Patent Publication Number: US-7222949-B2

Title: Method for manufacturing liquid cartridge and a liquid cartridge

Description:
The present application claims priority from Japanese Patent Applications 2002-358763 filed on Dec. 10, 2002 and 2003-204740 filed on Jul. 31, 2003, the contents of which are incorporated herein by reference. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a method for manufacturing a liquid cartridge and a liquid cartridge. More particularly, the present invention relates to a method for manufacturing a liquid cartridge and a liquid cartridge, which has a supply valve in a liquid supplying part. 
   2. Description of the Related Art 
   The ink cartridge holds ink therein and supplies the ink held therein to a recording head of an inkjet type recording apparatus when mounted onto a carriage equipped with the recording head. In the ink cartridge, a supply valve and a seal member for being in contact with the supply valve are provided in an ink supply section into which an ink supply needle of the inkjet type recording apparatus is inserted. In a state where the ink cartridge is not mounted on the carriage, the supply valve seals the seal member so that the ink does not leak out from the ink cartridge. In addition, in a state where the ink cartridge is mounted on the carriage, since the ink supply needle of the inkjet type recording apparatus moves the supply valve, the supply valve opens the seal member, and thus the ink is supplied to the recording head. For example, as a supply valve of the ink cartridge, a ball valve has been used as disclosed in Japanese Patent Application Publication No. 5-229137. Further, the ink cartridge, the inkjet type recording apparatus and the recording head here are an example of the liquid cartridge, the liquid ejecting apparatus and the ejecting head. 
   However, in the ball-shaped supply valve, there is a possibility that the ink supply needle is not always in contact with the center part of the ball-shaped supply valve, so, in this case, the supply valve cannot move in a supply-needle-insertion direction of the ink supply needle because it turns around. For this reason, there is a possibility that the supply valve is not opened and the ink cannot be supplied even though the ink supply needle is in contact with the supply valve. 
   Further, when the ball-shaped supply valve is mounted on the ink cartridge, a coil spring is inserted into the ink supply section and then the ball-shaped supply valve is inserted into the ink supply section into which the coil spring has been inserted. Next, the supply valve is temporarily stopped by a fixture in a state where the ball-shaped supply valve urged by the coil spring is pushed inwardly, and then a seal member is fitted into an ink supplying opening. After that, the fixture is removed from the ink cartridge. Consequently, the supply valve closes the ink supplying opening by an urging force of the coil spring. The method for assembling the ink supply section above is difficult and also takes time to assemble because of using the fixture. Therefore, there is a problem that the production cost of the ink cartridge becomes increased. 
   In addition, when the fixture is inserted into the ink supply section in order to fill ink during a process of filling ink, it is impossible to attach a film or the like for preventing the seal member from being fallen off, so that there is a problem that the seal member is fallen off or tilted by the urging force from when the seal member is fitted to when the film for preventing falling off is attached. 
   SUMMARY OF THE INVENTION 
   Therefore, it is an object of the present invention to provide a method for manufacturing a liquid cartridge and a liquid cartridge, which are capable of overcoming the above drawbacks accompanying the conventional art. The above and other objects can be achieved by combinations described in the independent claims. The dependent claims define further advantageous and exemplary combinations of the present invention. 
   According to the first aspect of the present invention, a method for manufacturing a liquid cartridge comprising a liquid accommodating chamber for containing therein a liquid, a hollow part having a liquid supplying opening, into which a liquid supplying needle of a liquid ejecting apparatus is inserted, while the liquid supplying opening communicates with the liquid accommodating chamber, a seal member contained in the hollow part, the seal member having an insertion opening being in elastic contact with an external circumference of the liquid supplying needle, while the liquid supplying needle is inserted into the insertion opening, a supply valve contained in the hollow part, the supply valve arranged in order to close or open the insertion opening of the seal member and an urging member for urging the supply valve toward the seal member, the method comprises an urging member insertion step of inserting the urging member into the hollow part from the liquid supplying opening, a seal member mounting step of mounting the seal member in the liquid supplying opening and a supply valve insertion step of inserting said supply valve into said hollow part from said insertion opening of said seal member mounted in said liquid supplying opening inserted during said seal member mounting step, and forming a state where said supply valve is pressed by an urging force of said urging member. 
   Due to this, it is possible to assemble the supply valve, the urging member and the seal member to the liquid supplying part easily without using the fixture to stop the supply valve temporarily. 
   In the method for manufacturing a liquid cartridge, the urging member insertion step may comprise a step of inserting a coil spring as the urging member into the hollow part from the liquid supplying opening, and the supply valve insertion step may insert the supply valve into the hollow part against an urging force of the coil spring by engaging the supply valve with the coil spring. 
   Due to this, it is possible to engage the coil spring and the supply valve securely, even after the supply valve is fitted into the hollow part of the liquid supplying part. 
   In the method for manufacturing a liquid cartridge, during the seal member mounting step, the seal member may be mounted in the liquid supplying opening of the liquid supplying part where the urging member is inserted in the urging member insertion step. 
   Due to this, it is possible to mount the urging member and the seal member on the liquid supplying part further easily, because the urging member is inserted before the seal member is mounted on the liquid supplying part. 
   According to the second aspect of the present invention, a liquid cartridge comprises a liquid accommodating chamber for containing a liquid, a hollow part having a liquid supplying opening, into which a liquid supplying needle of a liquid ejecting apparatus is inserted, while the liquid supplying opening communicating with the liquid accommodating chamber, a seal member contained in the hollow part, the seal member having an insertion opening being in elastic contact with an external circumference of the liquid supplying needle, while the liquid supplying needle is inserted to the insertion opening, a supply valve contained in the hollow part, the supply valve arranged in order to close or open the insertion opening of the seal member and an urging member for urging the supply valve toward the seal member, wherein the supply valve comprises a body part having a circular cross-section, of which a diameter is substantially the same as a diameter of the hollow part of the liquid supplying part, and having a cylindrical shape, of which a height is higher than the diameter of the hollow part of the liquid supplying part, a taper part formed at a first end of the body part, the taper part having an end engaged with the urging member and a bottom face formed at a second end of the body part, the bottom face having a flat surface being in contact with the seal member. 
   Due to this, since the height of the body part of the supply valve is larger than the diameter of the hollow part of the liquid supplying part, the supply valve does not turn on the surface parallel to the sliding direction of the supply valve at the time of assembly and when the liquid supplying needle is in contact with the supply valve, and it can slide along the hollow part of the liquid supplying part securely. In addition, since the supply valve has the taper part, it is possible to insert the supply valve into the liquid supplying part from the insertion opening of the seal member even after the seal member is fitted into the liquid supplying part. Further, since the supply valve has the flat bottom face, it can move in the sliding direction securely when the liquid supplying needle is in contact with the supply valve. 
   In the liquid cartridge, the urging member may be a coil spring, and a distance between the taper part engaged with the first end of the coil spring in the hollow part of the liquid supplying part and a spring seat for preventing the second end of the coil spring from moving in the hollow part may be longer than the height of the body part of the supply valve, when the bottom face of the supply valve is in contact with the seal member. 
   Due to this, since the space where the coil spring is provided is long enough, it is possible to use a coil spring of which the wire diameter is large and the urging force is strong. Therefore, it is possible to urge the supply valve to the seal member by the coil spring with a strong force. 
   A diameter of the body part of the supply valve may be larger than a diameter of the liquid supplying needle inserted from the liquid supplying opening to allow the supply valve to slide in the hollow part. 
   Due to this, since the diameter of the seal member is smaller than the diameter of the liquid supplying part, the supply valve having the body part of which the diameter is larger than the liquid supply needle can seal the insertion opening of the seal member securely. 
   The supply valve may have a concave part for accepting the coil spring to urge the supply valve. 
   Due to this, since the coil spring is provided to the concave part of the supply valve, the urging force of the coil spring is transferred to the supply valve securely. Therefore, the supply valve can seal the insertion opening of the seal member securely. Further, since the concave part is provided in the supply valve for the liquid cartridge, it is possible to prevent the sink at the bottom face of the supply valve when the supply valve for the liquid cartridge is formed by injection molding. 
   The summary of the invention does not necessarily describe all necessary features of the present invention. The present invention may also be a sub-combination of the features described above. The above and other features and advantages of the present invention will become more apparent from the following description of the embodiments taken in conjunction with the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a front perspective view of an ink cartridge  100  according to a first embodiment. 
       FIG. 2  is a rear perspective view of an ink cartridge  100  before a film  110  is attached. 
       FIG. 3  is a rear perspective view of an ink cartridge  100  after a film  110  is attached. 
       FIG. 4  is an exploded perspective view of an ink cartridge  100 . 
       FIG. 5  is an exploded perspective view of an ink cartridge  100 . 
       FIG. 6  is a front view of an ink cartridge  100  in a state before a film  130  is attached. 
       FIG. 7  is a front view of an ink cartridge  100  in a state after a film  130  is attached. 
       FIG. 8  is a rear view of an ink cartridge  100  in a state before a film  110  is attached. 
       FIG. 9  is a cross-section view of an ink cartridge  100 . 
       FIG. 10  is an exploded perspective view of an ink supply section  160 . 
       FIG. 11  shows another embodiment of a supply valve. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   The invention will now be described based on the preferred embodiments, which do not intend to limit the scope of the present invention, but exemplify the invention. All of the features and the combinations thereof described in the embodiment are not necessarily essential to the invention. 
     FIG. 1  is a front perspective view of the structure of the ink cartridge  100  used for an inkjet type recording apparatus, which is adapted for an example of a liquid cartridge suitable for supplying a liquid to a liquid ejecting head of a liquid ejecting apparatus, obliquely viewed from an upper position. 
   In addition, the liquid ejecting apparatus of the present invention is not limited to the liquid ejecting head of the liquid ejecting apparatus, and it includes a color material ejecting head of the color filter manufacturing apparatus for manufacturing color filters of a liquid crystal display, an electrode material (conduction paste) ejecting head for forming electrodes such as an organic EL display or a FED (Field Emission Display) and further a bio organism ejecting head of the biochip manufacturing apparatus and a sample ejecting head as a minute pipette for manufacturing biochips. 
     FIG. 2  and  FIG. 3  are rear perspective views the ink cartridge  100  in  FIG. 1  obliquely viewed from a lower position,  FIG. 2  shows the ink cartridge  100  in a state a film  110  is not attached thereto and  FIG. 3  shows the ink cartridge  100  in a state the film  110  is attached thereto. Further,  FIG. 4  and  FIG. 5  are perspective views showing the ink cartridge  100  wherein members of which the ink cartridge  100  consist is exploded.  FIG. 6  and  FIG. 7  are front views of the ink cartridge  100  in  FIG. 1 ,  FIG. 6  shows the ink cartridge  100  in a state before a film  130  is attached to an opening part  122  of the ink cartridge  100  and  FIG. 7  shows the ink cartridge  100  in a state in which a film  130  is attached to an opening part  122  of the ink cartridge  100 . In addition, the film  130  is attached to an area, which is shown with hatching in  FIG. 7 . 
   As shown in  FIG. 4 , the ink cartridge  100  has a cartridge body  120  having a shape of an approximate case with the opening part  122 , the film  130 , which covers almost all face of the opening part  122  and a lid  140 , which covers the outside of the film  130 . The internal part of the cartridge body  120  is partitioned by ribs or walls as described below. The film  130  seals almost all face of the opening part  122  of the cartridge body  120  in order that the internal part of it comes into a closed state. The lid  140  is further fixed to the cartridge body  120  in order to wrap the outside of the film  130  in a non-closed state. 
   The cartridge body  120  has an ink accommodating chamber  111  for containing ink, an ink channel part from the ink accommodating chamber  111  to an ink supply section  160 , an ink side passage, which allows the ink accommodating chamber  111  to communicate with the atmosphere, the atmospheric valve accommodating section and an atmosphere communicating part, which consists of an atmosphere passage, and it is made of, for example, Polypropylene (PP) in a unified body. 
   The ink cartridge  100  further has an ink supply controlling means  150 , a memory  170  and an engaging lever  180 . The ink supply section  160  supplies ink, which is contained in the ink accommodating chamber  111 , to the recording head of the inkjet type recording apparatus through an ink supply needle of the apparatus which needle is inserted into an opening of the ink supplying section  160 . The ink supply needle faces the lower face of the cartridge body  120  and is formed on the carriage  42  mounting thereon the ink cartridge  100 . The memory  170  is caulked into an attaching part  190  and the attaching part is caulked and attached to the lower part of the side face of the cartridge body  120 . The memory  170  stores the information on the kind of the ink cartridge  100 , the information on the color held by the ink cartridge  100  and the information on the present amount of remaining ink etc., and it transfers this information by a plurality of terminals  171 , which are exposed thereon, between the apparatus body and the ink cartridge  100 . The engaging lever  180  is formed at the upper part of the side face opposite to the attaching part  190  in regard to the cartridge body  120 , and is engaged with the carriage of the inkjet type recording apparatus. 
   An ink supply controlling means  150  consists of a differential pressure valve, which supplies ink of the ink accommodating chamber  111  to the ink supply section  160  by pressure difference between ink accommodating chamber  111  and the ink supply section  160  that occurs accompanying the consummation of ink. The ink supply controlling means has a membrane valve  900 , which is an example of a valve member inserted into a concave part  495  of the cartridge body  120 , capable of elastic deformation, a valve lid  151  which covers the concave part  495 , a coil spring  907  which is an example of an urging member arranged between the membrane valve  900  and the valve lid  151 . 
   The ink accommodating chamber  111  is divided by a wall  272  mainly into a upper part and a lower part, which extends in a horizontal direction, as shown in  FIG. 6  and  FIG. 7 , and an atmospheric side accommodating chamber  270 , which can communicate with the ambient air by a communicating hole  242 , is formed in the lower part, while a liquid-supply side accommodating chamber, which consists of a first ink accommodating chamber  292  and a second ink accommodating chamber  294  and is blocked from the atmosphere, is formed in the upper part. The liquid-supply side accommodating chamber  290  is divided by a slope wall  271  having a communicating part  276  near the wall  272  (at the lower part area) into the first and second ink accommodating chambers  292  and  294 , and is provided with a channel part  296 , which is arranged in order to surround the circumference of the second ink accommodating chamber  294 . The channel part  296  is coupled with the second ink accommodating chamber  294  via a communicating part  278  at the lower part, and besides is coupled with the ink supply controlling means  150  via passages  298  and  300  and a passage hole  918 . 
   Moreover, the lower flow side of the ink supply controlling means  150  is configured to communicate with the ink supply section  160  via a passage hole  910  which communicates with the ink supply controlling means  150 , a communicating part  302  and a channel  321  which communicate with the passage hole  910 , a passage hole  323  which is formed at an end of the channel  321  and is formed to face the front face side and a communicating part  304  of which an end communicates with the passage hole  323 . 
   The atmospheric side accommodating chamber  270  and the first ink accommodating chamber  292  communicate with each other by a communicating passage  295  which extends vertically, and are configured in order that the ink in the atmospheric side accommodating chamber  270  is sucked up into the first ink accommodating chamber  292  corresponding to the consummation of ink from the ink supply section  160  and then is flowed into the ink supply controlling means  150  via the second ink accommodating chamber  294  and the channel part  296  etc. The ink is flowed into the ink supply controlling means  150  from the atmospheric side accommodating chamber  270  of the ink accommodating chamber  111  through a sequence of the communicating part  274 , a second ink injection hole  162 , a communicating passage  295 , the communicating parts  276  and  278 , the channel part  296 , the passages  298  and  300  and the passage hole  918 . 
   Meanwhile, the atmospheric valve part  250  has an atmospheric valve accommodating section  232 , which is hollow therein, for containing an atmospheric valve  254 , and has a communicating hole  239 , also serving as a atmosphere communicating channel, of which the diameter is a little larger than that of a shaft part  264  of the atmospheric valve  254 , on the wall face of a lower position of the atmospheric valve accommodating section  232 , so that the shaft part  264  of the atmospheric valve  254  is always urged towards the bottom face of the ink cartridge  100  by a spring  255  and inserted thereto to be able to freely slide, and the communicating hole  239  is sealed by the atmospheric valve  254  when the ink cartridge  100  is not mounted onto the carriage of the inkjet type recording apparatus. Owing to this, the atmospheric valve  254  is arranged to be capable of moving in a vertical direction in which the ink cartridge  100  is mounted on the carriage, and opens the communicating hole  239  by being pressed upward by a contact member  60  as an example of a contact member formed in carriage when mounted on the carriage. 
     FIG. 8  is a rear view showing the ink cartridge  100  of  FIG. 1  in a state before the film  110  is attached thereto. The atmosphere side passage, which communicates with the atmosphere taking the communicating hole  239  described above as a boundary, consists of an opening  212 , a passage  214  which is circuitous or winding, a filter accommodating section  216 , a communicating hole  218 , a communicating part  222  and a communicating hole  253  and a communicating part  224  which are formed on the bottom face of the communicating part  222 . 
   Particularly, as shown in  FIG. 8 , an end of one circuitous passage  214 , which is formed on the front face of the cartridge body  120  and winding in the shape of a maze, is opened with the atmosphere by the opening  212 , and the other end is coupled with the filter accommodating section  216  for containing the filter  215  ( FIG. 4  and  FIG. 5 ) having a function of ink repellency and air permeability. The filter container part  216  communicates with the communicating hole  218 , which penetrates from the front side to the rear side of the cartridge body  120 . The communicating hole  218  is coupled with the communicating part  224  via the communicating part  222  and the communicating hole  253 , which is formed on the bottom part of a room that partitions the communicating part  222 , in the rear side of the cartridge body  120 . In the middle of the passage  214 , a chamber  930 , which consists of a concave part, is provided. 
   As shown in  FIG. 2 , the communicating part  224  is formed as a concave part  257  on the bottom face of the cartridge body  120 , and a shaft part  264 , which is an operating rod of the atmospheric valve  254 , is exposed, while the communicating hole  239  capable of communicating with the atmospheric valve accommodating section  232 , which contains the atmospheric valve  254 , and the communicating hole  253 , which communicates with the communicating part  222 , are formed inside the concave part  257 , and the external face of the concave part  257  is sealed by the film  132  for sealing the first and second ink injection holes  161  and  162 . A material, which can perform elastic deformation by a pressing force of a projection protruding from the carriage, is chosen for this film  132 . 
   Meanwhile, as shown in  FIG. 6 , the ink side passage, which communicates with the atmospheric side accommodating chamber  270  taking the communicating hole  239  described above as a boundary, consists of an atmospheric valve accommodating section  232 , a passage hole  234   a , a communicating chamber  234   b , a communicating part  234   c , a communicating chamber  234   d , a communicating part  236 , a communicating chamber  237  and a communicating hole  238 , a communicating groove  240  and a communicating hole  242 . Particularly, the passage hole  234   a  is formed on a wall of upper part of the atmospheric valve accommodating section  232 , and the atmosphere passage is formed to communicate in the following sequence: the communicating chamber  234   b  via the passage hole  234   a , the communicating part  234   c  formed by a notch on a wall of the upper part of the communicating chamber  234   b , the communicating chamber  234   d  provided at the upper part of the communicating part  234   c , the communicating part  236  formed by a notch of a wall of the upper part of the communicating chamber  234   d  and the communicating chamber  237  provided with the communicating hole  238  at a lower position. 
   The communicating hole  238 , which penetrates from the rear side to front side of the cartridge body  120 , communicates with the atmospheric side accommodating chamber  270  via the communicating groove  240 , which communicates with the communicating hole  238 , and the communicating hole  242 , which communicates with the communicating groove  240  and also penetrates from the front side to the rear side of the cartridge body  120 . 
   These the atmospheric side accommodating chamber  270 , the liquid-supply side accommodating chamber  290 , the atmospheric valve part  250  and the atmosphere side passage and the ink side passage become an area which is separated from the atmosphere by attaching the films  130  and  110  to the wall partitioning each of those by thermo welding or fuse bonding. 
   The ink supply section  160  has a seal member  12 , which is made of elastomer having an insertion opening  26  into which the ink supply needle provided in the carriage is inserted, a supply valve  13 , which closes the insertion opening  26  of the seal member  12  and an urging member, which consists of a coil spring etc. that urges the supply valve  13  towards the seal member  12 . In addition, a film  604  is attached to the insertion opening  26  of the seal member  12  at the time of factory. 
   When the ink cartridge  100  is mounted on the carriage of the inkjet type recording apparatus, the projecting part provided in the carriage pushes up the shaft part  264  of the atmospheric valve upwardly via the film  132  and the ink supply needle of the carriage pushes up the supply valve  13  of the ink supply section  160  upwardly. Due to this, the communicating hole  239  allows the atmosphere channel, extending the atmospheric valve accommodating section  232  to the communicating hole  242 , to communicate with the atmosphere. And, the upper flow than the supply valve  13  in regard to the ink supply section  160  communicates with the ink supply needle. 
   When the inkjet type recording apparatus begins to record in a state where the communicating hole  242  communicates with the ambient air, the recording head is supplied with ink through the ink supply needle from the ink supply section  160 . When ink is supplied from the ink supply section  160 , the ink, which is flowed in a sequence of an arrow a shown in  FIG. 6  and the passage hole  918  in the ink accommodating chamber  111 , is flowed in a sequence of arrows b, c and d shown in  FIG. 6  via the ink supply controlling means  150 , is flowed into the ink supply section  160  and is supplied to the ink supply needle inserted in the ink supply section  160 . 
   According to this flow of ink, in the ink accommodating chamber  111 , the ink of the atmospheric side accommodating chamber  270  is supplied to the liquid-supply side accommodating chamber  290 . The atmosphere accompanying the consummation of ink in the atmospheric side accommodating chamber  270  is flowed into the atmospheric side accommodating chamber  270  from the communicating hole  242  through a route in a sequence of an arrow f in  FIG. 6 , the communicating part  224  of the bottom face and an arrow g. Although the liquid level of the atmospheric side accommodating chamber  270  goes down because ink is provided to the recording head from the ink supply section  160 , the channel, which is coupled with the atmospheric side accommodating chamber  270  and the liquid-supply side accommodating chamber  290 , is provided with a communicating opening at the lowest part of the atmospheric side accommodating chamber  270 , so that the atmosphere is not flowed into the liquid-supply side accommodating chamber  290  until all of the ink in the atmospheric side accommodating chamber  270  is moved to the liquid-supply side accommodating chamber. 
   After the ink in the atmospheric side accommodating chamber  270  is completely consumed, the ink in the first and second ink accommodating chambers  292  and  294  of the liquid-supply side accommodating chamber  290  is consumed in that sequence. During that time, due to the surface tension caused by the meniscus of ink formed in the second ink injection hole  162 , which communicates with the liquid-supply side accommodating chamber  290  and the atmospheric side accommodating chamber  270 , the ink in the liquid-supply side accommodating chamber  290  is prevented from being flowed backward to the atmospheric side accommodating chamber  270 . 
   When the ink in the first ink accommodating chamber  292  begins to be consumed, the air is flowed into the first ink accommodating chamber  292 . Due to this, the liquid level of the first ink accommodating chamber  292  goes down, but the first and second ink accommodating chambers  292  and  294  communicate by the communicating part  276  only at the lower part, so that the ink in the first ink accommodating chamber  292  is first consumed. When the liquid level reaches the communicating part  276  because the ink in the first ink accommodating chamber  292  is consumed, the air is flowed into the second ink accommodating chamber  294  according to the consummation of ink in the second ink accommodating chamber  294 . While the ink in the second ink accommodating chamber is consumed, the surface tension caused by the meniscus of ink in the communicating part  276  occurs, and therefore the ink in the second ink accommodating chamber  294  is prevented from being flowed backward to the first ink accommodating chamber  292 . 
   As described above, although the ink in the atmospheric side accommodating chamber  270  and the first and second ink accommodating chambers  292  and  294  is consumed in that sequence, the ink is supplied into the ink supply section  160  through the passage hole  918  via the passage  300  from the communicating part  278 , which is provided near the wall  272  that partitions the ink accommodating chamber into nearly two parts up and down, even though the liquid level of ink exists in any accommodating section. 
     FIG. 9  is a cross-section view that shows an A—A section in regard to the ink cartridge  100  in  FIG. 6 . The ink supply section  160  is provided with a hollow part  34  having an ink supplying hole  32  at a bottom face. The ink supplying hole  32  is formed at a lower face side of the ink cartridge  100 , and the ink supply needle  36  of the inkjet type recording apparatus is inserted. The hollow part  34  is a hollow cylinder in shape, and has a passage  35  in the shape of a groove provided on the external side of the cylinder along the longitudinal direction of the cylinder. In the hollow part  34  of the ink supply section  160 , an the urging member  14 , a supply valve  13  and a seal member  12  are provided to face from the ink supply controlling means  150  to the ink supplying hole  32  in that sequence. In the embodiment shown in  FIG. 9 , the urging member  14  is a coil spring. The seal member  12  is made of an elastic material such as elastomer. An insertion opening  26  elastically arranged at an external circumference of the ink supply needle  36  is provided in the seal member  12 , while the ink supply needle  36  is inserted. One end of the urging member  14  is in contact with a spring seat  38  in the hollow part  34 , and the other end is engaged with the supply valve  13  to urge the supply valve  13  toward the seal member  12 . The spring seat  38  controls the urging member  14  in the hollow part  34  so that the position of an end of the urging member  14  is not moved. 
   When the ink supply needle  36  is inserted into the insertion opening  26  of the seal member  12  and pushes up the supply valve  13 , the supply valve  13  slides upwardly along a sliding direction B in the hollow part  34  and is separated from the insertion opening  26  of the seal member  12 . Consequently, it is possible to position a passage hole of the ink supply needle  36  not shown to the hollow part  34  side rather than a position where the seal member  12  and the supply valve  13  are in contact with each other, and thus the hollow part  34  and the passage hole of the ink supply needle  36  communicate with each other so that the recording head communicating with the ink supply needle  36  can be ready to be supplied with ink. 
   Meanwhile, when the ink supply needle  36  is pulled out from the insertion opening  26  of the seal member  12 , the supply valve  13  slides downwardly along the sliding direction in the hollow part  34  by the elastic force of the urging member  14 , and seals the insertion opening  26  of the seal member  12 . 
   The supply valve  13  has a body part  500 , a taper part  510 , a bottom face  520  and concave part  530 , and is formed by injection molding of, e.g., Polypropylene. The supply valve  13  is contained in the hollow part  34 , and is placed so as to open the insertion opening  26  of the seal member  12 . The body part  500  of the supply valve  13  is a nearly cylinder in shape, and the outer diameter of the body part  500  is substantially the same as the diameter of the hollow part  34 . In addition, the height of the body part  500  in the sliding direction is larger than the diameter of the hollow part  34 . Therefore, when the ink supply needle  36  is in contact with the supply valve  13 , the supply valve  13  does not deviate from the sliding direction of the supply valve  13 , and can slides along the sliding direction B smoothly. In addition, a part of the body part  500  in the shape of a cylinder is flat, but this is a position of a gate in case the supply valve  13  is formed by injection molding. The taper part  510  is tapered at an upper end of the body part  500  in the state of being contained in the hollow part  34 . The bottom face  520  is formed at a lower end of the body part  500  in the state of being contained in the hollow part  34 , and all the face is a flat surface. Due to this, the ink supply needle  36  is pressed to the flat surface of the bottom face  520  of the supply valve  13 , so that the supply valve  13  can be moved along the sliding direction B securely. In the supply valve  13 , a concave part  530  is provided from the taper part  510  to an intermediate level inside the body part  500  toward the bottom face  520 . Due to this, it is possible to prevent the sink from occurring when forming the supply valve  13  by injection molding and to form the bottom face  520  in the shape of a flat surface. 
   As shown in  FIG. 9 , the distance L 1  from the spring seat  38  to the end of the supply valve  13  in the state where the ink supply needle  36  is not inserted into the insertion opening  26  of the seal member  12  is longer than the length L 2  of the body part  500  in the sliding direction B. Therefore, it is possible to use the coil spring of which the urging force is strong by making the wire diameter of the urging member  14  big. Since the supply valve  13  is pressed by a strong force of the coil spring to the insertion opening  26  of the seal member  12 , it is possible to seal the insertion opening  26  of the seal member  12  securely. 
   As shown in  FIG. 9 , an inner diameter D 1  of the insertion opening  26  of the seal member  12  is smaller than an outer diameter D 2  of the body part  500  of the supply valve  13  and an outer diameter D 3  of the ink supply needle  36 . Since the inner diameter D 1  of the insertion opening  26  of the seal member  12  is smaller than the outer diameter D 3  of the ink supply needle  36 , the seal member  12  seals between the ink supply needle  36  and the insertion opening  26  securely by elastic deformation when the ink supply needle  36  is inserted into the insertion opening  26 . In addition, the outer diameter D 2  of the body part  500  of the supply valve  13  is larger than the outer diameter D 3  of the ink supply needle  36 . Therefore, even when the ink supply needle  36  is pulled out from the insertion opening  26  of the seal member  12 , the supply valve  13  is not fallen off from the ink supply needle  36  and the insertion opening, and it is possible to seal the insertion opening  26  securely. Further, since the supply valve  13  can be configured to have a small size and a simple shape, it is possible to shorten the distance between the ink supply controlling means  150  and the supply valve  13  in contrast to the prior art. Therefore, it is possible to increase the capacity of ink in comparison to the conventional ink cartridge. 
     FIG. 10  is an exploded perspective view of the ink supply section  160 . In assembling the ink supply section  160 , the urging member  14  is first inserted into the hollow part  34  from the ink supplying hole  32  of the ink supply section  160 . Then, the seal member  12  is fitted into the ink supplying hole  32  of the ink supply section  160  in which the urging member  14  has been inserted. Moreover, it is preferable that the outer diameter of the coil spring of the urging member  14  is larger than the inner diameter D 1  of the insertion opening  26  of the seal member  12 . Due to this, it is possible to prevent the coil spring of the urging member  14  bouncing out from the insertion opening  26 . Next, the supply valve  13  is pushed into the insertion opening  26  the seal member  12  fitted into the ink supplying hole  32 , and is inserted into the hollow part  34  against the urging force of the urging member  14 . Since the supply valve  13  has the taper part  510  at its end, it is inserted into the ink supply section  160  through the insertion opening  26  of which the diameter is smaller than the body part  500  even after the seal member  12  is fitted into the ink supplying hole  32 . And, the end of the taper part  510  enters the inside of the coil spring of the urging member  14 , and the supply valve  13  and the urging member  14  is engaged with each other securely. In addition, the urging member  14  may be inserted into the hollow part  34  from the insertion opening  26  of the seal member  12  after the seal member  12  is fitted into the ink supplying hole  32 , or further the supply valve  13  may be inserted into the hollow part  34  from the insertion opening  26 . 
   When the supply valve  13  is inserted into the hollow part  34 , it is in contact with the seal member  12  by the urging force of the urging member  14 . Since the supply valve  13  is inserted into the ink supplying hole  32  where the urging member  14  and the seal member  12  are already assembled, it is possible to perform the engagement of the supply valve  13  and the urging member  14  and the insertion of the supply valve  13  into the hollow part  34  at the same time. Therefore, it is possible to assemble the ink supply section  160  easily. Due to this, it is possible to reduce the man-hour of assembling the ink supply section  160  and to decrease the production cost of the ink cartridge  100 . 
   Further, according to the present embodiment, unlike the conventional method of assembling the seal member in the state the urging part and the supply valve is fitted in advance, it is not necessary to insert the fixture from the side face of the cartridge and stop the supply valve temporarily against the urging force of the urging member. Therefore, it is unnecessary to provide a hole for inserting the fixture for stopping the supply valve temporarily in the ink cartridge  100 . In addition, the cost of making the fixture is not needed, so that the production cost of the ink cartridge  100  is further reduced. 
     FIG. 11  shows another embodiment of the supply valve  13 . A concave part  530  of a supply valve  13  is provided along the center axis of a body part  500  in the shape of a cylinder from an end part where a taper part  510  of the body part  500 . An inner diameter of the concave part  530  is substantially the same as an outer diameter of a coil spring, an example of the urging member  14 . One end of the urging member  14  is inserted into the concave part  530 . Further, at an end part of the concave part  530 , an internal-side taper part is provided to have an inclined cross-section so that the inner diameter becomes small gradually from the end of the concave part  530  inwardly. 
   Since one end of the urging member  14  is held in the middle of the concave part  530  of the supply valve  13 , the urging force of the urging member  14  is transferred to the supply valve  13  securely. The supply valve  13  can seal the insertion opening  26  of the seal member  12  securely. In addition, since the concave part  530  has the internal-side taper part, although the inner diameter of the concave part  530  and the outer diameter of the urging member  14  are substantially the same, it is possible to insert the urging member  14  into the concave part  530  easily when assembling the ink supply section  160 . 
   As described above, according to the present invention, it is possible to assemble the ink supply section  160  easily in comparison to the prior art. Therefore, it is possible to reduce the production time of the ink cartridge  100  and to decrease the production cost of the ink cartridge  100 . 
   Although the present invention has been described by way of exemplary embodiments, it should be understood that those skilled in the art might make many changes and substitutions without departing from the spirit and the scope of the present invention which is defined only by the appended claims.