Patent Document

CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application claims priority from Japanese Patent Application No. JP-2006-099835, which was filed on Mar. 31, 2006, and U.S. Provisional Patent Application No. 60/826,254, which was filed on Sep. 20, 2006, the disclosures of which are incorporated herein by reference in their entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates generally to ink cartridges. In particular, the present invention is directed towards ink cartridges which may be used in combination with printers. 
         [0004]    2. Description of Related Art 
         [0005]    A known printer performs printing by ejecting ink from a nozzle toward a recording sheet. Such a known printer is configured to be used in combination with a removable ink cartridge. The ink cartridge used with this known printer comprises an ink supply hole for supplying ink within an ink chamber to a printer head, which is formed on a lower side of a side wall when the ink cartridge is installed in the printer. 
         [0006]    Nevertheless, if the ink jet head attempts to eject ink when there is substantially no ink within the ink chamber, printing is not performed, and air may be drawn into the ink jet head. When air is drawn into the ink jet head, the ink jet head may be damaged, such that the ink jet head may become unusable. Consequently, it is desirable to monitor how much ink is within the ink chamber, and when there is substantially no ink within the ink chamber, to prohibit the attempted ejecting of ink from the ink jet head. 
         [0007]    Another known ink cartridge is configured to monitor the ink within the ink chamber. This known ink cartridge comprises a rotating member which is supported by a support member provided on a bottom wall of the ink chamber, such that the rotating member is configured to rotate when the ink cartridge is attached to the printer. A blocking portion is provided on one end of the rotating member, and a float portion is provided on the other end of the rotating member. Consequently, as the surface level of the ink drops due to a decrease in ink within the ink chamber, the position of the float portion along a vertical direction also drops, and the position of the blocking portion along a vertical direction rises, thereby allowing detection of ink depletion. 
       SUMMARY OF THE INVENTION 
       [0008]    A need has arisen for ink cartridges that overcome shortcomings of the related art. 
         [0009]    According to an embodiment of the present invention, an ink cartridge comprises a case, and the case comprises a first case member. The first case member comprises a first wall, and the first wall comprises a translucent portion extending from the first wall in a predetermined direction. The translucent portion has an inner space formed therein. The case also comprises a second case member connected to the first case member. The first case member and the second case member define an ink chamber therein, and the second case member comprises a second wall which is opposite to the first wall, and a support member connected to an interior surface of the second wall. Moreover, the ink cartridge comprises a movable member which comprises a signal blocking portion. The signal blocking portion is positioned within the inner space of the translucent portion, and the movable member is connected to the support member. 
         [0010]    According to another embodiment of the present invention, an ink cartridge comprises a case, and the case comprises a first case member comprising a first wall. The first wall comprises an ink supply portion or an air intake portion, or both, extending from the first wall in a predetermined direction. The case also comprises a second case member connected to the first case member, and the first case member and the second case member define an ink chamber therein. The second case member comprises a second wall which is opposite to the first wall, and a support member connected to an interior surface of the second wall. Moreover, the ink cartridge comprises a movable member, and the movable member is connected to the support member. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    For a more complete understanding of the present invention, the needs satisfied thereby, and the features and technical advantages thereof, reference now is made to the following descriptions taken in connection with the accompanying drawings. 
           [0012]      FIG. 1  is an oblique view of an ink cartridge having an ink chamber, according to an embodiment of the present invention. 
           [0013]      FIG. 2  is a partial, disassembled view of the ink cartridge of  FIG. 1 . 
           [0014]      FIG. 3  is a cross-sectional view of a body and a lid of the ink cartridge of  FIG. 1 . 
           [0015]      FIG. 4  is a side view showing a side wall in which an ink supply portion and an air-introduction portion of the ink chamber of  FIG. 1  are provided. 
           [0016]      FIG. 5  is a drawing depicting a method for installing the ink cartridge of  FIG. 1  into a printer. 
           [0017]      FIG. 6  is a drawing depicting a motion of a movable member of the ink cartridge of  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       [0018]    Embodiments of the present invention and their features and technical advantages may be understood by referring to  FIGS. 1-6 , like numerals being used for like corresponding portions in the various drawings. 
         [0019]    Referring to  FIG. 1 , an ink cartridge  1  may have a body comprising a plurality of surfaces, e.g., six surfaces. For example, the plurality of surfaces may comprise a pair of substantially rectangular surfaces which have the largest surface area of the plurality of surfaces, and four (4) side surfaces connected to the pair of substantially rectangular surfaces. As described hereinafter, the direction along the long perimeter of the pair of substantially rectangular surfaces is designated as the lengthwise direction, the direction along the short perimeter of the pair of substantially rectangular surfaces is designated as the short direction, and the direction connected to the pair of substantially rectangular surfaces is designated as the width direction. The pair of substantially rectangular surfaces also are designated as the front surface and the back surface, respectively. 
         [0020]    Ink cartridge  1  may have a bottomed box-shaped body  10  having a main opening  11 , and a lid  50  configured to close main opening  11  of body  10 , and lid  50  and body  11  may comprise a case of ink cartridge  1 . Ink cartridge  1  may comprise an ink chamber  60  which is configured to store ink and is defined by lid  50  and body  11 , and a movable member  70  which may be supported, in such a manner that it may be configured to rotate based on a change in the amount of ink within ink chamber  60 . Ink chamber  60  and movable member  70  may comprise a resin material, e.g., polypropylene, and are manufactured using injection molding. Body  10  of ink chamber  60  may have a light-transmitting property, and movable member  70  may have a light-obscuring property. Additionally, an ink supply portion  120  may be provided in ink cartridge  1 , which may supply ink stored in ink chamber  60  from an interior of ink chamber  60  to an exterior of ink chamber  60 , and an air-introducing portion  130  which introduces air into ink chamber  60 . 
         [0021]    Ink cartridge  1  may be installed in printer  1000 , such that the surfaces comprising the largest surface area are vertical, and the lengthwise direction of the surfaces forming the largest surface area is along a horizontal direction. At such time, an ink supply portion  120  and an air-introducing portion  130  may be positioned on a side surface, with ink supply portion  120  positioned on the bottom side, and air-introducing portion  130  positioned on the top side. 
         [0022]    Referring to  FIGS. 2 and 3 , on the bottom side of the wall confronting main opening  11  of body  10 , an ink supply path  20  may be provided, which communicates with ink chamber  60 , and on the top side an air-communicating path  30  may be provided, which communicates with ink chamber  60 . In this embodiment of the present invention, the direction facing the inside of reservoir  60  from the wall confronting main opening  11  of body  10  is designated as the “inside direction,” and the direction facing the outside of ink chamber  60  is designated as the “outside direction.” 
         [0023]    Ink supply path  20  and air-communicating path  30  each may have a cylindrical shape extending along the lengthwise direction. One end of ink supply path  20  and air-communicating path  30  may project in the inside direction, and the other end may project in the outside direction. A portion of an ink supply mechanism  80  may be inserted into ink supply path  20  to form an ink supply portion  120 . Similarly, a portion of an air-introducing mechanism  90  may be inserted into air-communicating path  30  to form an air-introducing portion  130 . 
         [0024]    When ink cartridge  1  is not installed in printer  1000 , supply mechanism  80  closes the ink flow path, and when ink cartridge  1  is installed in printer  1000 , and an ink extraction tube  1015  of printer  1000  is inserted, the ink flow path opens. Consequently, when ink cartridge  1  is installed in printer  1000 , ink supply portion  120  is able to supply ink from ink chamber  110  to printer  1000 . 
         [0025]    Air-introducing mechanism  90  may comprise a rod-shaped valve-opening portion  30   a  which projects toward the outside of air-communicating path  30  when a portion of air-introducing mechanism  90  is placed within air-communicating path  30 . When an ink cartridge  1  is not installed in printer  1000 , air-introducing mechanism  90  closes off the air flow path, and when an ink cartridge  1  is installed in printer  1000 , valve-opening portion  30   a  contacts an installation surface  1013  of printer  1000 , and when pressure is applied toward the inside of air-communicating path  30 , the air flow path opens. Consequently, when an ink cartridge  1  is installed in printer  1000 , air-introducing portion  130  draws air into communication with the inside of ink chamber  60 . 
         [0026]    Referring to  FIG. 4 , the length along the width direction of ink supply portion  120  and air-introducing portion  130  may be substantially the same as the length D 1  along the width direction of ink cartridge  1 . Referring again to  FIGS. 2 and 3 , a translucent portion  40  may project to the outside direction and may provided between ink supply path  20  and air-communicating path  30  on the wall of body  10  on which ink supply path  20  and air-communicating path  30  are provided. Referring to  FIG. 4 , the length D 2  of translucent portion  40  along the width direction may be shorter than the length D 1  of ink cartridge  1  along the width direction. A space may be formed inside translucent portion  40 , which may communicate with ink chamber  60  and may extend vertically. Referring to  FIG. 1 , one end of a movable member  70  supported within ink chamber  60  may be disposed within translucent portion  40  and may change its position vertically within the space within translucent portion  40 . Moreover, a contact member  40   a  may be provided at the bottom end of the space within translucent portion  40 , which contacts movable member  70  when one end of movable member  70  changes its position downward. 
         [0027]    Referring to  FIG. 5(   b ), when an ink cartridge  1  is installed in printer  1000 , translucent portion  40  positioned between a light-emitting portion  1014   a  and a light-receiving portion  1014   b  of a sensor  1014 , e.g., an optical sensor, provided in printer  1000 . 
         [0028]    A pair of support members  51  may project from a lid  50 , which support movable member  70 , and when main opening  11  of body  10  is covered by lid  50 , a pair of contact members  53  may contact a corresponding one of a pair of mutually confronting inner wall surfaces which form the largest surface area of body  10 . Support members  51  may be formed integral with lid  50 . Referring to  FIG. 4 , support members  51  may be provided adjacent to the ends of lid  50  in the width direction, but may be positioned more to the inside than the ends of lid  50  in the width direction, such that support members  51  may form a line along the width direction. 
         [0029]    An arm-supporting portion  52  may be formed on support members  51 , which supports a shaft  77  of movable member  70 , in such a manner that movable member  70  may move in a rotating motion. Arm supporting portion  52  may be a U-shaped cutout as seen from the vertical direction of a paper in  FIGS. 2 and 3 . 
         [0030]    Referring to  FIG. 1 , movable member  70  may be a substantially rod-shaped member comprising a material with a lower specific gravity than the specific gravity of ink. One end of movable member  70  forms blocking portion  71  disposed within translucent portion  40 , and the other end of movable member  40  forms float portion  73 . Blocking portion  71  and float portion  73  may be connected via a connecting portion  75 . 
         [0031]    Connecting portion  75  may have an attachment axis  77  which extends along the width direction of ink cartridge  1 . Each proximal end of attachment axis  77  may be supported by a corresponding one of a pair of arm support portions  52  formed in a pair of support members  51 . Specifically, each proximal end of attachment axis  77  may fit into the cut-outs of the arm support portions  52 , such that attachment axis  77  may not readily be displaced from arm support portions  52 , and movable member  70  may rotate freely about attachment axis  77 . Consequently, when attachment axis  77  is supported by arm support portion  52 , movable member  70  is allowed to rotate with attachment axis  77  as a center of rotation. Moreover, referring to  FIG. 1 , blocking portion  71  may be located within detection portion  40 , and float portion  73  may be located proximal to the bottom side of the wall confronting the wall on which detection portion  40  is provided. 
         [0032]    The volume from attachment axis  77  to float portion  73  may be substantially greater than the volume from attachment axis  77  to blocking portion  71 . Specifically, the volumes may be selected, such that when float portion  73  is located within the ink, a clockwise moment in  FIG. 1  applied to movable member  70  from forces of gravity and buoyancy is greater than the counterclockwise moment, and when a portion of float portion  73  is exposed from the ink surface, the clockwise moment and the counterclockwise moment may be substantially equal. Consequently, after a portion of float portion  73  is exposed from the ink surface, as the amount of ink decreases and the ink surface moves further downward, float portion  73  follows the ink surface and also moves downward. When float portion  73  moves downward, movable member  70  rotates with attachment axis  77  as the rotation center, and blocking portion  71  moves upward. 
         [0033]    Referring to  FIG. 6 , when a force rotating the movable member clockwise in  FIG. 6  acts on movable member  70 , blocking portion  71  contacts contact member  40   a  within translucent portion  40 , and the clockwise rotation of movable member  70  is regulated, such that blocking portion  71  prevents light transmitted from light-emitting portion  1014   a  from being transmitted to light-receiving portion  1014   b.    
         [0034]    In contrast, when the amount of ink within ink chamber  60  decreases, blocking portion  71  changes its position upward within translucent portion  40 . When there is substantially no ink within ink chamber  60 , float portion  73  contacts the bottom wall of ink chamber  60 , and light passes between light-emitting portion  1014   a  and light-receiving portion  1014   b , thereby providing an indication that there is substantially no ink within ink chamber  60 . 
         [0035]    Referring to  FIG. 5(   a ), a sensor  1014  may disposed in an installation portion  1010  of printer  1000 , and sensor  1014  may have a substantially c-shape. The open end of the c-shape may be a light-emitting portion  1014   a  which emits light, and the other end may be a light-receiving portion  1014   b  which receives light. Light-emitting portion  1014   a  and light-receiving portion  1014   b  project from installation surface  1013 . When light-receiving portion  1014   b  receives light emitted by light-emitting portion  1014   a , a signal may not be output to a control substrate provided in printer  1000 , and when light-receiving portion  1014   b  does not receive light emitted by light-emitting portion  1014   a , a signal may be output to the control substrate, or vice versa. 
         [0036]    On the bottom side of installation surface  1013  confronting ink supply portion  120 , an ink extraction tube  1015  may be provided so as to project, and on the top side confronting air-introduction portion  130  of installation surface  1013 , installation surface  1013  may be flat. An ink flow path  1013   a  may be connected to ink extraction tube  1015 , and ink passing through ink flow path  1013   a  may be supplied to a discharge port (not shown). An air introduction path  1013   b  may be formed on installation surface  1013  of the air-introduction portion  130  side, and air passing through air-introduction path  1013   b  may be introduced into ink chamber  60 . 
         [0037]    Referring to  FIG. 5(   b ), when ink cartridge  1  is attached to installation portion  1010 , ink extraction tube  1015  may be inserted into ink supply portion  120 , thereby creating a state in which ink may be supplied, a valve-opening portion  30   a  of air introduction portion  130  may contact installation surface  1013 , thereby creating a state in which air may be introduced, and translucent portion  40  may be positioned between light-emitting portion  1014   a  and light-receiving portion  1014   b  of sensor  1014 , thereby creating a state in which the amount of ink within ink chamber  60  may be determined. 
         [0038]    In order to manufacture ink cartridge  1 , body  10  and lid  50  of ink chamber  60  may be resin-molded. At such time, body  10  may be formed, such that the direction perpendicular to the wall on which ink supply path  20  and air-communicating path  30  are provided is the direction from which body  10  is extracted from the molding die. Lid  50  also may be formed, such that the direction that support members  51  and contact members  53  project is the direction from which lid  50  is extracted from the molding die. 
         [0039]    Next, a separately fabricated and assembled ink supply mechanism  80  and air-introduction mechanism  90  may be attached to ink supply path  20  and air-communicating path  30 , respectively, to form ink supply portion  120  and air-introduction portion  130 . Thereafter, attachment axis  77  of movable member  70  fabricated separately by resin-molding may be fitted into arm-supporting portion  52  of lid  50 . Main opening  11  of body  10  also may be covered by lid  50 . At such time, blocking portion  71  of movable member  70  may be disposed within translucent portion  40  of body  10 . Next, body  10  and lid  50  are welded together. The welding of body  10  and lid  50  may be performed without gaps to prevent leakage of ink stored in ink chamber  60 . 
         [0040]    As described above, ink cartridge  1  may comprise a bottomed box-shape body  10  having a main opening  11 , a lid  50  which closes main opening  11 , an ink chamber  60  which stores ink, and a movable member  70  supported in such a manner that it may rotate corresponding to the amount of ink remaining in ink chamber  60 . In the wall confronting main opening  11  of body  10  there is provided an ink supply path  20  which communicates with ink chamber  60 . Moreover, a pair of support members  51  may project from lid  50 , which face the inside of ink chamber  60  and support movable member  70 . Consequently, it is not difficult to extract body  10  from the molding die when resin-molding is performed, such that the extraction direction is direction perpendicular to the wall in which ink supply path  20  is formed, and is different from the case that a member supported by movable member  70  is provided on a bottom wall of body  10  when the ink cartridge is installed in printer  1000 . Consequently, it is possible to resin-mold the ink cartridge using an easily designed molding die. In addition, an air-communicating path  30  may be provided above translucent portion  40  on the wall confronting main opening  11  of body  10 . Consequently, air-communicating path  30  may be resin-molded using an easily designed molding die. 
         [0041]    While the invention has been described in connection with exemplary embodiments, it will be understood by those skilled in the art that other variations and modifications of the exemplary embodiments described above may be made without departing from the scope of the invention. Other embodiments will be apparent to those skilled in the art from a consideration of the specification or practice of the invention disclosed herein. It is intended that the specification and the described examples are considered merely as exemplary of the invention, with the true scope of the invention being indicated by the flowing claims.

Technology Category: b