Patent Publication Number: US-6986569-B2

Title: Ink cartridge and its manufacturing method

Description:
This is a continuation of U.S. patent application Ser. No. 10/246,757 filed Sep. 19, 2002, U.S. Pat. No. 6,796,642, the disclosure of which is incorporated by reference. 

   BACKGROUND OF THE INVENTION 
   The present invention relates to an ink cartridge and its manufacturing method. Particularly, the invention relates to an ink cartridge which supplies ink to an ink jet recording apparatus through an ink supply needle of the ink jet recording apparatus. 
   There is an ink jet recording apparatus in which an ink cartridge is detachably mounted onto a carriage having an ink jet recording head thereby to supply ink. As an example of this ink cartridge, there is an ink cartridge having an outline of an approximately rectangular parallelepiped, in which a porous member including ink therein is housed. In this ink cartridge, since the ink is held into the ink cartridge, negative pressure is generated inside the ink cartridge. 
   This type of ink cartridge is made up of a container body having a shape of an approximately rectangular parallelepiped and the opened upper surface. The container body is provided, at its bottom surface, with an ink supply passage into which an ink supply needle of the ink jet recording apparatus is inserted. The porous member is inserted into the container body from the upper surface, and the upper surface is sealed by a lid member, whereby the ink cartridge is manufactured. 
   The porous member is inserted into the container body from the upper surface in order to press a portion of the porous member near the ink supply passage against the ink supply passage and the ink supply surface thereby to compress this portion of the porous member. The higher the density of the porous member becomes due to compression, the stronger its capillary power becomes, so that the compressed porous member can collect ink. Therefore, in order to decrease a shortage of ink supply, the above manufacturing method is used so that ink can be collected to the portion of the porous member near the ink supply surface. 
   However, in an On-carriage type of ink jet recording apparatus in which an ink cartridge is mounted onto a movable carriage having an ink recording head, in order to mount as many ink cartridges as possible on the carriage, there is a tendency to reduce the width of the ink cartridge in the scanning direction of the carriage. Particularly, a color ink jet recording apparatus can mount ink cartridges holding ink of four or more colors in order to improve color reproduction. In this case, it is desirable that the width of the ink cartridge in the carriage moving direction is made as small as possible in order to make the width of the recording apparatus small and further the height of each ink cartridge is several times as large as the width thereof in order to secure the enough ink capacity. 
   For the ink cartridge that is thus high and narrow, it is difficult to insert the porous member into the container from the upper surface of the container. Namely, the porous member has compressibility, and it is not easy to insert such the porous member into the narrow and long space where friction is large. 
   Therefore, an object of the invention is to provide an ink cartridge which can solve the above problem and its manufacturing method. 
   Further, the above ink cartridge of which the height is larger than the width thereof is weak in mechanical strength in the width direction. Namely, in the side surface of the ink cartridge, its surrounding portion is only connected to other surfaces. Therefore, regarding the side surface having the large height and large area, its central portion is not supported by any members. Consequently, in case that pressure reduction is performed by letting air out of the inside of the ink cartridge in order to make the inside of the ink cartridge in a negative pressure state, the side surface having this large area is easy to deform. In case that this deformation exceeds an allowable size of the cartridge, there is fear that the ink cartridge is broken. Further, in case that the user or the like holds the central portions of the side surfaces of the ink cartridge opposed to each other so as to pinch them, that is, in case that the strong power is applied to these portions, there is fear that the ink cartridge is broken. 
   Therefore, it is another object of the invention to provide an ink cartridge which can solve the above problem. 
   SUMMARY OF THE INVENTION 
   According to the invention, in manufacture of an ink cartridge, a porous member is inserted into a container body from an opening surface side. Accordingly, insertion of the porous member is easy. Further, after a portion of the porous member near an ink supply passage is pressed against a pressure-contacting portion and compressed, the porous member is inserted into the container body. Therefore, ink collects around the ink supply passage, so that it is possible to provide an ink cartridge that supplies ink stably. 
   According to the invention, a reinforcing structure is provided for the inside of ink cartridge. Therefore, the mechanical strength of the ink cartridge in the width direction can be reinforced. Further, the porous member has a shape avoiding the reinforcing structure and surrounding it. Therefore, it is possible to prevent ink from collecting unnecessarily around the reinforcing structure. As the reinforcing structure, rib is preferable. 
   The present disclosure relates to the subject matter, contained in Japanese patent application Nos. 2001-285082 and 2001-285083 (both filed on Sep. 19, 2001), which are expressly incorporated herein by reference in their entireties. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a front perspective view of an ink cartridge according to a first embodiment of the invention; 
       FIG. 2  is a rear perspective view of the ink cartridge in  FIG. 1 ; 
       FIG. 3  is an exploded perspective view of the ink cartridge in the first embodiment; 
       FIG. 4A  is a perspective view showing an initial state for explaining a manufacturing method of the ink cartridge in the first embodiment, and  FIG. 4B  is a sectional view of a portion near an ink supply passage  16  in  FIG. 4A , taken in parallel to the inserting direction of an ink needle; 
       FIG. 5  is a perspective view showing a porous member to be inserted into a container body; 
       FIG. 6  is a sectional view showing a first step of a process for inserting the porous member into the container body; 
       FIG. 7  is a sectional view showing a second step of the process for inserting the porous member into the container body; 
       FIGS. 8A and 8B  are sectional views showing the states where the porous member is housed into the container body; 
       FIG. 9  is a sectional view showing the state where a lid member is attached to the container body; 
       FIG. 10A  is a perspective view showing an initial state for explaining a manufacturing method of an ink cartridge in a second embodiment, and  FIG. 10B  is a sectional view of a portion near an ink supply passage in  FIG. 10A , taken in parallel to the inserting direction of an ink needle; 
       FIGS. 11A and 11B  are diagram showing stepwise the manufacturing method of the ink cartridge in the second embodiment; 
       FIG. 12A  is a perspective view showing an initial state for explaining a manufacturing method of an ink cartridge in a third embodiment, and  FIG. 12B  is a sectional view of a portion near an ink supply passage in  FIG. 12A , taken in parallel to the inserting direction of an ink needle; 
       FIGS. 13A and 13B  are diagram showing stepwise the manufacturing method of the ink cartridge in the third embodiment; 
       FIG. 14  is an exploded perspective view of an ink cartridge in a fourth embodiment; 
       FIG. 15A  is a perspective view of a container body of the cartridge in  FIG. 14 , and  FIG. 15B  is a front schematic view in which the container body in  FIG. 15A  is viewed from the direction of an opening surface; 
       FIG. 16  is a perspective view of a porous member to be housed in a space formed by a container body and a lid member; 
       FIG. 17A  is a side view in which the state where the porous member is housed in the container body is viewed from the opening surface side of the container body, and  FIG. 17B  is a sectional view in which the state in  FIG. 17A  is viewed from the direction orthogonal to the opening surface; 
       FIG. 18A  is a perspective view of a container body of a cartridge in a fifth embodiment, and  FIG. 18B  is a front schematic view in which the container body in  FIG. 18A  is viewed from the direction of an opening surface; 
       FIG. 19  is a perspective view of a porous member to be housed in the cartridge in the fifth embodiment; and 
       FIG. 20A  is a side view in which the state where the porous member is housed in the container body is viewed from an opening surface side of the container body, and  FIG. 20B  is a sectional view in which the state in  FIG. 20A  is viewed from the upside. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Though the invention according to claims will be described below with reference to embodiments, it is not limited to the following embodiments, and all the combinations of features described in the embodiments are not essential to means for solving the invention. 
     FIG. 1  is a front perspective view of an ink cartridge according to a first embodiment of the invention.  FIG. 2 . is a rear perspective view of the ink cartridge in  FIG. 1 . An ink cartridge  10  includes a container body  12  and a lid member  14 , and has an outline of an approximately rectangular parallelepiped as a whole. The container body  12  has an ink supply surface  18  including an ink supply passage  16  into which an ink supply needle of an ink jet recording apparatus is inserted. 
   In the vicinity of the ink supply passage  16  and on a center side of the container body, there is provided a slit portion  30  extending from the ink supply surface  18  of the container body  12  in the inserting direction of the ink supply needle. By this slit portion  30 , the insertion of the ink supply needle into the ink cartridge  10  is regulated so that an opening surface of the ink supply passage  16  is orthogonal to the ink supply needle before the leading end of the ink supply passage  16  reaches the ink supply needle, so that the ink supply needle can be surely inserted into the ink supply passage  16 . 
   Further, at the upper portions of side surfaces of the container body  12 , fitting members  32  and  34  respectively fitting to a carriage of the ink jet recording apparatus are formed integrally with the container body  12 . 
     FIG. 3  is an exploded perspective view of the ink cartridge  10  in the first embodiment. The ink cartridge  10  includes the above container body  12  and the lid member  14 , and further includes a porous member  20  to be housed in the space formed by the container body  12  and the lid member  14 , and a pressure-contacting portion  22  provided in the vicinity of the ink supply passage  16  in parallel to the ink supply surface. 
   The container body  12  has a shape of an approximately rectangular parallelepiped in which one side surface is opened. In the container body  12 , the ink supply passage  16  communicating from the outside of the container body  12  to the inside thereof is provided on the ink supply surface  18 . The slit portion  30  forms a convex portion extruding inward of the container body  12 . In a side surface  26  approximately orthogonal to the ink supply surface  18  of the container body  12 , its height h is larger than at least one width w of the ink supply surface  18 . As described above, in the On-carriage type ink jet recording apparatus, since as many ink cartridge as possible are mounted on the carriage, the width of the ink cartridge in the carriage scanning direction is frequently made small. For example, the height of the ink cartridge becomes several times as large as the width thereof. Correspondingly, the height h of the container body  12  is also made several times as large as the width w thereof. 
   One of the side surfaces of the container body  12  having the shape of the approximately rectangular parallelepiped is opened in this width direction thereby to form an opening surface  28 . In this embodiment, the opening surface  28  is one of surfaces having the largest area in six surfaces constituting the approximately rectangular parallelepiped shaped container body  12 . Hereby, it is easy to insert the porous member  20  into the container body  12  from the opening surface  12 . 
   The container body  12  further includes a vent hole  36 . communicating with the air. The air is brought through this vent hole  36  into the ink cartridge  10 , and ink is supplied through the ink supply passage  16  from the inside of the ink cartridge  10  to the ink jet recording apparatus. Further, the vent hole  36  is preferably sealed by a film having ink-repellent property and gas-permeability. Further, the vent hole  36  may be connected to a capillary so that the inside of the ink cartridge  10  is communicated with the air through the capillary. 
   The lid member  14  is a plate-like member having the approximately same shape as the opening surface  28  of the container body  12 . The lid member  14  is welded to the container body  12  and seals the opening surface  28  of the container body  12 . Further, a film may be applied onto the opening surface  28  of the container body  12  and thereafter the lid member  14  may be welded to the container body  12  from the film side. Hereby, the space inside the ink cartridge  10  can be surely sealed. 
   The porous member  20  has many small pores therein, and ink is held in these small pores by the capillary power. Though, this porous member  20  has a shape of a rectangular parallelepiped as described later, it is shown in  FIG. 3  in a deformed state in which the porous member  20  is pressure-contacted by the pressure-contacting portion  22  and housed into the container body  12 . 
   The pressure-contacting portion  22  is a plate-like member provided on the ink supply passage  16  in parallel to the ink supply surface  18 . In this embodiment, the pressure-contacting portion  22  is a member discrete from the container body  12 . However, the invention is not limited to this, but the pressure-contacting portion  22  may be molded integrally with the container body  12 . The pressure-contacting portion  22  has, in its position corresponding to the ink supply passage  16 , a filter  24  through which ink from the porous member  20  passes. This filter  24  can prevent foreign matter included in the ink from getting mixed in the ink jet recording apparatus by filtering the foreign matter. 
     FIG. 4A  is a perspective view showing an initial state in order to explain a manufacturing method of the ink cartridge  10  in the first embodiment.  FIG. 4B  is a sectional view of a portion near an ink supply passage  16  in  FIG. 4A , taken in parallel to the inserting direction of an ink needle, and  FIG. 4B  is shown simply in order to make the explanation easy. In these figures, a container body  12 , similarly to that shown in  FIG. 3 , has a shape of an approximately rectangular parallelepiped including an ink supply surface  18 , in which the height of a side surface  26  approximately orthogonal to the ink supply surface  18  is larger than at least one width of the ink supply surface  18 , and one of the side surfaces is opened to provide an opening surface  28 , and the container body  12  is molded integrally. Further, a pressure-contacting portion  22  having a filter  24  is provided on the ink supply passage  16  in parallel to the ink supply surface 
     FIG. 5  is a perspective view showing a porous member  20  to be inserted into the container body  12 . The porous member  20  has a shape of a rectangular parallelepiped that is the approximately same as the container body  12 . From  FIG. 5  on, spots shown in the porous member  20  represent a density of the porous member. In the figure, a portion where spots are shown densely, in which the porous member  20  is compressed and dense, indicates that capillary power is strong. 
     FIG. 6  is a sectional view showing a first step of a process for inserting the porous member  20  into the container body  12 . Firstly, a portion  33  of the porous member  20  near the ink supply surface  18  is pressed toward the ink supply surface  18  in the direction of an arrow A. More particularly, the portion  33  of the porous member  20  is pressed from the slanting upside of the opening surface  28  against the pressure-contacting portion  22  provided in the vicinity of the ink supply passage  16  in parallel to the ink supply surface  18 . 
     FIG. 7  is a sectional view showing a second step of the process for inserting the porous member  20  into the container body  12 . Sequentially to the first step in  FIG. 6 , the portion  33  of the porous member  20  near the ink supply surface  18  is pressed in the direction of an arrow A thereby to compress more this portion  33 . After the porous member  20  has been compressed so that the height of the porous member  20  becomes the same as the length between the pressure-contacting portion  22  and the upper surface of the container body  12 , the whole of the porous member  20  is inserted into the container body  12  so as to be turned in the direction of an arrow B. 
     FIGS. 8A and 8B  show the states where the porous member  20  is housed into the container body  12 .  FIG. 8A  is a sectional view, and  FIG. 8B  is a sectional diagram viewed from the direction orthogonal to  FIG. 8A . The porous member  20  is pressed against the pressure-contacting portion  22  and inserted into the container body  12 . In the housing state, the porous member  20  around the pressure-contacting portion  22  is compressed. In case that the porous member  20  has been compressed, a pore diameter of the small pore becomes small, so that the capillary power becomes stronger. Namely, the compressed portion is stronger in ink holding power than the no-compressed portion. Therefore, the ink held in the porous member  20  is easy to collect at the compressed portion around the pressure-contacting portion  22 . Hereby, the ink is incessantly supplied from the porous member  20  through the ink supply passage  16  to the ink jet recording apparatus. 
     FIG. 9  is a sectional view showing the state where a lid member  14  is attached to the container body  12 . From the states shown in  FIGS. 8A and 8B , the lid member  14  is attached to the container body  12  so as to seal the opening portion  28 . As an example of this attachment, the lid member  14  is attached to the container body  12  by vibration-welding. Hereby, the porous member  20  is housed in the sealed space. 
   After the lid member  14  has been attached to the container body  12 , the ink cartridge  10  is placed in a pressure reduction room in which pressure is reduced, and the space surrounded by the container body  12  and the lid member  14  is pressure-reduced. Ink is put into the pressure-reduced space surrounded by the container body  14  and the lid member  14  from, for example, the ink supply passage  16  thereby to permit the porous member  20  to include the ink. As described above, the ink cartridge  10  is manufactured. 
   According to the first embodiment, the opening surface is one of the surfaces having the largest area in six surfaces constituting the approximately rectangular parallelepiped-shaped container body, and in the ink cartridge manufacturing method, the porous member is inserted into the container body from this opening surface side. Therefore, the insertion of the porous member is easy. Further, after the portion of the porous member near the ink supply passage has been pressed against the pressure-contacting portion and compressed, the porous member is inserted into the container body. Therefore, the ink collects around the ink supply passage, so that it is possible to provide an ink cartridge which supplies ink stably. 
     FIG. 10A  is a perspective view showing an initial state in order to explain a manufacturing method of an ink cartridge  40  in a second embodiment.  FIG. 10B  is a sectional, view of a portion near an ink supply passage  46  in  FIG. 10A , taken in parallel to the inserting direction of an ink needle, and  FIG. 10B  is shown simply in order to make the explanation easy. In these figures, parts similar to those in the first embodiment shown in  FIG. 1  are denoted by the same reference numerals. 
   In a container body  42  of the ink cartridge  40  in the second embodiment, a pressure-contacting portion  48  perpendicular to an ink supply surface  18  is provided on the ink supply passage  46 . The pressure-contacting portion  48  has on its both sides horizontal plates  52  and  54  which are parallel to the ink supply surface  18  and different in height from each other. A filter  50  is provided for a portion of the pressure-contacting portion  48  corresponding to the ink supply passage  46 . 
     FIGS. 11A and 11B  are diagram showing, step-by-step, the manufacturing method of the ink cartridge  40  in the second embodiment. As shown in  FIG. 11A , a porous member  20  is inserted into the container body  42  from an opening surface  28  of the ink cartridge  40 . In this case, similarly to in the first embodiment, the porous member  20  may be pressed from the slanting upside of the opening surface  28  and thereafter inserted into the container body  42  completely. 
   However, the pressure-contacting portion  48  of the ink cartridge  40  in the second embodiment is provided on the ink supply surface  18  perpendicularly. Accordingly, the porous member  20  may be inserted from an opening of the opening surface  28  in the direction of an arrow D while a portion of the porous member  20  near the ink supply passage  18  is being pressed against the pressure-contacting portion  48 . Thereafter, a lid member  14  is welded to the opening surface  28  of the container body  42  in the direction of an arrow E. 
   As shown in  FIG. 11B , in the thus housed porous member  20 , the portion of the porous member near the ink supply passage  18  is pressed against the pressure-contacting portion  48  and compressed. Hereby, ink collects near this portion, and ink can be supplied to the ink jet recording apparatus without causing a shortage of ink. 
   According to the second embodiment, the similar effects to those in the first embodiment can be obtained. Further, since the pressure-contacting portion in the second embodiment is perpendicularly provided on the ink supply surface, in case that the porous member is inserted from the opening direction of the opening surface, the porous member is pressed against the pressure-contacting portion and compressed. Hereby, insertion of the porous member is easier, so that it is possible to manufacture an ink cartridge which supplies ink stably. 
     FIG. 12A  is a perspective view showing an initial state in order to explain a manufacturing method of an ink cartridge  60  in a third embodiment.  FIG. 12B  is a sectional view of a portion near an ink supply passage  66  in  FIG. 12A , taken in parallel to the inserting direction of an ink needle, and  FIG. 12B  is shown simply in order to make the explanation easy. In these figures, parts similar to those in the first embodiment shown in  FIG. 1  are denoted by the same reference numerals. 
   In a container body  62  of the ink cartridge  60  in the third embodiment, a pressure-contacting portion  64  inclining with respect to an ink supply surface  18  is provided on the ink supply passage  66 . The pressure-contacting portion  64  inclines so that a side surface  26  side becomes higher than an opening surface  28  side. A filter  67  is provided for a portion of the pressure-contacting portion  64  corresponding to the ink supply passage  66 . 
     FIGS. 13A and 13B  are diagram showing, step-by-step, the manufacturing method of the ink cartridge  60  in the third embodiment. As shown in  FIG. 13A , a porous member  20  is inserted into a container body  62  from the opening surface  28  of the ink cartridge  60 . In this case, similarly to in the first embodiment, the porous member  20  may be pressed from the slanting upside of the opening surface  28  and thereafter inserted into the container body  62  completely. 
   However, the pressure-contacting portion  64  of the ink cartridge  60  in the third embodiment is provided on the ink supply surface  18  with an inclination. Accordingly, the porous member  20  may be inserted from an opening of the opening surface  28  in the direction of an arrow D while a portion of the porous member  20  near the ink supply passage  18  is being pressed against the pressure-contacting portion  64 . Thereafter, a lid member  14  is welded to the opening surface  28  of the container body  62  in the direction of an arrow E. 
   As shown in  FIG. 13B , in the thus housed porous member  20 , the portion of the porous member near the ink supply passage  18  is pressed against the pressure-contacting portion  64  and compressed. Hereby, ink collects near this portion, and ink can be supplied to the ink jet recording apparatus without causing a shortage of ink. 
   According to the third embodiment, the similar effects to those in the first embodiment can be obtained. Further, since the pressure-contacting portion in the third embodiment is provided on the ink supply surface with an inclination, in case that the porous member is inserted from the opening direction of the opening surface, the porous member is pressed against the pressure-contacting portion and compressed. Hereby, insertion of the porous member is easier, so that it is possible to manufacture an ink cartridge which supplies ink stably. 
   In each of the first to third embodiments, it is preferable that a reinforcing structure is provided in the ink cartridge in order to reinforce mechanical strength of the ink cartridge in its width direction. Taking the first embodiment as an example, embodiments in which the reinforcing structure is provided will be described below. In the following embodiments, as a preferable example of the reinforcing structure, a rib is taken. However, the invention is not limited to this. 
     FIG. 14  is an exploded perspective view of an ink cartridge  10  in a fourth embodiment. 
   In the space formed by a container body  12  and a lid member  14 , a rib  41  is provided, which reinforces mechanical strength of the ink cartridge  10  in its width direction. 
   A porous member  20 , as described later, has a shape of a rectangular parallelepiped including a slit  51  corresponding to the rib  41  of the container body  12 . However, in  FIG. 14 , the porous member  20  is shown in a deformed state where it is pressure-contacted by a pressure-contacting portion  22  and housed in the container body  12 . 
   The container body  12  has the rib  41  provided in parallel to an ink supply surface  18 . The rib  41  is formed integrally with the container body  12  in this embodiment. This rib  41  extends from a side near an ink supply passage  16 , that is, a left side in  FIG. 15B  to a side far from the ink supply passage  16 , that is, a right side in  FIG. 15B . An end portion of the rib  41  far from the supply passage  16  is not connected to the container body  12  to form a communicating passage  43 . 
   The container body  12  has the rib  40  provided in parallel to an ink supply surface  18 . The rib  40  is formed integrally with the container body  12  in this embodiment. This rib  40  extends from a side near an ink supply passage  16 , that is, a left side in  FIG. 15B  to a side far from the ink supply passage  16 , that is, a right side in  FIG. 15B . An end portion of the rib  16  far from the supply passage  16  is not connected to the container body  12  to form a communicating passage  42 . 
     FIG. 16  is a perspective view of the porous member  20  housed in the space formed by the container body  12  and the lid member  14 . The porous member  20  has a shape of a rectangular parallelepiped that is the approximately same as the shape of the container body  12 . The porous member  20  further has the slit  51  at its portion corresponding to the rib  41  of the container body  12 . One end of this slit  51  is opened, and the other end thereof is not opened but forms a connecting portion  53  that connects a upper half and a lower half of the porous member  20 . Since the upper half and the lower half are connected physically by the connecting portion  53 , the porous member can be handled as a single member, so that it is easy to handle the porous member in a manufacturing process and the like. 
     FIG. 17A  is a side view in which the state where the porous member  20  is housed in the container body  12  in the ink cartridge  10  is viewed from the opening surface  28  side of the container body  12 . However, for explanation, the lid member  14  is not shown.  FIG. 17B  is a sectional view in which the state in  FIG. 17A  is viewed from the direction orthogonal to the opening surface  28 . 
   The porous member  20  of which the outline is approximately a rectangular parallelepiped is compressed at its portion pressure-contacted to the pressure-contacting portion  22 , and inserted into the container body  12 . The capillary power of a portion of the porous member  20  where is near the ink supply passage  16  becomes high by this compression, so that ink collects at this portion. Therefore, the ink can be supplied to the outside without causing a shortage of ink. With the insertion of this porous member  20  into the container body  12 , the rib  41  of the container body  12  is inserted into the slit  51  of the porous member  20 . Further, the connecting portion  53  of the porous member  20  is inserted into the communicating portion  43  of the container body  12 . Hereby, the porous member  20  is housed in the space formed by the container body  12  and the lid member  14  so as to evade the rib  41  and surround it. 
   The lid member  14  is joined to the container body  12  as to seal the opening surface  28 . In this case, in the embodiment, an end portion of the rib  41  is also joined to the lid member  14 . Hereby, the mechanical reinforcement by the rib  41  becomes stronger. 
   After the lid member  14  has been joined to the container body  12 , the ink cartridge  10  is placed in a pressure reduction room in which pressure is reduced, and the space surrounded by the container body  12  and the lid member  14  is pressure-reduced. Ink is put into the pressure-reduced space surrounded by the container body  14  and the lid member  14 , for example, from the ink supply passage  16  thereby to permit the porous member  20  to include the ink. As described above, the ink cartridge  10  is manufactured. 
   According to the above fourth embodiment, the mechanical strength of the ink cartridge  10  in the direction of an arrow A in  FIG. 17B  can be reinforced by the rib  41 . Further, since the rib  41  is inserted into the slit  51 , the porous member  20  is not compressed around the rib  41 , so that it is possible to prevent ink from unnecessarily concentrating in this portion. Further, in the ink cartridge  10 , as much ink as possible can be held by the porous member  20  in the space formed by the container body  12  and the lid member  14 . 
   In the fourth embodiment, though the rib  41  is provided in parallel to the ink supply surface, the invention is not limited to this. As another example, the rib  41  may be provided perpendicularly to the ink supply surface  18 . 
   Further, in the fourth embodiment, though the rib  41  of the container body  12  is joined to the lid  14 , the invention is not limited to this. As another example, when the lid member  14  is joined to the container body  12 , a gap may be provided between the rib  41  and the lid member  14 . 
     FIG. 18A  is a perspective view of a container body  62  of a cartridge  60  in a fifth embodiment, and  FIG. 18B  is a front schematic view in which the container body  62  in  FIG. 18A  is viewed from the direction of an opening surface  28 . Parts similar to those of the ink cartridge in the fourth embodiment are denoted by the same reference numerals, and their explanation in omitted. 
   In the ink cartridge  60  according to the fifth embodiment, a rib  65  is provided perpendicularly to an ink supply surface  18 . The rib  65  is formed integrally with the container body  62 , extends perpendicularly downward from the inside of the upper surface of the container body, and includes a communicating portion  66  between it and the lower surface of the container body  62 . The width d of the rib  65  is smaller than the inner width w′ of the container body  62 . The inside of the container body  62  is nearly divided into a first room  68  and a second room  69  by this rib  65 . 
     FIG. 19  is a perspective view of a porous member  70  to be housed into the cartridge  60  in the fifth embodiment. This porous member  70  has a first porous member  71  and a second porous member  72  that are two individual members. The first porous member  71  has a shape of a rectangular parallelepiped that is the approximately same as the shape of the first room  68  of the container body  62 . The second porous member  72  has a shape of a rectangular parallelepiped that is the approximately same as the shape of the second room  69  of the container body  62 . The first porous member  71  and the second porous member  72  that are divided at a portion corresponding to the rib  65  of the container body  62  are combined, whereby the porous member  70  has a shape of a rectangular parallelepiped that is the approximately same as the shape of the container body  62  as a whole. 
   The first porous member  71  and the second porous member  72  may be made of the same material or may be made of the different material from each other. As an example of the different material, the first porous member  71  to be inserted into a portion near an ink supply passage  16  uses a material that is high in density and small in diameter of a small pore. On the other hand, the second porous member  72  uses a material that is low in density and large in diameter of the small pore. Hereby, while ink is concentrated in the first room near the ink supply passage  16  and a shortage of ink is prevented, a large quantity of ink can be held in the second room. 
   Further, the first porous member  71  and the second porous member  72  may be made of the same material and may be of the same size to obtain necessary effects. In this case, without increasing the number of kinds of parts, the ink cartridge can be readily manufactured. 
     FIG. 20A  is a side view in which the state where the porous member  70  is housed in the container body  62  in the ink cartridge  60  is viewed from an opening surface  28  side of the container body  62 . However, for explanation, a lid member  14  is not shown.  FIG. 20B  is a sectional view in which the state in  FIG. 20A  is viewed from the upside. 
   As shown in  FIG. 20A , the first porous member  71  is inserted into the first room  68 , the second porous member  72  is inserted into the second room  69 , and the first and second porous members  71  and  72  come into contact with each other at the communicating portion  66 . Under this state, the lid member  14  is joined to the opening surface  28  thereby to seal the porous member  70 . 
   In this embodiment, since the width d of the rib  65  is smaller than the inner width w′ of the container body  62 , as shown in  FIG. 20B , a gap  74  is formed between the rib  65  and the lid member  14 . Therefore, when the lid member  14  is joined to the container body  62 , the rib  65  is not joined to the lid member  14 . Even if there is the rib  65 , the joint portion between the container body  62  and the lid member  14  does not increase. Therefore, the ink cartridge  60  is readily manufactured. 
   As described above, according to the fifth embodiment, in the ink cartridge  60 , the rib  65  can reinforce the mechanical strength in the direction of an arrow B in  FIG. 20B . Further, though there is the gap  74  between the lid  14  and the rib  65 , elasticity of the container body  62  or the lid  14  permits first deformation, and at the time of the next deformation, the rib  65  and the lid member  14  come into contact with each other thereby to substantially secure the mechanical strength. 
   Further, according to the fifth embodiment, in the ink cartridge  60 , the porous member  70  is divided at its portion corresponding to the rib  65  into the first porous member  71  and the second porous member  72  that are the individual members. Therefore, around the rib  65 , any of the porous members  71  and  72  are not compressed, and it is possible to prevent ink from unnecessarily concentrating on this portion. Further, as much ink as possible can be held by the first and second porous members  71  and  72  in the space formed by the container body  62  and the lid member  14 . 
   In the fifth embodiment, though there is the gap  74  between the rib  65  and the lid  14 , the width of the rib  65  may be made large to join the rib  65  to the lid member  14  similarly to in the fourth embodiment. 
   Further, in the fifth embodiment, though the porous member  70  is divided into the plural porous members, the slit may be provided for the integral porous member  70  similarly to in the fourth embodiment. 
   In either of the fourth and fifth embodiments, though the rib is formed integrally with the container body, the invention is not limited to this. As another example, there is a rib formed integrally with a lid member. Also, as other examples, a rib may be joined to a container body, or a gap may be provided between a rib and a container body. 
   Further, in the fourth and fifth embodiments, though the single rib is provided, the invention is not limited to this. Namely, a plurality of ribs may be provided. 
   Although the invention has been described with reference to the embodiments, the technical scope of the invention is not limited to the scope described in the above embodiments. Various changes or modifications can be added to the above embodiments. It is clear from the description of the scope of the patent claims that the embodiment to which such changes or modifications has been added can be also included in the technical scope of the invention.