explanation, the configuration of the spacer portion  6  will be described only by way of the first main groove  66 A, the first auxiliary grooves  66 B and the tube  5 A located on the upper side of the spacer portion  6 . Of the main groove  66 A, the angles (to be referred to as angle parts  6 C for the sake of convenience) formed by the surfaces that operate as the lateral walls of the groove and the surface that operates as the bottom surface are substantially right angles. As the first main groove is made to have angle parts  6 C, the tube (on an assumption that the tube is generally cylindrical in shape) fitted to the groove produces a space part  66 C because the groove is not held in contact with any angle parts  6 C. For instance, ink flows from the first auxiliary grooves  66 B into the space part  66 C that is formed at the angle parts  6 C of the main groove  66 A and then can flow through the space part  66 C and move to the first end  51  of the tube  5 A to consequently extremely minimize the amount of ink left among the first auxiliary grooves  66 B and effectively raise the efficiency of ink utilization. However, when the angle parts  6 C do not show any right angle but show a curved surface of a curvature similar to the curvature of the tube  5 A, no space part  66 C is produced in the region where the angle parts  6 C are formed. Then, the ink that flows from the first auxiliary grooves  66 B to the first main groove  66 A is blocked by the tube  5 A. Then, as a result, the ink can no longer move further on and the amount of ink remaining among the first auxiliary grooves  66 B increases to in turn decrease the efficiency of ink utilization. 
       FIGS.  7 A through  7 C  schematically illustrate alternative configurations of the main groove  66 A that includes angle parts  6 C.  FIG.  7 A  shows an arrangement where a protrusion is formed on the lateral surface that operates as the bottom surface of the main groove  66 A.  FIG.  7 B  shows an arrangement where a recess is formed on the surface that operates as the button surface of the main grooves  66 A. With either of the arrangements that are described above, the disadvantage of the situation where the tube is deformed along the main groove  66 A because of the flexibility of the tube to practically eliminate the space part  66 C can be reduced. In other words, the space part  66 C is secured to allow ink to flow into the angle parts  6 C. When the tube is practically free from any deformation, the angle parts  6 C may be made to show an obtuse angle as shown in  FIG.  7 C  and the bottom surface of the groove may be allowed to show a polygonal profile. Note that it is needless to say that the angle parts  6 C may be made to show a sharp angle. However, from the viewpoint of making the method of manufacturing the holding member  4  a simple one as will be described hereinafter, the use of angle parts  6 C that show a right angle or an obtuse angle is preferable because the use of such angle parts  6 C allows to facilitate the release of the mold from the molded holding member. 
     As shown in  FIGS.  3 A through  3 C  and  FIGS.  4 A through  4 C , the linker portion  7  and the spacer portion  6  of the holding member  4  of this embodiment are integrally molded. The linker portion  7  includes a transitional section  71  that is connected to the polygon-shaped spacer portion  6  and a shaft section  72  connected to the transitional section  71  and extending in the X-direction. Any Y-Z cross sections of the shaft section  72  taken along the X-direction are substantially the same and constant. The linker portion  7  is locked and connected to the connection member  8  by means of a locking part  73  arranged at the end  41  (see  FIG.  4 A ) of the linker portion  7  that is opposite to the end thereof connected to the spacer section  6 . The connection member  8  has a cylindrical locking protrusion  81  (see  FIG.  3 B ) at a position located vis-a-vis the linker portion  7  (of the holding member  4 ) and the locking part  73  of the linker portion  7  is locked to the locking protrusion  81 . The locking part  73  has an opening  74  on the top surface or on the bottom surface thereof so as to be mated with the locking protrusion  81 . Thus, as the locking protrusion  81  is put into and mated with the opening  74 , the holding member  4  can be made to be supported by the connection member  8  at the end  41  of the holding member  4 . 
     As shown in  FIG.  3 A , the connection member  8  is fitted to the aperture  34  of the liquid container bag  3 . Additionally, as shown in  FIG.  4 B , the connection member  8  has a first nozzle  82 A to which the second end  52  of the first tube  5 A is fitted and a second nozzle  82 B to which the second end  52  of the second tube  5 B is fitted. As the second end  52  of the first tube  5 A and the second end  52  of the second tube  5 B are respectively attached to the first nozzle  82 A and the second nozzle  82 B, the first tube  5 A is connected to the first nozzle  82 A and the second tube  5 B is connected to the second nozzle  82 B. Both the first nozzle  82 A and the second nozzle  82 B communicate with the internal flow path  83  of the connection member  8  and the ink flowing in from the first tube  5 A and the ink flowing in from the second tube  5 B join together in the internal flow path  83 . An ink supply port  84  is arranged on the surface of the connection member  8  on the side of the connection member  8  located opposite to the side of the connection member  8  where the first and second nozzles  82 A and  82 B are arranged and the ink supply port  84  is to be connected to the liquid ejection apparatus  100 .  FIG.  5 C  is a schematic cross-sectional view taken along line C-C in  FIG.  4 A . As shown in  FIG.  5 C , the first nozzle  82 A, the second nozzle  82 B and the locking protrusion  81  are flush with each other in terms of the Z-direction and the locking protrusion  81  is located between the first nozzle  82 A and the second nozzle  82 B. As shown in  FIG.  2 B , the connection member  8  is contained in a retaining member  9 . The retaining member  9  has a rotatable handle  91  (see  FIG.  1   ) and a guide section (not shown) so that the liquid container  1  can be put into and taken away from the liquid ejection apparatus  100  by grasping the handle  91  and moving the liquid container  1  along the guide section (not shown) that is provided for the cassette  2 . 
     As described above, the spacer portion  6  of the holding member  4  is provided with the first main groove  66 A, into which the first end  51  of the first tube  5 A is to be fitted, and the second main groove  67 A, into which the first end  51  of the second tube  5 B is to be fitted.  FIG.  5 A  is a schematic cross-sectional view taken along line D-D in  FIG.  3 C . In the mounted state as shown in  FIG.  5 A , the first main groove  66 Ais found in an upper part of the spacer portion  6  and the second main groove  67 A is found in a lower part of the spacer portion  6 . While the positions where the first and second main grooves  66 A and  67 A are respectively arranged are not subject to any particular limitations, preferably, the first main groove  66 A is arranged in the first top region  68 A that is located closest to the upper surface  32  of the liquid container bag  3  and the second main groove  67 A is arranged in the second top region  68 B that is located closest to the lower surface  33  of the liquid container bag  3 . Since the spacer portion  6  shows a large height (a large size as viewed in the Z-direction) in these regions, it is possible to secure a satisfactory depth for both the first main groove  66 A and the second main groove  67 A with ease. 
     The first tube  5 A and the second tube  5 B are held in position by the connection member  8  and the spacer portion  6  of the holding member  4 . It is highly preferable that the first tube  5 A is snugly fitted into the first main groove  66 A at the first end  51  thereof and the second tube  5 B is snugly fitted into the second main groove  67 A at the first end  51  thereof in order to securely and stably hold the first tube  5 A and the second tube  5 B in position. However, the part of the first tube  5 A that is to be fitted into the first main groove  66 A is not limited to the first end  51  thereof and the part of the second tube  5 B that is to be fitted into the second main groove  67 A is not limited to the first end  51  there either. In other words, the first tube  5 A may be fitted into the first main groove  66 A at any part thereof other than its second end. Similarly, the second tube  5 B may be fitted into the second main groove  67 A at any part thereof other than its second end. For example, it may be so arranged that a region of the first tube  5 A including its first end  51  projects from the first main groove  66 A in the X-direction just like a cantilever. Similarly, it may be so arranged that a region of the second tube  5 B including its second end  51  projects from the second main groove  67 A in the X-direction just like a cantilever. However, the way in which the first tube  5 A is most securely and stably held in position to eliminate a situation where ink is not drawn out reliably and stably is that the first tube  5 A is fitted into the first main groove  66 A at the first end  51  thereof and the way in which the second tube  5 B is most securely and stably held in position to eliminate a situation where ink is not drawn out reliably and stably is that the second tube  5 B is fitted into the second main groove  67 A at the first end  51  thereof 
     Preferably, the first tube  5 A is fitted into the first main groove  66 A by a length greater than its outer diameter and, similarly, the second tube  5 B is fitted into the second main groove  67 A by a length greater than its outer diameter. Assume here that the outer diameter of the first tube  5 A is D 1  and the length of the part of the first tube  5 A that is fitted into the first main groove  66 A is L 1  and that the outer diameter of the second tube  5 B is D 2  and the length of the part of the second tube  5 B that is fitted into the second main groove  67 A is L 2  as shown in  FIG.  3 C . Then, preferably, the relationships of L 1 ≥D 1  and L 2 ≥D 2  hold true. Additionally and preferably, as shown in  FIG.  5 A , the part of the first tube  5 A that is fitted into the first main groove  66 A and becomes invisible as viewed in the Y-direction has a height at least greater than a half (½) of the outer diameter of the first tube  5 A and the part of the second tube  5 B that is fitted into the second main groove  67 A and becomes invisible as viewed in the Y-direction has a height at least greater than a half (½) of the outer diameter of the second tube  5 B. Assume here that the depth by which the part of the first tube  5 A is put into the first main groove  66 A is H 1  and the depth by which the part of the second tube  5 B is put into the second main groove  67 A is H 2 . Then, preferably, the relationships of H 1 ≥D 1 / 2  and H 2 ≥D 2 / 2  hold true. As shown in  FIG.  5 B  (a cross-sectional view taken along line B-B in  FIG.  4 A ), the value of the outer diameter of the part of the first tube  5 A that is not fitted into the first main groove  66 A is given as the outer diameter D 1  of the first tube  5 A and the value of the outer diameter of the part of the second tube  5 B that is not fitted into the second main groove  67 A is given as the outer diameter D 2  of the second tube  5 B. In other words, the value of the diameter of the part of the first tube  5 A that is to be fitted into the first main groove  66 A before it is actually fitted into the first main groove  66 A may be given as the outer diameter D 1  of the first tube  5 A and the value of the diameter of the part of the second tube  5 B that is to be fitted into the second main groove  67 A before it is actually fitted into the second main groove  67 A may be given as the outer diameter D 2  of the second tube  5 B. In short, the value of the outer diameter of the first tube  5 A that is free from stress is given as D 1  and, similarly, the value of the outer diameter of the second tube  5 B that is free from stress is given as D 2 . Preferably, the first tube  5 A is pushed into the first main groove  66 A until it gets to the bottom surface of the first main groove  66 A and, similarly, the second tube  5 B is pushed into the second main groove  67 A until it gets to the bottom surface of the second main groove  67 A. Then, the depth H 1  may practically agree with the depth of the first main groove  66 A and the depth H 2  may practically agree with the depth of the second main groove  67 A. Additionally and preferably, the width of the first main groove  66 A is smaller than the outer diameter of the first tube  5 A and the width of the second main groove  67 A is smaller than the outer diameter of the second tube  5 B. Assume here that the width of the first main groove  66 A is W 1  and the width of the second main groove  67 A is W 2 . Then, preferably, the relationships of D 1 &gt;W 1  and D 2 &gt;W 2  hold true. Differently stated, the first tube  5 A is fitted into the first main groove  66 A in a state of being compressed by the first main groove  66 A and the second tube  5 B is fitted into the second main groove  67 A in a state of being compressed by the second main groove  67 A. With such an arrangement, the first tube  5 A is reliably and rigidly held in the first main groove  66 A due to the frictional force that arises between the first tube  5 A and the first main groove  66 A and the second tube  5 B is reliably and rigidly held in the second main groove  67 A due to the frictional force that arises between the second tube  5 B and the second main groove  67 A. 
     When some, preferably all, of the above-defined relationship requirements are satisfied, the first tube  5 A is reliably and stably held in the first main groove  66 A and the second tube  5 B is reliably and stably held in the second main groove  67 A so that the first tube  5 A may hardly come off from the first main groove  66 A and the second tube  5 B may hardly come off from the second main groove  67 A. As an example, both the outer diameter D 1  of the first tube  5 A and the outer diameter D 2  of the second tube  5 B are equal to  6  mm and the both the inner diameter of the first tube  5 A and the inner diameter of the second tube  5 B are equal to 4 mm, while the width W 1  of the first main groove  66 A is equal to 3 mm and the width W 2  of the second main groove  67 A is equal to 4 mm. Both the depth of the first main groove  66 A and the depth of the second main grove  67 A are equal to  6  mm and both the length L 1  of the part of the first tube  5 A that is put into the first main groove  66 A and the length L 2  of the part of the second tube  5 B that is put into the second main groove  67 A are equal to 6 mm. Even when the width W 1  of the first main groove  66 A is equal to the outer diameter D 1  of the first tube  5 A, the first tube  5 A is reliably and stably held in the first main groove  66 A so long as the first tube  5 A is held in contact with the lateral walls of the first main groove  66 A so as to give rise to friction between the first tube  5 A and the lateral walls of the first main groove  66 A. This statement is also applicable to the relationship between the width W 2  of the second groove  67 A and the outer diameter D 2  of the second tube  5 B. It is sufficient for the width W 1  of the first main groove  66 A to be not greater than the outer diameter D 1  of the first tube  5 A and for the width W 2  of the second main groove  67 A to be not greater than the outer diameter D 2  of the second tube  5 B. 
     As described earlier, ink to be used for this embodiment contains one or more than one precipitation components and, as time goes by, the concentration of the precipitation component(s) will fall in an upper part of the liquid container bag  3  and rise in a lower part of the liquid container  3 . Thus, with the above-described positional arrangement of the tubes for drawing out ink, the first tube  5 A takes in ink whose concentration of the precipitation component(s) is relatively low while the second tube  5 B takes in ink whose concentration of the precipitation component(s) is relatively high. In this operation, preferably the second tube  5 B takes in ink more than the first tube  5 A in order to prevent the rise of the concentration of the precipitation component(s) in the ink left in the liquid container bag  3 . For this purpose, as shown in  FIG.  5 A , the smallest cross-sectional area of the liquid flow path of the second tube  5 B is made greater than the smallest cross-sectional area of the liquid flow path of the first tube  5 A in this embodiment. More specifically, the cross-sectional area SB of the liquid flow path of the part of the second tube  5 B that is fitted into the second main groove  67 A is made greater than the cross-sectional area SA of the liquid flow path of the part of the first tube  5 A that is fitted into the first main groove  66 A. With this arrangement, the flow path resistance of the second tube  5 B is made smaller than the flow path resistance of the first tube  5 A so that the second tube  5 B can take in ink whose concentration of the precipitation component(s) is high with ease. Then, the ink that is found in a lower part of the liquid container bag  3  and shows a high concentration of the precipitation component(s) can efficiently be drawn into the second tube  5 B. A first tube  5 A and a second tube  5 B that have the same outer diameter and the same wall thickness are employed for the arrangement illustrated in  FIG.  5 A . With the arrangement of  FIG.  5 A , the depth H 1  of the first main groove  66 A is made to be equal to the depth H 2  of the second main groove  67 A and the width W 2  of the second main groove  67 A is made to be greater than the width W 1  of the first main groove  66 A but smaller than the outer diameter of the second tube  5 B. With the above-described arrangement, tubes having same dimensions in terms of outer diameter and wall thickness can be employed for the first tube  5 A and the second tube  5 B so that the use of such a first tube  5 A and a second tube  5 B is advantageous from the viewpoint of production management. Note, however, that the arrangement as shown in  FIG.  5 D  is also feasible. With the arrangement shown in  FIG.  5 D , the width W and the depth H of the first main groove  66 A are respectively made to be equal to the width W and the depth H of the second main groove  67 A and the outer diameter of the first tube  5 A is made to be equal to the outer diameter of the second tube  5 B. In this instance, the cross-sectional area SA of the flow path of the first tube  5 A and the cross-sectional area SB of the flow path of the second tube  5 B can be made to satisfy the relationship requirement of SB&gt;SA by making the wall thickness t 2  of the second tube  5 B smaller than the wall thickness t 1  of the first tube  5 A (and hence making the inner diameter of the second tube  5 B greater than the inner diameter of the first tube  5 A) to achieve the intended effect and provide the intended advantage. While the width of the first main groove  66 A is made to be equal to the width of the second main groove  67 A in the instance of  FIG.  5 D , the two widths may be made different from each other so long as the relationship requirement of SB&gt;SA is satisfied. Note that the width and the depth of the first main groove  66 A and those of the second main groove  67 A can appropriately be modified so long as neither of the first tube  5 A and the second tube  5 B are completely crushed and neither of their liquid flow paths are blocked. Furthermore, the outer diameter of the second tube  5 B may be made to be greater than the outer diameter of the first tube  5 A to allow more ink to flow through the second tube  5 B than through the first tube  5 A. 
     Of this embodiment, as described above, the holding member  4 , which includes the linker portion  7  and the spacer portion  6 , is made to have a configuration that is suited for integral molding so that the holding member  4  can be produced by way of a simplified manufacturing process. This advantage of this embodiment will be described by comparing this embodiment with the liquid container of the comparative example shown in  FIGS.  8 A through  8 C .  FIG.  8 A  is a schematic lateral view of the holding member  104  of the comparative example. In the liquid container of the comparative example, the spacer portion  6  is provided with additional nozzles  10 A and  10 B for respectively holding the first end  51  of the first tube  5 A and the first end  51  of the second tube  5 B. The additional nozzles  10 A and  10 B show a configuration similar to that of the first and second nozzles  82 A and  82 B of the connection member  8  shown in  FIG.  4 B . As the first and second tubes  5 A and  5 B are respectively attached to the additional nozzles  10 A and  10 B such that the first and second tubes  5 A and  5 B partly cover the additional nozzles  10 A and  10 B, the first tube  5 A and the second tube  5 B can be made to be reliable and stably held by the spacer portion  6 . 
       FIG.  8 B  shows how the holding member  104  of the comparative example is produced by injection molding. The holding member  104  can theoretically be molded by a mold having an upper mold half M 101  and a lower mold half M 102  as shown in  FIG.  5 B . The main groove  66 A and the auxiliary grooves  66 B of the spacer portion  6  are formed by the upper mold half M 101  and the lower mold half M 102 . However, in actuality, because the additional nozzle  10 A interferes with the upper mold half M 101  and the additional nozzle  10 B interferes with the lower mold half M 102 , it is not possible to produce the holding member  104  of the comparative example simply by means of the mold shown in  FIG.  8 B . Therefore, as shown in  FIG.  8 C , it is necessary to separate the spacer portion  106  and the linker portion  107  of the holding member  104  from each other and produce the spacer portion  106  and the linker portion  107  separately by means of respective dedicated molds. More specifically, the linker portion  107  is produced by using a dedicated mold having an upper mold half M 103  and a lower mold half M 104  and, similarly, the spacer portion  106  is produced by using a dedicated mold having an upper mold half M 105  and a lower mold half M 106 . Furthermore, the use of an additional partial mold M 107  that can be made to slide horizontally is required to release the mold halves M 105  and M 106  and the partial mold M 107  from the molded spacer portion  106 . Moreover, the spacer portion  106  needs to be provided with a mating section and the linker portion  107  needs to be provided with a corresponding mating section for putting the spacer portion  106  and the linker portion  107  together into a complete holding member  104 . Thus, for the holding member  104  of the comparative example, the spacer portion  106  and the linker portion  107  need to be molded by means of separate molds and then the molded spacer portion  106  and the molded linker portion  107  need to be put together to produce the complete holding member  104 . 
       FIG.  9    shows how the holding member  4  of this embodiment is produced by means of injection molding, using a mold having an upper mold half M 1  and a lower mold half M 2 . Unlike the above-described comparative example, the spacer portion  6  is not provided with any additional nozzles  10 A and  10 B. Therefore, the entire holding member  4  can be molded by means of a mold having an upper mold half M 1  and a lower mold half M 2 . Since the end  41  of the holding member  4  on the side of the connection member  8  is upwardly or downwardly open, the lower mold half M 2  can be released from the opening  74  of the end  41  without problem. Since this holding member  4  does not require additional nozzles  10 A and  10 B, the pressure loss of the holding member  4  of this embodiment is held to be very small to obtain the advantage of improving the efficiency of drawing in ink. 
     Note that the angle parts  6 C of the first main groove  66 A and the angle parts  6 C of the second main groove  67 A are made to show an angle that is suitable for conveniently releasing the mold from the spacer portion  6 . 
     The liquid container  1  can be manufactured by way of the manufacturing process that will be described below. First, the holding member  4  is integrally formed by way of the above-described process. Then, the holding member  4  is fitted to the connection member  8  as indicated by way of the process step P 1  shown in  FIG.  2 B  and  FIG.  3 B . Thereafter, the second end  52  of the first tube  5 A and also the second end  52  of the second tube  5 B are fitted to the connection member  8  as indicated by the process step P 2  shown in  FIG.  3 B  and  FIG.  4 B . Subsequently, the first tube  5 A is fitted into the first main groove  66 A of the spacer portion  6  at the first end  51  thereof and the second tube  5 B is fitted into the second main groove  67 A of the spacer portion  6  also at the first end  51  thereof as indicated by process step P 3  in  FIG.  3 B  and  FIG.  4 B . While it is preferable that the process step P 2  is executed first and the process step P 3  is executed thereafter from the viewpoint of causing the holding member  4  to reliably and securely hold the first and second tubes  5 A and  5 B, the process step P 3  may alternatively be executed before the execution of the process step P 2 . Then, the connection member  8  is fitted to the retaining member  9  as indicated by the process step P 4  in  FIG.  2 B  and  FIG.  3 B . Now, the operation of assembling the holding member  4 , the connection member  8 , the first and second tubes  5 A and  5 B, which are held by the holding member  4  and the connection member  8 , and the retaining member  9  is completed. Thereafter, the holding member  4  and the first and second tubes  5 A and  5 B are arranged in the inner space  31  of the liquid container bag  3  such that both the first end  51  of the first tube  5 A and the first end  51  of the second tube  5 B are held open in the inner space  31  of the liquid container bag  3  as indicated by the process step P 5  in  FIG.  2 B . Subsequently, the aperture  34  of the liquid container bag  3  that is fitted to the outer surface of the connection member  8  is hermetically sealed. The manufacturing of the liquid container  1  is completed as a result of the above-described process steps. When mounting the liquid container  1  in the liquid ejection apparatus  100 , the liquid container  1  is put into the cassette  2  as indicated by the process step P 6  in  FIG.  2 B . Then, the cassette  2  now bearing the liquid container  1  is driven to slide into the liquid ejection apparatus  100  in the X-direction to complete the operation of mounting the cassette  2  into the liquid ejection apparatus  100 . 
     The holding member of a liquid container according to the present disclosure is realized by modifying the known structure of the part of the holding member where the tubes are fitted to the holding member so as to allow the holding member to be integrally molded. Thus, the present disclosure provides a liquid container including a holding member showing an improved ink supply performance. The present disclosure also provides a method of manufacturing a holding member to be used in a liquid container that allows the holding member to be molded by integral molding. 
     While the present disclosure has been described with reference to exemplary embodiments, it is to be understood that the disclosure is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.