Patent Publication Number: US-8985743-B2

Title: Printing fluid supply device and printing fluid cartridge

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     The present application claims priority to and the benefit of Japanese Application No. 2012-272971, which was filed on Dec. 14, 2012, the disclosure of which is incorporated herein by reference in its entirety. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a printing fluid cartridge configured to be mounted to a cartridge mounting portion and to a printing fluid supply device comprising the printing fluid cartridge and the cartridge mounting portion. 
     2. Description of Related Art 
     An image recording apparatus that uses ink to record an image on a sheet of recording paper has been conventionally known. The image recording apparatus has a recording head of an inkjet recording method and selectively ejects ink droplets from nozzles of the recording head toward the sheet of recording paper. When the ink droplets land on the sheet of recording paper, a desired image is recorded on the recoding paper. The image recording apparatus has an ink cartridge that stores ink to be supplied to the recording head. The ink cartridge can be removably mounted to a mounting portion of the image recording apparatus. The ink cartridge may be equipped with a circuit board on which an IC chip is mounted. The IC chip stores data about the color and material of ink stored in the ink cartridge, a remaining amount of ink, a maintenance state, and the like. Contact terminals on the circuit board are brought into electric contact with connection terminals provided at the mounting portion when the ink cartridge is mounted to the mounting portion, enabling the data stored in the IC chip to be read out. Such an image recording apparatus is disclosed in JP-A-2007-237657 for example. 
     When an ink cartridge is mounted to a mounting portion, an ink supply tube of the mounting portion is inserted into an ink supply portion of the ink cartridge. Therefore, the ink cartridge needs to be accurately positioned such that the ink supply portion is aligned with the ink supply tube. The ink cartridge also needs to be accurately positioned such that the contact terminals on the circuit board of the ink cartridge are aligned with the connection terminals of the mounting portion for the contact terminals to come into contact with the connection terminals. Nevertheless, it may be difficult to achieve high dimensional precision with which the ink supply portion and ink supply tube are aligned and the contact terminals and connection terminals are aligned. 
     SUMMARY OF THE INVENTION 
     Therefore, a need has arisen for a printing fluid supply device and a printing fluid cartridge, which overcome these and other shortcomings of the related art. A technical advantage of the present invention is that a stable electric contact between an electric interface and a contact is achieved. 
     According to an embodiment of the present invention, a printing fluid supply device comprises: a cartridge mounting portion; and a printing fluid cartridge configured to be inserted into the cartridge mounting portion in an insertion direction which is aligned with a first direction, wherein the printing fluid cartridge comprises: a cartridge body comprising a printing fluid chamber configured to store printing fluid therein; a printing fluid supply portion provided at the cartridge body and extending along the first direction, wherein the printing fluid supply portion is in fluid communication with the printing fluid chamber; an electric interface; and a support member comprising a support surface facing in a first sub direction and a rear surface positioned opposite the support surface and facing in a second sub direction opposite the first sub direction, wherein the first sub direction and the second sub direction constitute a second direction which is perpendicular to the first direction, wherein the electric interface is provided at the support surface, and the cartridge mounting portion comprises: a connection portion configured to be connected to the printing fluid supply portion and allow the printing fluid to flow out of the printing fluid chamber through the printing fluid supply portion; and a sandwiching portion comprising a first sandwiching piece and a second sandwiching piece, wherein the first sandwiching piece and the second sandwiching piece are spaced away from each other in the second direction, and configured to sandwich, in the second direction, the support member of the printing fluid cartridge inserted into the cartridge mounting portion, wherein the first sandwiching piece comprises a surface facing in the second sub direction, wherein the surface of the first sandwiching piece supports a contact configured to contact the electric interface, one of the first sandwiching piece and second sandwiching piece comprises a guide surface configured to contact the support member and guide the support member in the second direction during insertion of the printing fluid cartridge into the cartridge mounting portion, and the cartridge body has a first space and a second space formed therein, wherein the first space is opened in the insertion direction and the first sandwiching piece is configured to be inserted into the first space, and the second space is opened in the insertion direction and the second sandwiching piece is configured to be inserted into the second space, wherein the support surface of the support member faces the first space and the rear surface of the support member faces the second space, wherein the cartridge body is configured to hold the support member such that the support member is movable relative to the cartridge body in the second direction. 
     According to another embodiment of the present invention, a printing fluid cartridge configured to be inserted into a cartridge mounting portion in an insertion direction which is aligned with a first direction, the cartridge mounting portion comprising a connection portion, a first sandwiching piece supporting a contact, and a second sandwiching piece, the cartridge comprises a cartridge body comprising a printing fluid chamber configured to store printing fluid therein; a printing fluid supply portion provided at the cartridge body and extending along the first direction, wherein the printing fluid supply portion is configured to be connected to the connection portion, such that the printing fluid is allowed to flow out of the printing fluid chamber through the printing fluid supply portion; an electric interface configured to contact the contact supported by the first sandwiching piece; and a support member comprising a support surface facing in a first sub direction and a rear surface positioned opposite the support surface and facing in a second sub direction opposite the first sub direction, wherein the first sub direction and the second sub direction constitute a second direction which is perpendicular to the first direction, wherein the electric interface is provided at the support surface, wherein the cartridge body has a first space and a second space formed therein, wherein the first space is opened in the insertion direction so as to receive the first sandwiching piece therein, and the second space is opened in the insertion direction so as to receiver the second sandwiching piece therein, wherein the support surface of the support member faces the first space and the rear surface of the support member faces the second space, wherein the cartridge body is configured to hold the support member such that the support member is movable relative to the cartridge body in the second direction. 
     According to another embodiment of the present invention, a printing fluid cartridge comprises a cartridge body comprising a printing fluid chamber configured to store printing fluid therein; an electric interface; a support member comprising a support surface facing in a first sub direction and a rear surface positioned opposite the support surface and facing in a second sub direction opposite the first sub direction, wherein the electric interface is provided at the support surface; and a printing fluid flow path having an end which is opened to the outside of the cartridge body, wherein the printing fluid flow path extends from the end of the printing fluid flow path in a third sub direction toward the interior of the cartridge body, wherein the printing fluid flow path is configured to allow the printing fluid out of the printing fluid chamber therethrough, wherein the cartridge body has a first space and a second space formed therein, wherein the first space is opened in a fourth sub direction opposite the third sub direction, and the second space is opened in the fourth sub direction, wherein the third sub direction and the fourth sub direction constitute a first direction and the first sub direction and the second sub direction constitute a second direction which is perpendicular to the first direction, wherein the support surface of the support member faces the first space and the rear surface of the support member faces the second space, wherein the cartridge body is configured to hold the support member such that the support member is movable relative to the cartridge body in the second direction. 
     With this configuration, a stable electric contact between the electric interface and the contact may be achieved. 
     Other objects, features, and advantages will be apparent to persons of ordinary skill in the art from the following detained description of the invention and the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a more complete understanding of the present invention, needs satisfied thereby, and the objects, features, and advantages thereof, reference now is made to the following description taken in connection with the accompanying drawings. 
         FIG. 1  is a schematic, cross-sectional view of a printer comprising an ink supply device according to an embodiment. 
         FIG. 2  is a perspective view of an ink cartridge according to an embodiment. 
         FIG. 3  is a vertical, cross-sectional view of the ink cartridge. 
         FIG. 4A  is a vertical, cross-sectional view of a cartridge mounting portion. 
         FIG. 4B  is a perspective view of a sandwiching portion as viewed from below. 
         FIG. 4C  is a perspective view of the sandwiching portion as viewed from above. 
         FIG. 5  is a vertical, cross-sectional view of the ink cartridge and the cartridge mounting portion, during insertion of the ink cartridge into the cartridge mounting portion. 
         FIG. 6  is a vertical, cross-sectional view of the ink cartridge and cartridge mounting portion, during the insertion of the ink cartridge into the cartridge mounting portion, in which the ink cartridge is further inserted from the position illustrated in  FIG. 5 . 
         FIG. 7  is a vertical, cross-sectional view of the ink cartridge and the cartridge mounting portion, in which the ink cartridge has been inserted to an excessively inserted position. 
         FIG. 8  is a vertical, cross-sectional view of the ink cartridge and the cartridge mounting portion, in which the ink cartridge has been moved to a mounted position. 
         FIG. 9A  is a partial, vertical, cross-sectional view of the ink cartridge and the cartridge mounting portion according to a first modified embodiment, illustrating an IC board and the sandwiching portion, in which the ink cartridge is not mounted to the cartridge mounting portion. 
         FIG. 9B  is a partial, vertical, cross-sectional view of the ink cartridge and the cartridge mounting portion according to the first modified embodiment, illustrating the IC board and the sandwiching portion, in which the ink cartridge has been mounted to the cartridge mounting portion. 
         FIG. 10A  is a partial, perspective view of the ink cartridge and the cartridge mounting portion according to a second modified embodiment, illustrating the IC board and the sandwiching portion, in which the ink cartridge is not mounted to the cartridge mounting portion. 
         FIG. 10B  is a partial, perspective view of the ink cartridge and the cartridge mounting portion according to the second modified embodiment, illustrating the IC board and the sandwiching portion, in which the ink cartridge has been mounted to the cartridge mounting portion. 
         FIG. 11A  is a partial, cross-sectional view of the ink cartridge and the cartridge mounting portion according to a third modified embodiment, illustrating the IC board and the sandwiching portion, in a state corresponding to the state illustrated in  FIG. 5 . 
         FIG. 11B  is a partial, cross-sectional view of the ink cartridge and the cartridge mounting portion according to the third modified embodiment, illustrating the IC board and the sandwiching portion, in a state corresponding to the state illustrated in  FIG. 6 . 
         FIG. 11C  is a partial, cross-sectional view of the ink cartridge and the cartridge mounting portion according to the third modified embodiment, illustrating the IC board and the sandwiching portion, in a state corresponding to the state illustrated in  FIG. 7 . 
         FIG. 11D  is a partial, cross-sectional view of the ink cartridge and the cartridge mounting portion according to the third modified embodiment, illustrating the IC board and the sandwiching portion, in a state corresponding to the state illustrated in  FIG. 8 . 
         FIG. 12  is a perspective view of the ink cartridge according to a fourth modified embodiment. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION 
     Embodiments of the present invention, and their features and advantages, may be understood by referring to  FIGS. 1-12 , like numerals being used for like corresponding parts in the various drawings. In the embodiments below, a depth direction (front-rear direction)  53  is an example of a first direction, a height direction (up-down direction)  52  is an example of a second direction, and a width direction (left-right direction)  51  is an example of a third direction. 
     [Printer  10 ] 
     Referring to  FIG. 1 , a printer  10  is configured to record an image by selectively ejecting ink droplets to a sheet of recording paper, using an inkjet recording method. The printer  10  comprises an ink supply device  100  as an example of the printing fluid supply device. The ink supply device  100  comprises a cartridge mounting portion  110  and an ink cartridge  30  as an example of the printing fluid cartridge. The ink cartridge  30  is configured to be mounted to the cartridge mounting portion  110 . The cartridge mounting portion  110  has an opening  112  formed therein. The ink cartridge  30  is configured to be inserted into the cartridge mounting portion  110  and be removed from the cartridge mounting portion  110  through the opening  112 . 
     The ink cartridge  30  is configured to store ink to be used by the printer  10 . The printer  10  comprises a recording head  21  having nozzles  29  formed therein, an ink tube  20 , and a sub tank  28 . The ink cartridge  30  and the recording head  21  are connected via the ink tube  20  when the ink cartridge  30  is mounted to the cartridge mounting portion  110 . The sub-tank  28  is provided in the recording head  21 . The sub-tank  28  is configured to temporarily store ink that is supplied via the ink tube  20 . The recording head  21  is configured to selectively eject, from the nozzles  29 , the ink supplied from the sub-tank  28 , using the inkjet recording method. 
     The printer  10  comprises a paper supply tray  15 , a paper supply roller  23 , a conveying roller pair  25 , a platen  26 , a discharge roller pair  22 , and a discharge tray  16 . A conveying path  24  is formed from the paper supply tray  15  to the discharge tray  16 , and the conveying path  24  extends through the nip of the conveying roller pair  25 , between the platen  26  and the recording head  21 , and through the nip of the discharge tray  16 . A sheet of recording paper supplied by the paper supply roller  23  from the paper supply tray  15  to the conveying path  24  is conveyed onto the platen  26  by the conveying roller pair  25 . The recording head  21  selectively ejects ink to the sheet of recording paper passing over the platen  26 . Thus, an image is recorded on the sheet of recording paper. The recording paper that has passed the platen  26  is discharged by the discharge roller pair  22  to the discharge tray  16  provided at the downstream end of the conveying path  24 . 
     [Ink Cartridge  30 ] 
     Referring to  FIGS. 2 and 3 , the ink cartridge  30  is a container configured to store ink therein. The ink cartridge  30  comprises a main body  31 , and the main body  31  comprises an outer case defining the most of the exterior of the ink cartridge  30 . The main body  31  comprises an ink chamber  36  formed directly inside the outer case. In another embodiment, the main body  31  may comprise an internal frame positioned within the outer case, and the ink chamber  36  may be formed in the internal frame. The ink chamber  36  is configured to store ink therein. The ink cartridge  30  is an example of a printing fluid cartridge and the ink chamber  36  is an example of a printing fluid chamber. 
     The ink cartridge  30  is configured to be inserted into and removed from the cartridge mounting portion  110  in a direction indicated by an arrow  50  (see  FIG. 3 , the direction is named an insertion/removal direction  50 ) while the ink cartridge  30  is in an upright position, as shown in  FIGS. 2 and 3 , with the top surface of the ink cartridge  30  facing upward and the bottom surface of the ink cartridge  30  facing downward. The ink cartridge  30  is in the upright position when ink cartridge  30  is mounted to the cartridge mounting portion  110  in a mounted position. The Ink cartridge  30  is configured to be inserted into the cartridge mounting portion  110  in an insertion direction  56  and removed from the cartridge mounting portion  110  in a removal direction  55 . The insertion/removal direction  50  is a combination of insertion direction  56  and removal direction  55 . In this embodiment, the insertion direction  56 , removal direction  55 , and insertion/removal direction  50  are horizontal directions. In another embodiment, the insertion direction  56 , removal direction  55 , and insertion/removal direction  50  may be inclined relative to a horizontal plane. For example, when the insertion/removal direction  50  is the vertical direction, a front face of the ink cartridge  30  in the insertion direction  50  faces downward. The insertion/removal direction  50  is an example of a first direction, the removal direction is an example of a third sub direction, and the insertion direction  56  is an example of a fourth sub direction 
     The main body  31  of ink cartridge  30  has a three-dimensional shape formed with planar surfaces or curved surfaces, e.g., a substantially parallelepiped shape. The main body  31  has a width in the width direction (left-right direction)  51 , a height in a height direction (up-down direction)  52 , and a depth in a depth direction (front-rear direction)  53 . The width direction (left-right direction)  51 , height direction (up-down direction)  52 , and depth direction (front-rear direction)  53  are perpendicular to each other. The width of the main body  31  is less than the height and the depth of the main body  31 . When the ink cartridge  30  is in the mounted position, i.e., in the upright position, the width direction (left-right direction)  51  is parallel with a horizontal plane, the depth direction (front-rear direction)  53  also is parallel with the horizontal plane, and height direction  52  is parallel with the vertical direction, i.e., the gravitational direction. When the ink cartridge  30  is inserted into/removed from the cartridge mounting portion  110 , the depth direction  53  is parallel with the insertion/removal direction  50 , and the width direction and height direction  52  are perpendicular to the insertion/removal direction  50 . The height direction (up-down direction), i.e., the vertical direction or the gravitational direction is a combination of an upward direction and a downward direction. The upward direction is an example of a first sub direction, and the downward direction is an example of a second sub direction. 
     Referring to  FIGS. 2 and 3 , the main body  31  comprises a front wall  40  and a rear wall  42 . The front wall  40  is disposed on a front side of the main body  31  with respect to the insertion direction  56  and the rear wall  42  is disposed on a rear side of the main body  31  with respect to the insertion direction  56  when ink cartridge  30  is inserted into cartridge mounting portion  110 . The font wall  40  and the rear wall  42  at least partly overlap in depth direction  53 . The front wall  40  and the rear wall  42  at least partly overlap in the insertion/removal direction  50  when the ink cartridge  30  is inserted or removed into/from the cartridge mounting portion  110 . The main body  31  comprises side walls  37 ,  38 , each extending in the insertion/removal direction  50  and connected to the front wall  40  and rear wall the  42 . The side walls  37 ,  38  at least partly overlap in the width direction (left-right direction)  51 . The main body  31  comprises a top wall  39  connected to the upper ends of front wall  40 , rear wall  42 , and the side walls  37 ,  38 . The main body  31  comprises a bottom wall  41  connected to the lower ends of front wall  40 , rear wall  42 , and the side walls. The top wall  39  and the bottom wall  41  at least partly overlap in height direction (up-down direction)  52 . 
     The outer faces of the side walls  37  and  38  correspond to side surfaces of the ink cartridge  30 . The outer face of the front wall  40  corresponds to a front face of the ink cartridge  30 . The outer face of the rear wall  41  corresponds to a rear face of the ink cartridge  30 . The outer face of the top wall  39  corresponds to the top face of the ink cartridge  30 . The outer face of the bottom wall  42  corresponds to the bottom face of the ink cartridge  30 . The rear wall  41  is a wall that is visible when the main body  31  of the ink cartridge  30  is viewed in the insertion direction  56 . 
     Referring to  FIGS. 2 and 3 , the main body  31  comprises an ink amount detection portion  33  provided at the middle of the front wall  40  of the main body  31  in the height direction (up-down direction)  52 . The ink amount detection portion  33  has a rectangular parallelepiped box shape extending from the front wall  40  and the inside of the ink amount detection portion  33  is in fluid communication with the ink chamber  36 . The ink amount detection portion  33  has a pair of walls made of a translucent, e.g., transparent or semi-transparent resin that allows light, e.g., infrared light or visible light, emitted from an optical sensor  114  (see  FIG. 4 ) to pass therethrough in a direction, i.e., the width direction (left-right direction)  51  in this embodiment, which is perpendicular to the insertion/removal direction  50 . In other words, the walls constituting the ink amount detection portion  33  allows light to pass therethrough in the width direction (left-right direction)  51 . 
     Referring to  FIG. 3 , the ink cartridge  30  comprises a sensor arm  60  positioned in the ink chamber  36 . The sensor arm  60  comprises an arm  61 , an indicator portion  62 , which has a plate shape, at a first end of the arm  61 , and a float portion  63  at a second end of the arm  61 . The indicator portion  62  of the sensor arm  60  is positioned between the right and left walls of the ink amount detection portion  33  in the width direction (left-right direction)  51 . The indicator portion  62  is made of an opaque material. The sensor arm  60  is pivotally supported by a supporting shaft  64  extending in the width direction  51  in the ink chamber  36 . The sensor arm  60  is configured to pivot as the amount of ink stored in the ink chamber  36  changes. 
     When the sensor arm  60  pivots, the indicator portion  62  moves between a lower position located at a lower portion of the ink amount detection portion  33  and an upper position located at an upper position of the ink amount detection portion  33 . When the indicator portion  62  is in the upper position, the ink amount detection portion  33  allows the infrared light emitted from the optical sensor  114  to pass therethough, not being blocked by the indicator portion  62 . When the indicator portion  62  is in the lower position, the ink amount detection portion  33  prevents the infrared light emitted from the optical sensor  114  from passing therethrough or attenuates the light by being blocked by the indicator portion  62 . It can be determined that the amount of ink stored in the ink chamber  36  has become less than a predetermined amount by detecting the light transmission state of the ink amount detection portion  33 . 
     The ink cartridge  30  comprises an ink supply portion  34  provided at the front wall  40  of the main body  31  below the ink amount detection portion  33 . The ink supply portion  34  has a cylindrical outer shape and extends from the front wall  40  outwardly (that is, in the insertion direction  56 ) along the insertion/removal direction  50 . The ink supply portion  34  comprises an end in the insertion direction  56  and has an ink supply opening  71  formed at the end of the ink supply portion  34 . The ink supply portion  34  is an example of a printing fluid supply portion provided at the main body  31  and extending along the depth direction  53  and along the insertion/removal direction  50 . 
     The ink supply portion  34  has an ink flow path  72  formed therein, and the ink flow path  72  extends in the insertion/removal direction  50  from the ink supply opening  71  to ink chamber  36 . The ink flow path  72  is an example of a printing fluid flow path that has an end, i.e., the ink supply opening  71  that is opened to the outside of the main body  31  and extends from the ink supply opening  71  to the interior of the main body  31  in the removal direction  55  of the insertion/removal direction  50 . The ink supply portion  34  comprises an ink supply valve  70  and a coil spring  73  positioned in the ink flow path  72 . The ink supply valve  70  is configured to move so as to selectively open and close the ink supply opening  71 . The coil spring  73  is configured to bias the ink supply valve  70  toward the ink supply opening  71  such that the ink supply valve  70  closes the ink supply opening  71 . When the ink cartridge  30  is mounted to the cartridge mounting portion  110 , an ink needle  117  (see  FIG. 4 ) provided in the cartridge mounting portion  110  is inserted into the ink supply opening  71 , and contacts and moves the ink supply valve  70  away from the ink supply opening  71  against the biasing force of the coil spring  73 . Thus, ink stored in the ink chamber  36  flows through the ink flow path  72  to the ink needle  117 . 
     The ink supply portion  34  is not necessarily configured such that the ink supply opening  71  is selectively closed and opened by the ink supply valve  70 . In another embodiment, the ink supply opening  71  may be covered by a film or rubber, and when the ink cartridge  30  is mounted to the cartridge mounting portion  110 , the ink needle  117  may penetrates through the film or rubber for the ink supply opening  71  to be opened. Although not shown in the drawings, the main body  31  may have a communication opening to the atmosphere through air can pass between the ink chamber  36  and the outside of the ink cartridge  30 . 
     The main body  31  comprises a lock portion  45  at the top wall  39 . The lock portion  45  has a groove extending in the depth direction from the middle of the top wall  39  with respect to the depth direction  53  up to the rear wall  41 . The lock portion  45  comprises, at the end of the groove in the insertion direction  56 , a lock surface  46  that extends in the width direction (left-right direction)  51  and height direction (up-down direction)  52  of the ink cartridge  30 . The lock surface  46  is configured to contact a lock member  145  of the cartridge mounting portion  110  (see  FIG. 4 ) when the ink cartridge  30  is mounted to the cartridge mounting portion  110 . The lock surface  46  receives external force in a direction opposite to a direction in which the ink cartridge  30  is biased in the removal direction  55  when the ink cartridge  30  is mounted to the cartridge mounting portion  110 , i.e., receives force from the lock member  145  in this embodiment. The end of the groove in the removal direction  55  is open to the outside of the main body  31 . 
     The ink cartridge  30  comprises a pivot member  80  at the lock portion  45 . The pivot member  80  has, for example, a bent flat plate shape and is disposed such that its longitudinal direction is aligned with the depth direction  53 . The pivot member  80  has an axis  83  at a position at which the pivot member  80  is bent. The pivot member  80  is configured to pivot about the axis  83 . The pivot member  80  comprises a front end  81  and a rear end  82  with respect to the depth direction  53 , and the front end  81  of the pivot member  80  extends from the axis  83  toward the lock surface  46  and the rear end  82  of the pivot member  80  extends from the axis  83  toward the rear wall  41 . 
     When the pivot member  80  pivots to a position in which the front end  81  is in the uppermost position, the front end  81  extends outwardly beyond the top wall  39  of the main body  31 . When the front end  81  of the pivot member  80  is pressed downward, the pivot member  80  pivots clockwise as viewed in  FIG. 3 . When the pivot member  80  pivots to the clockwise end, the front end  81  is positioned close to the lower end of the lock surface  46 . The pivot member  80  may be formed integrally with the main body  31 . The pivot member  80  may be biased clockwise by a coil spring (not shown) or may pivot due to its own weight in one direction. 
     [IC Board  85 , IC Board Holding Portion  90 ] 
     Referring to  FIGS. 2 and 3 , the ink cartridge  30  comprises an IC board  85 , and the main body  30  comprises an IC board holding portion  90  configured to hold the IC board  85 . The IC board holding portion  90  is positioned at the top wall  39  of the main body  31  at a position which is closer to the front wall  40  than the lock portion  45  is. The IC board holding portion  90  has a space formed by cutting out a corner between the top wall  39  and front wall  40 . The space is opened to the outside of the main body  31  in the insertion direction  56  and in the upward direction of the height direction (up-down direction)  52 . The space is closed in the removal direction  55  by an outer surface of the main body  31 , which outer surface faces in the insertion direction  56 . The space is also closed in the downward direction of the height direction  52  by an outer surface of the main body  31 , which outer surface faces in the upward direction of the height direction (up-down direction)  52 . The space is also closed in the width direction (left-right direction)  51  by inner surfaces of the side walls  37  and  38 . 
     A groove  91  is formed in the inner surface of the side wall  38 , and the groove  91  extends in the depth direction  53 . The groove  91  in this embodiment has a rectangular parallelepiped shape. That is, the groove  91  has a rectangular cross section along the width direction  51  and height direction  52  and also has a rectangular cross section along the height direction  52  and depth direction  53 . The groove  91  is defined by a front wall surface  92 , a rear wall surface  93 , top wall surface  94 , a bottom wall surface  95 , and a side wall surface  96 . The front wall surface  92  extends in the width direction (left-right direction)  51  and the height direction (up-down direction)  52 . The rear wall surface  93  extends in the width direction (left-right direction)  51  and the height direction (up-down direction)  52 . The top wall surface  94  extends in the width direction (left-right direction)  51  and the depth direction (front-rear direction)  53 . The bottom wall surface  95  extends in the width direction (left-right direction)  51  and the depth direction (front-rear direction)  53 . The side wall surface  96  extends in the height direction  52  and the depth direction  53 . In this embodiment, the rear wall surface  93  is the same plane as the outer surface of the main body  31 , which outer surface faces in the insertion direction  56  and closes the above-described space of the IC board holding portion  90  in the removal direction  55 . 
     Although not illustrated, another groove is also formed at a position opposite to the groove  91  in the inner surface of the side wall  37 . That is, a pair of grooves, which extend in the depth direction  53  and face each other in the width direction  51 , is formed in the IC board holding portion  90 . The IC board  85  has substantially a rectangular parallelepiped shape. The ends of the IC board  85  in the width direction  51  are inserted into the grooves, i.e., the groove  91  and the corresponding groove in the inner surface of the side wall  37 , respectively. A distance between the side wall surface  96  of the groove  91  and the inner surface of the side wall  37  is less than the width of the IC board  85  in the width direction  51 . The distance between the side wall surface of the groove formed in the side wall  37  and the inner surface of the side wall  38  is less than the width of the IC board  85  in the width direction  51 . Accordingly, the IC board  85  does not come off the grooves. In this embodiment, the grooves formed in the inner surfaces of the side walls  37  and  38  have an identical shape, so the following description will focus on the groove  91 . 
     The IC board  85  comprises a top surface facing in the upward direction and a rear surface positioned opposite the top surface and facing in the downward direction. The ink cartridge  30  comprises electrodes  86 ,  87 , and  88  provided at the top surface of the IC board  85 . At the top surface of the IC board  85 , the electrodes  86 ,  87 , and  88  each extend in the depth direction  53  and are spaced away in the width direction  51 . The electrodes  86 ,  87 , and  88  are examples of an electric interface, the IC board  85  is an example of a support member, and the top surface of the IC board  85  is an example of a support surface. The electrodes  86 ,  87 , and  88  are, for example, a HOT electrode, a GND electrode, and a signal electrode. An IC chip (not illustrated), which is electrically connected to the electrodes  86 ,  87  and  88 , is mounted to the IC board  85 . The IC chip is a semiconductor integrated circuit configured to store data indicating information about the ink cartridge  30  such as, for example, a lot number, a date of manufacturing, and an ink color. The data can be read out of the IC chip by the printer  10  when the ink cartridge  30  is mounted to the cartridge mounting portion  110 . 
     The front wall surface  92  and rear wall surface  93 , which define the ends of the groove  91  in the depth direction (front-rear direction)  53 , face each other in the depth direction (front-rear direction)  53 . The distance between the front wall surface  92  and the rear wall surface  93  in the depth direction (front-rear direction)  53  (that is, the dimension of the groove  91  in the depth direction (front-rear direction)  53 ) is greater than the dimension of the IC board  85  in the depth direction  53 . That is, the IC board  85  is movable in the groove  91  in the depth direction  53 . In other words, the IC board holding portion  90  is configured to hold the IC board  85  such that the IC board  85  is movable relative to the main body  31  in the depth direction (front-rear direction)  53 . When the IC board  85  moves in the insertion direction  56  relative to the main body  31  and the front end of the IC board  85  contacts the front wall surface  92 , the movement of the IC board  85  in the insertion direction  56  is restricted. Similarly, when the IC board  85  moves in the removal direction  55  relative to the main body  31  and the rear end of the IC board  85  contacts the rear wall surface  93 , the movement of the IC board  85  in the removal direction  55  is restricted. That is, the front wall surface  92  and rear wall surface  93 , which define the ends of the groove  91  in the depth direction (front-rear direction)  53 , are an example of a range limiting portion configured to limit the range of the movement of the IC board  85  relative to the main body  31  in the depth direction (front-rear direction)  53 . 
     The top wall surface  94  and bottom wall surface  95 , which define the ends of the groove  91  in the height direction (up-down direction)  52 , face each other in the height direction (up-down direction)  52 . The distance between the top wall surface  94  and the bottom wall surface  95  in the height direction (up-down direction)  52  (that is, the dimension of the groove  91  in the height direction (up-down direction)  52 ) is greater than the dimension of the IC board  85  in the height direction (up-down direction)  52 . That is, the IC board  85  is movable in the groove  91  in the height direction (up-down direction)  52 . In other words, the IC board holding portion  90  is configured to hold the IC board  85  such that the IC board  85  is movable relative to the main body  31  in the height direction (up-down direction)  52 . When the IC board  85  moves in the upward direction and the top surface of the IC board  85  contacts the top wall surface  94 , the upward movement of the IC board  85  is restricted. Similarly, when the IC board  85  moves in the downward direction and the rear surface of the IC board  85  contacts the bottom wall surface  95 , the downward movement of the IC board  85  is restricted. That is, the top wall surface  94  and bottom wall surface  95 , which define the ends of the groove  91  in the height direction (up-down direction)  52 , are an example of a range limiting portion configured to limit the range of the movement of the IC board  85  relative to the main body  31  in the height direction (up-down direction)  52 . 
     The side wall surface  96 , which defines one end of the groove  91  in the width direction (left-right direction)  51 , and the side wall surface which defines one end of the groove formed in the inner surface of the side wall  37  (these surfaces will be referred to below as the pair of side wall surfaces) face each other in the width direction (left-right direction)  51 . The distance between the pair of side wall surfaces in the width direction (left-right direction)  51  is greater than the dimension of the IC board  85  in the width direction (left-right direction)  51 . That is, the IC board  85  is movable in the groove  91  in the width direction (left-right direction)  51 . In other words, the IC board holding portion  90  is configured to hold the IC board  85  such that the IC board  85  is movable relative to the main body  31  in the width direction (left-right direction)  51 . Assuming that the ink cartridge  30  is viewed in the removal direction  55 , when the IC board  85  moves to the right relative to the main body  31  and the right end surface of the IC board  85  contacts the side wall surface  96 , the movement of the IC board  85  to the right is restricted. Similarly, when the IC board  85  moves to the left relative to the main body  31  and the left end surface of the IC board  85  contacting a side wall surface corresponding and facing the side wall surface  96 , the movement of the IC board  85  to the left is restricted. That is, the pair of side wall surfaces is an example of a range limiting portion configured to limit the range of the movement of the IC board  85  relative to the main body  31  in the width direction (left-right direction)  51 . 
     In this embodiment, a movable distance of the IC board  85  in the width direction (left-right direction)  51  relative to the main body  31  is preferably less than the width of each electrodes  86 ,  87 , and  88  in the width direction  51 . For example, there only may be such a clearance between the IC board  85  and the pair of side wall surface that the movement of the IC board  85  in the height direction (up-down direction)  52  and depth direction (front-rear direction)  53  relative to the main body  31  is no impeded. 
     The above-described space in the IC board holding portion  90  is divided into an upper space  97  and a lower space  98  by the IC board  85 . The upper space  97  is formed above the IC board  85 . In other words, the top surface (that is, the support surface) of the IC board  85  faces the upper space  97 , e.g., is exposed to the upper space  97 . The upper space  97  is opened to the outside of the main body  31  in the upward direction and the insertion direction  56 . The upper space  97  is accessible from the outside of the main body  31  along the removal direction  55  at least up to a position which overlaps the electrodes  86 ,  87 , and  88  when the upper space  97  is viewed in the height direction (up-down direction)  52 . The upper space  97  is an example of a first space. 
     The lower space  98  is formed below the IC board  85 . In other words, the rear surface of the IC board  85  faces the lower space  98 , e.g., is exposed to the lower space  98 . The lower space  98  is opened to the outside of the main body  31  in the insertion direction  56 . The lower space  98  is accessible from the outside of the main body  31  along the removal direction  55  at least up to a position which overlaps the electrodes  86 ,  87  when the lower space  98  is viewed in the height direction (up-down direction)  52 . The lower space  98  is an example of a second space. 
     [Cartridge Mounting Portion  110 ] 
     Referring to  FIG. 4A , the cartridge mounting portion  110  comprises a case  101  having the opening  112  formed on a user-interface side of the printer  10 . The ink cartridge  30  is inserted into and is removed from the case  101  through the opening  112 . Although four ink cartridges  30 , storing cyan, magenta, yellow and black inks respectively, can be accommodated in the case  101 ,  FIG. 4A  illustrates a space of the case  101  in which one ink cartridge  30  can be accommodated. 
     The case  101  comprises an end surface  102  positioned opposite the opening  112  in the insertion/removal direction  50 . The cartridge mounting portion  110  comprises a connection portion  103  provided at a lower portion of the end surface  102 . The connection portion  103  is placed at a position corresponding to the ink supply portion  34  of the ink cartridge  30  mounted to the case  101 . 
     The connection portion  103  comprises the ink needle  117  and a holding groove  116 . The ink needle  117  is a resin tube, e.g., a cylindrical resin tube. The ink needle  117  is connected to the ink tube  20  at the outside of the case  101 . More specifically, the ink needle  117  is connected to a connector at the outside of the case  21  and the ink tube  20  is connected to the connector. The ink tube  20  connected to ink needle  117  at the outside of the case  101  extends in the upward direction along the outer surface of the case  101  and then extends to the recording head  21  of the printer  10 . In  FIG. 4(A) , the ink tube  20  is not illustrated. 
     The holding groove  116  is a groove, e.g., a cylindrical groove formed in the end surface  102 . The ink needle  117  is aligned with the central axis of the holding groove  116 . Referring to  FIGS. 7 and 8 , when the ink cartridge  30  is mounted to the cartridge mounting portion  110 , the ink supply portion  34  is inserted into the holding groove  116 . When this occurs, the cylindrical outer surface of the ink supply portion  34  comes into contact with the cylindrical inner surface of the end surface  102  defining the holding groove  116 . When the ink supply portion  34  is inserted into the holding groove  116 , the ink needle  117  is inserted into the ink supply opening  71  of the ink supply portion  34 . Thus, ink stored in the ink chamber  36  becomes ready to flow to the outside of the ink cartridge  30 . The ink that has flowed out of the ink chamber  36  is supplied through the ink needle  117  and ink tube  20  to the recording head  21 . 
     Referring to  FIG. 4A , the cartridge mounting portion  110  comprises the optical sensor  114  positioned at the end surface  102  of the case  101  above the connection portion  103 . The optical sensor  114  has a light emitting element provided at its one end and a light receiving element provided at its another end. The light emitting element is, for example, an LED or the like, and is configured to emit light in a horizontal direction (width direction (left-right direction  51 ) perpendicular to the insertion/removal direction  50 . The light receiving element is, for example, a phototransistor or the like, and is configured to receive light emitted from the light emitting element. The ink amount detection portion  33  of the ink cartridge  30  is configured to enter a space between the light emitting element and the light receiving element. When the ink amount detection portion  33  intersects an optical path of the optical sensor  114 , the optical sensor  114  is configured to detect the light transmission state of the ink amount detection portion  33 . 
     Referring to  FIG. 4A , the cartridge mounting portion  110  comprises a sandwiching portion  120  positioned at a top surface  104  of the case  101  adjacent to the end surface  102 . When the ink cartridge  30  is mounted to the cartridge mounting portion  110 , the sandwiching portion  120  is configured to sandwich the IC board  85  from both sides in the height direction  52 . The sandwiching portion  120  comprises a first sandwiching piece  121  and a second sandwiching piece  122 , which are spaced away from each other in the height direction (up-down direction)  52 . 
     The first sandwiching piece  121  extends from the end surface  102  along the top surface  104  of the case  101  in the removal direction  55 . When the ink cartridge  30  is mounted to the cartridge mounting portion  110 , the first sandwiching piece  121  faces the top surface of the IC board  85 . More specifically, the first sandwiching piece  121  is inserted into the upper space  97  of the IC board holding portion  90  in the removal direction  55  and reaches a position at which the first sandwiching piece  121  overlaps the electrodes  86 ,  87 , and  88  in the height direction (up-down direction)  52 . Referring to  FIG. 4B , the first sandwiching piece  121  comprises a bottom surface facing in the downward direction, and supports electrical contacts  124 ,  125 , and  126  provided at the bottom surface of the first sandwiching piece  121 . The contacts  124 ,  125 , and  126  are at such positions that they contact the electrodes  86 ,  87 , and  88  provided on the top surface of the IC board  85  when the ink cartridge  30  is mounted to the cartridge mounting portion  110 . The contacts  124 ,  125 , and  126  are provided on the bottom surface of the first sandwiching piece  121  and spaced away from each other in the width direction (left-right direction)  51 . The contacts  124 ,  125 , and  126  are configured to be resiliently deformed in the height direction (up-down direction)  52  when the IC board  85  is inserted between the first sandwiching piece  121  and the second sandwiching piece  122 . 
     The contact points  124 ,  125 , and  126  are electrically connected via an electric circuit to a calculating unit (not shown). The calculating unit comprises, for example, a CPU, a ROM, a RAM, and the like. The calculating unit may be a controller of the printer  10 . When the contact  124  and HOT electrode, as one of the electrodes  86 ,  87 , and  88 , are mutually brought into electric conduction, a voltage Vc is applied to the HOT electrode. When the contact  125  and GND electrode, as one of the electrodes  86 ,  87 , and  88 , are mutually brought into electric conduction, the GND electrode is grounded. When the contact  124  and HOT electrode are mutually brought into electric conduction and the contact  125  and GND electrode are mutually brought into electric conduction, electric power is supplied to the IC chip on the IC board  85 . When the contact  126  and signal electrode, as one of the electrodes  86 ,  87 , and  88  are mutually brought into electric conduction, data stored in the IC chip becomes accessible. An output from the electric circuit is supplied to the calculating unit. 
     The second sandwiching piece  122  extends from the end surface  102  of the case  101  in the removal direction  55 . When the ink cartridge  30  is mounted to the cartridge mounting portion  110 , the second sandwiching piece  122  faces the rear surface of the IC board  85 . More specifically, the second sandwiching piece  122  is inserted into the lower space  98  of the IC board holding portion  90  in the removal direction  55  and reaches a position at which the second sandwiching piece  122  overlaps the electrodes  86 ,  87 , and  88  in the height direction (up-down direction)  52 . Referring to  FIG. 4C , the second sandwiching piece  122  comprises a guide surface  123  positioned at its end surface in the removal direction  55 , i.e., a surface facing in the removal direction  55 . The guide surface  123  is an inclined surface, the height of which is gradually increased in the insertion direction  56 . In other words, the lower side of the second sandwiching piece  122  extends more from the end surface of the case  101  than the upper side of the second sandwiching piece  122  extends from the end surface of the case  101 . The second sandwiching piece  122  extends up to a position at which the second sandwiching piece  122  overlaps the contacts  124 ,  125 , and  126  when the sandwiching portion  120  is viewed in the height direction (up-down direction)  52 . 
     Referring to  FIG. 4A , the cartridge mounting portion  110  comprises the lock member  145  positioned at the case  101 . The lock member  145  is configured to retain the ink cartridge  30  mounted to the cartridge mounting portion  110  in the mounted position. The lock member  145  is configured to pivot about a supporting shaft  147  positioned on the opening  112  side of the case  101  for example. Thus, the lock member  145  is configured to pivot clockwise and counterclockwise about the supporting shaft  147 . The lock member  145  comprises an locking end  146  positioned opposite to the supporting shaft  147  in the insertion/removal direction  50 . The locking end  146  is configured to contact the lock surface  46  of the ink cartridge  30 . When contacting the lock surface  46 , the locking end  146  retains the ink cartridge  30  at the mounted position in the case  101  against a force causing the ink cartridge  30  to move in the removal direction  55 . 
     A position of the lock member  145  in which the locking end  146  and lock surface  46  can contact each other (see  FIG. 8 ) is referred to as a lock position, and a position of the lock member  145  in which the locking end  146  and lock portion  45  do not contact each other (see  FIG. 5 ) is referred to as an unlock position. The lock member  145  pivots downward by its own weight. When the front end  81  of the pivot member  80  moves upward, the lock member  145  pivots upward about the supporting shaft  147 , and thereby moves from the lock position to the unlock position. 
     [Mounting of the Ink Cartridge  30  to the Cartridge Mounting Portion  110 ] 
     Referring to  FIGS. 5 to 8 , Mounting operation of the ink cartridge  30  to the cartridge mounting portion  110  will be described below with reference to  FIGS. 5 to 8 . 
     First, referring to  FIG. 5 , when the ink cartridge  30  is inserted into the cartridge mounting portion  110  in the insertion direction  56 , the lock member  145  is moved upward by the top wall  39  of the main body  31  and the lock member  145  moves from the lock position to the unlock position. Before the front end of the IC board  85  contacts the guide surface  123 , the IC board  85  is in contact with the bottom wall surface  95  of the groove  91  and is held at an arbitrary position in the groove  91  in the depth direction (front-rear direction)  53 . 
     Subsequently, referring to  FIG. 6 , when the ink cartridge  30  is further inserted into the cartridge mounting portion  110  in the insertion direction  56 , the IC board  85  contacts the guide surface  123  and moves relative to the main body  31  in the depth direction (front-rear direction)  53 . That is, the IC board  85  moves relative to the main body  31  in the removal direction  55 , and then the rear end of the IC board  85  contacts the rear wall surface  93  of the groove  91 . The IC board  85  also moves upward along the guide surface  123 . 
     Subsequently, referring to  FIG. 7 , when the ink cartridge  30  is inserted up to a position in which the ink supply portion  34  comes into the holding groove  116 , the ink needle  117  is inserted into the ink supply opening  71  of the ink supply portion  34 . The ink supply valve  70  pressed by the ink needle  117  is separated away from the ink supply opening  71  against the biasing force of the coil spring  73 . The IC board  85  is inserted between the first sandwiching piece  121  and the second sandwiching piece  122  while pressing contacts  124 ,  125 , and  126  in the upward direction, such that the IC board  85  is sandwiched by the first sandwiching piece  121  and second sandwiching piece  122  in the height direction (up-down direction)  52 . The electrodes  86 ,  87  and  88  and the contacts  124 ,  125  and  126  contact each other, electrically connecting the IC chip on the IC board  85  to the calculating unit of the printer  10 . The second sandwiching piece  122  contacts the rear surface of the IC board  85 . 
     Moreover, referring to  FIG. 7 , the lock member  145 , which has reached the lock portion  45  of the main body  31 , pivots downward and moves to the lock position because the lock member  145  is no longer supported by the top wall  39  of the main body  31 . Then, the locking end  146  and the lock surface  46  face each other in the depth direction (front-rear direction)  53 . The ink cartridge  30  illustrated in  FIG. 7  is in an excessively inserted state (overshooting), in which the front end of the ink supply portion  34  contacting the end surface of the holding groove  116 , and the locking end  146  and the lock surface  46  are separated away from each other in the depth direction (front-rear direction)  53 . 
     Accordingly, when the force pressing the ink cartridge  30  in the insertion direction  56  is removed in the state illustrated in  FIG. 7 , i.e., when a user stops inserting the ink cartridge  30  and remove his/her finger off the ink cartridge  30 , the ink cartridge  30  retracts, in the removal direction  55 , to a position in which the locking end  146  and lock surface  46  come into contact as illustrated in  FIG. 8 . This is because the compressed coil spring  73  expands in the insertion/removal direction  50  and applies a force to the main body  31  in the removal direction  55 . Thus, the lock member  145  retains the ink cartridge  30  in the cartridge mounting portion  110  against the force causing the ink cartridge  30  to move in the removal direction  55 . The front end  81  of the pivot member  80  in  FIG. 8  is positioned below the lock member  145 . The rear end  82  of the pivot member  80  is separated from the bottom surface of the groove in the lock portion  45  and is positioned above the top wall  39  of the main body  31 . In this embodiment, the position of the ink cartridge  30  in  FIG. 7  is called the excessively inserted position, and the position of the ink cartridge  30  in  FIG. 8  is called the mounted position. 
     The front end of the ink supply portion  34  in the mounted position is slightly spaced away from the end surface of the holding groove  116 . However, the ink needle  117  is still in the ink supply portion  34  and is separating the ink supply valve  70  away from the ink supply opening  71 . Therefore, it is possible for ink to flow out of the ink chamber  36  through an opening (not illustrated) formed in the front end of the ink needle  117 . Similarly, in the mounted position, the ink amount detection portion  33  is positioned such that its light transmission state is detected by the optical sensor  114 . 
     In the state illustrated in  FIG. 7 , the IC board  85  has been already sandwiched by the first sandwiching piece  121  and second sandwiching piece  122 , and therefore even if the ink cartridge  30  retracts from the excessively inserted position to the mounted position, the position of the IC board  85  remains unchanged. The rear end of the IC board  85  is thus separated away from the rear wall surface  93  of the groove  91 . The electrodes  86 ,  87  and  88  and the contacts  124 ,  125  and  126  remain in contact. This completes mounting of the ink cartridge  30  to the cartridge mounting portion  110 . 
     When the ink in the ink chamber  36  in the ink cartridge  30  is consumed, the used ink cartridge  30  is removed from the cartridge mounting portion  110  and a new ink cartridge  30  is mounted. 
     When the ink cartridge  30  is removed from the cartridge mounting portion  110 , the rear end  82  of the pivot member  80  is pressed downward by a user. The front end  81  of the pivot member  80  is thereby moved upward and is separated away from the bottom surface of the lock portion  45 . The lock member  145  pivots upward from the lock position to the unlock position due to this movement of the front end  81 , and the ink cartridge  30  is released from the state in which the ink cartridge  30  is retained by the lock member  145 . 
     When the lock member  145  pivots to the unlock position, the ink cartridge  30  is moved in the removal direction  55  due to the force causing ink cartridge  30  to move in the removal direction  55 . When the ink cartridge  30  is moved in the removal direction  55 , the ink needle  117  is pulled out of the ink supply portion  34 . Therefore, the ink supply valve  70  is pressed by the coil spring  73  and blocks the ink supply opening  71 . 
     When the ink cartridge  30  is further moved in the removal direction  55 , the IC board  85  moves relative to the main body  31  in the groove  91  in the insertion direction  56 . The IC board  85  then contacts the front wall surface  92 , and moves together with the main body  31  in the removal direction  55  and is removed from the sandwiching portion  120 . Thus, the electrodes  86 ,  87  and  88  and the contacts  124 ,  125  and  126  are separated away from each other, releasing the electric connection between the IC chip on the IC board  85  and the calculating unit of the printer  10 . 
     In this embodiment, by the ink needle  117  being inserted into the ink supply opening  71 , the position of the ink cartridge  30  relative to the cartridge mounting position  110  is fixed. On the other hand, the IC board  85  is held so as to be movable relative to the main body  31  in the width direction (left-right direction)  51 , height direction (up-down direction)  52 , and depth direction (front-rear direction)  53 . Accordingly, the IC board  85  is moved to an appropriate position while being guided by the guide surface  123  and is sandwiched by the sandwiching portion  120  during the mounting of the ink cartridge  30  to the cartridge mounting portion  110 . As a result, stable electric contacts can be realized between the electrodes  86 ,  87  and  88  and the contacts  124 ,  125  and  126  without having to apply an unreasonable force to the IC board  85 . 
     The ink cartridge  30  in this embodiment has a shape with a relatively long height dimension. Because the IC board  85  can move to an appropriate position in the height direction (up-down direction)  52  as described above, even if the position of the ink cartridge  30  relative to the cartridge mounting portion  110  is fixed at the lower portion of the main body  31  at which the ink supply portion  34  is provided, stable electric contacts can be realized between the electrodes  86 ,  87  and  88  and the contacts  124 ,  125  and  126  at the upper portion of the main body  31 . Because the IC board  85  is positioned above the ink supply portion  34 , even if ink leaks from the ink supply portion  34 , the IC board  85  is not contaminated by the ink 
     In this embodiment, the second sandwiching piece  122  extends to a position at which it overlaps the contacts  124 ,  125 , and  126  when viewed in the height direction (up-down direction)  52 , and the first sandwiching piece  121  and second sandwiching piece  122  can access a position at which they overlap the electrodes  86 ,  87 , and  88  in the upper space  97  and lower space  98  when viewed in the height direction (up-down direction)  52 . As a result, the sandwiching portion  120  can stably sandwich the IC board  85 . 
     In this embodiment, because the ink cartridge  30  is pressed to the excessively inserted position with the IC board  85  contacting the rear wall surface  93  of the groove  91 , the position of IC board  85  is fixed in the depth direction (front-rear direction)  53 , and therefore the electrodes  86 ,  87  and  88  and the contacts  124 ,  125  and  126  can reliably contact each other. As a result, the dimensions of the electrodes  86 ,  87  and  88  in the depth direction (front-rear direction)  53  can be shortened while stable electric contacts are maintained between the electrodes  86 ,  87  and  88  and the contacts  124 ,  125  and  126 . 
     Moreover, because the ink cartridge  30  retracts from the excessively inserted position to the mounted position with the IC board  85  being sandwiched by the sandwiching portion  120 , there is no friction between the electrodes  86 ,  87  and  88  and the contacts  124 ,  125  and  126  during retraction of the ink cartridge  30 . As a result, it is possible to suppress the wear of the contacts  124 ,  125  and  126 . 
     First Modified Embodiment 
     Referring to  FIGS. 9A and 9B , a first modified embodiment will be described. Detailed descriptions common to the above-described embodiment will be omitted and differences from the above-described embodiment will be mainly described. The first modified embodiment differs from the above-described embodiment in that the ink cartridge  30  comprises a board cover member  130  positioned in the upper space  97  and a board cover member  131  positioned in the lower space  98 . 
     Referring to  FIGS. 9A and 9B , the board cover member  130  is resiliently supported by a coil spring  132 . One end of the coil spring  132  is linked to a surface of the board cover member  130 , which surface faces in the removal direction  55 , and the other end of the coil spring  132  is linked to an outer surface of the main body  31 , which outer surface faces in the insertion direction  56 . The board cover member  130  is an example of a first movable member. When the ink cartridge  30  is not mounted to the cartridge mounting portion  110 , that is, when the coil spring  132  is maintained at its natural length, the board cover member  130  covers the top surface of the IC board  85  at the upper space  97  as illustrated in  FIG. 9A . The position of the board cover member  130  illustrated in  FIG. 9A  is a first position. 
     The board cover member  130  contacts the front end of the first sandwiching piece  121  during the insertion of the ink cartridge  30  into the cartridge mounting portion  110 . The board cover member  130  pressed by the first sandwiching piece  121  in the removal direction  55  moves to a position retracted from the upper space  97  against the biasing force of the coil spring  132  as illustrated in  FIG. 9B , exposing the top surface of the IC board  85  to the upper space  97 . The position of the board cover member  130  illustrated in  FIG. 9B  is a second position. That is, when the ink cartridge  30  is mounted to the cartridge mounting portion  110 , the first sandwiching piece  121  is inserted into the upper space  97 , replacing the board cover member  130 , and contacts the top surface of the IC board  85 . 
     Referring to  FIGS. 9A and 9B , the board cover member  131  is resiliently supported by a coil spring  133 . One end of the coil spring  133  is linked to a surface of the board cover member  131 , which surface faces in the removal direction  55 , and the other end of the coil spring  133  is linked to an outer surface of the main body  31 , which outer surface faces in the insertion direction  56 . The board cover member  131  is an example of a second movable member. When the ink cartridge  30  is not mounted to the cartridge mounting portion  110 , that is, when the coil spring  133  is maintained at its natural length, the board cover member  131  covers the rear surface of the IC board  85  at the lower space  98  as illustrated in  FIG. 9A . The position of the board cover member  131  illustrated in FIG.  9 A is a third position. 
     The board cover member  131  contacts the front end of the second sandwiching piece  122  during the insertion of the ink cartridge  30  into the cartridge mounting portion  110 . The board cover member  131  pressed by the second sandwiching piece  122  in the removal direction  55  moves to a position retracted from the lower space  98  against the biasing force of the coil spring  133  as illustrated in  FIG. 9B , exposing the rear surface of the IC board  85  to the lower space  98 . The position of the board cover member  131  illustrated in  FIG. 9B  is a fourth position. That is, when the ink cartridge  30  is mounted to the cartridge mounting portion  110 , the second sandwiching piece  122  is inserted into the lower space  98 , replacing the board cover member  131 , and contacts the rear surface of the IC board  85 . 
     The top surface and rear surface of the IC board  85  do not need to be always exposed to the upper space  97  and lower space  98  as in this first modified embodiment. That is, when the ink cartridge  30  is not mounted to the cartridge mounting portion  110 , the IC board  85  may be covered by the board cover member  130  and board cover member  131 . In other words, the upper space  97  and lower space  98  only need to be formed so as to receive the first sandwiching piece  121  and second sandwiching piece  122  during the mounting of the ink cartridge  30  to the cartridge mounting portion  110 . 
     In the first modified embodiment, the IC board  85  can be protected when, for example, the ink cartridge  30  is shipped from a factory. More specifically, the IC chip and electrodes  86 ,  87 , and  88  mounted on the IC board  85  can be protected by the board cover member  130 , which covers the top surface of the IC board  85 . By the board cover member  131 , which supports the IC board  85  from below, it is also possible to prevent the IC board  85  from being deformed or damaged by an external force exerted on the IC board  85 . 
     In the first modified embodiment, both the board cover member  130  and board cover member  131  are provided. However, in another embodiment, only any one of the board cover member  130  and board cover member  131  may be provided. 
     In the first modified embodiment, the board cover member  130  is moved from the first position to the second position by the first sandwiching piece  121  and the board cover member  131  is moved from the third position to the fourth position by the second sandwiching piece  122 . However, in another embodiment, a user may remove the board cover member  130  and board cover member  131  before the ink cartridge  30  is mounted to the cartridge mounting portion  110 . 
     Second Modified Embodiment 
     Next, referring to  FIG. 10  a second modified embodiment will be described. Detailed descriptions common to the above-described embodiment will be omitted and differences from the above-described embodiment will be mainly described. The second modified embodiment differs from the above-described embodiment in that the ink supply device  100  comprises a positioning portion  106  configured to determine the positioning of the IC board  85  relative to the cartridge mounting portion  110  in the width direction (left-right direction)  51 . That is, in the second modified embodiment, a movable distance of the IC board  85  in the width direction (left-right direction)  51  relative to the main body  31  does not necessarily need to be less than the width of each of the electrodes  86 ,  87 , and  88  in the width direction (left-right direction)  51 . 
     Referring to  FIG. 10A , the positioning portion  106  comprises a notch portion  107  formed at the central part of the IC board  85  in the width direction (left-right direction)  51  and a protrusion  108  extending at the central part of the top surface of the second sandwiching piece  122  in the width direction (left-right direction)  51 . The notch portion  107  comprises a pair of wall surfaces spaced away from and facing each other in the width direction (left-right direction)  51 , and a space formed between the pair of wall surfaces of the notch portion  107  has a distal end and a based end opposite the distal end in the depth direction (front-rear direction)  53 . The distal end of the space is opened at the front end of the IC board  85 , facing the cartridge mounting portion  110 , in the insertion direction  56 . A distance of the pair of wall surfaces of the notch portion  107  in the width direction (left-right direction)  51  is more narrowed at a position closer to the base end than at a position closer to the distal end. The pair of wall surfaces cross at the base end. The notch portion  107  is an example of a guide portion and the protrusion  108  is an example of a guide objective portion. 
     The protrusion  108  moves relative to the notch portion  107  between the pair of wall surfaces of the notch portion  107  in the removal direction  55  and reaches the base end of the space of the notch portion  107  as illustrated in  FIG. 10B  during the insertion of the ink cartridge  30  to the cartridge mounting portion  110 . When the ink cartridge  30  is inserted into the cartridge mounting portion  110  with the electrodes  86 ,  87 , and  88  of the IC board  85  shifted from the contacts  124 ,  125 , and  126  in the width direction (left-right direction)  51 , the protrusion  108  contacts one of the pair of wall surfaces of the notch portion  107 , such that the IC board  85  moves between the first sandwiching piece  121  and the second sandwiching piece  122  in the insertion direction  56  while moving in the width direction (left-right direction)  51 . As a result, the position of the IC board  85  relative to the cartridge mounting portion  110  in the width direction (left-right direction)  51  is fixed portion  110 , and therefore the widths of the electrodes  86 ,  87  and  88  in the width direction (left-right direction)  51  can be shortened while stable electric contacts are maintained between the electrodes  86 ,  87  and  88  and the contacts  124 ,  125  and  126 . 
     In another embodiment, the notch portion  107  may be formed at the cartridge mounting portion  110  (sandwiching portion  120 ) and the protrusion  108  may be provide at the IC board  85 . The positions of the notch portion  107  and protrusion  108  are not limited to the central parts of the IC board  85  and second sandwiching piece  122  in the width direction  51 . The notch portion  107  and protrusion  108  may be provided at any positions as long as they do not interfere with the electrodes  86 ,  87  and  88  or the contacts  124 ,  125  and  126 . 
     Third Modified Embodiment 
     Referring to  FIGS. 11A to 11D , a third modified embodiment will be described with reference to  FIG. 11 . Detailed descriptions common to the above-described embodiment will be omitted and differences from the above-described embodiment will be mainly described. The third modified embodiment differs from the above-described embodiment in that the rear wall surface  93 , which defines the groove  91 , is resiliently movable in the depth direction (front-rear direction)  53 . The rear wall surface  93  in the above-described embodiment is the same plane as the outer surface of the main body  31 , which outer surface faces in the insertion direction  56  and closes the space formed in the IC board holding portion  90  in the removal direction  55 . By contrast, the rear wall surface  93  in the third modified embodiment is provided on a wall member  135 , which is movable in the groove  91  in the insertion/removal direction  50 . 
     More specifically, referring to  FIGS. 11A to 11D , the IC board holding portion  90  comprises the wall member  135  and a coil spring  136  supporting and biasing the wall member  135  in the insertion direction  56 . The coil spring  136  contacts a surface of the wall member  135 , which surface faces in the removal direction  55 . A surface of the wall member  135  facing in the insertion direction  56  comprises the rear wall surface  93  of the groove  91 . A wall surface  127  of the sandwiching portion  120  facing in the removal direction  55  and positioned between the first sandwiching piece  121  and the second sandwiching piece  122  at the deepest part of the sandwiching portion  120  in the insertion direction  56  is an example of a movement limiting portion. The wall surface  127  as the movement limiting portion is configured to limit the movement of the IC board  85  relative to the cartridge mounting portion  110  in the insertion direction  56 . The coil spring  136  is an example of an resilient member. 
     The wall member  135  is a substantially T-shaped (or cross-shaped) member having a protrusion (not illustrated) extending toward both ends in the width direction (left-right direction)  51  when viewed in the removal direction  55 . The both ends of the protrusion of the wall member  135  is inserted into the pair of grooves formed in the IC board holding portion  90 , and the wall member  135  is movable in the insertion/removal direction  50  by being guided in the pair of grooves. That is, the groove  91  in the third modified embodiment is divided by the wall member  135  into an insertion-direction- 56 -side area and a removal-direction- 55 -side area relative to the wall member  135 . In the third modified embodiment, the IC board  85  is held in the insertion-direction- 56 -side area of the groove  91  relative to the wall member  135 . 
     Referring to  FIG. 11A , the wall member  135  is in the most frontward position in the groove  91  in the insertion direction  56  when the ink cartridge  30  is not mounted to the cartridge mounting portion  110 . Subsequently, during the insertion of the ink cartridge  30  into the cartridge mounting portion  110 , even if the IC board  85  pressed by the guide surface  123  contacts the rear wall surface  93 , the wall member  135  does not move in the groove  91  in the removal direction  55  as illustrated in  FIG. 11B . That is, the coil spring  136  biases the wall member  135  in the insertion direction  56  with a force stronger than a force with which the guide surface  123  presses the IC board  85  in the removal direction  55 . 
     When the ink cartridge  30  is further inserted into the cartridge mounting portion  110  in the insertion direction  56 , the front end of the IC board  85  contacts the wall surface  127  as the movement limiting portion. Thus, the movement of the IC board  85  in the insertion direction  56  is restricted. That is, the position of the IC board  85  relative to the cartridge mounting portion  110  in the depth direction (front-rear direction)  53 , i.e., the insertion/removal direction  50  is fixed, and the electrodes  86 ,  87  and  88  and the contacts  124 ,  125  and  126  contact each other. The IC board  85  is sandwiched by the wall surface  127  as the movement limiting portion and the wall member  135  from both sides in the depth direction (front-rear direction)  53 , i.e., the insertion/removal direction  50 . 
     Subsequently, when the ink cartridge  30  is inserted to the excessively inserted position, the wall member  135  pressed by the rear end of the IC board  85  moves in the removal direction  55  against the biasing force of the coil spring  136  as illustrated in  FIG. 11C . That is, the insertion-direction- 56 -side area of the groove  91  relative to the wall member  135  is expanded in the removal direction  55 . When the ink cartridge  30  moves from the excessively inserted position to the mounted position, the wall member  135  moves in the insertion direction  56  as illustrated in  FIG. 11D . That is, the insertion-direction- 56 -side area of the groove  91  which has been expanded in the removal direction  55  is contracted in the insertion direction  56 . 
     As described above, the wall member  135  is configured to move in the groove  91  in the removal direction  55  by the wall surface  127  as the movement limiting portion  127  limiting the movement of the IC board  85  in the insertion direction  56 . In other words, the wall member  135  is configured to resiliently expand the range of the movement of the IC board  85  relative to the main body  31  in the removal direction  55 . The wall member  135  is movable in the depth direction  53  to prevent an excessive force from acting on the IC board  85  sandwiched by the wall surface  127  as the movement limiting portion and the wall member  135 . 
     Forth Modified Embodiment 
     Referring to  FIG. 12 , a fourth modified embodiment be described. Detailed descriptions common to the above-described embodiment will be omitted and differences from the above-described embodiment will be mainly described. The fourth modified embodiment differs from the above-described embodiment in that the IC board holding portion  90  comprises a pair of mounting portions  140 , a columnar member  141 , and a removal preventing portion  142 . 
     Referring to  FIG. 12 , the pair of mounting portions  140  extend along the inner surfaces of the side walls  37  and  38  in the depth direction (front-rear direction)  53  in the IC board holding portion  90 . The pair of mounting portions  140  faces in the upward direction of the height direction (up-down direction)  52 . The columnar member  141  extends in the upward direction of the height direction (up-down direction)  52  from the bottom surface that closes the space of the IC board holding portion  90  in the downward direction of the height direction (up-down direction)  52 . The columnar member  141  has a rectangular parallelepiped shape. The IC board  85  has an opening  89  formed therethrough in the height direction (up-down direction)  52  at a position closer to the rear end of the IC board  85  than the electrodes  86 ,  87 , and  88  are. The opening  89  has a rectangular parallelepiped shape. 
     The IC board  85  is placed on the pair of mounting portions  140 . The columnar member  141  is inserted into the opening  89 . The columnar member  141  has a dimension which is greater than the dimension of the IC board  85  in the height direction (up-down direction)  52 . The removal preventing portion  142 , which prevents the columnar member  141  from being detached from the opening  89 , is fixed to the upper end of the columnar member  141 . That is, a dimension of the removal preventing portion  142  is greater than a dimension of the opening  89  in at least one of the width direction (left-right direction)  51  and depth direction (front-rear direction)  53 . 
     The IC board  85  is movable along the columnar member  141  in the height direction (up-down direction)  52 , from a position in which the IC board  85  contacts the pair of mounting portions  140  to a position in which the IC board  85  contacts the removal preventing portion  142 . That is, the pair of mounting portions  140  is configured to limit the range of downward movement of the IC board  85  relative to the main body  31 . The removal preventing portion  142  is configured to limit the range of upward movement of the IC board  85  relative to the main body  31 . The dimensions of the opening  89  in the width direction (left-right direction)  51  and the depth direction (front-rear direction)  53  are greater than the dimensions of the columnar member  141  in the width direction (left-right direction)  51  and the depth direction (front-rear direction)  53 , respectively. That is, the IC board  85  is movable relative to the main body  31  in the width direction (left-right direction)  51  and depth direction (front-rear direction)  53 . The columnar member  141  comprises a pair of surfaces extending in the height direction (up-down direction)  52  and the depth direction (front-rear direction)  53 , which pair of surfaces is configured to limit the range of the movement of the IC board  85  relative to the main body  31  in the width direction (left-right direction)  51 . The columnar member  141  comprises a pair of surfaces extending in the width direction (left-right direction)  51  and the height direction (up down direction)  52 , which pair of surfaces is configured to limit the range of the movement of the IC board  85  relative to the main body  31  in the depth direction (front-rear direction)  53 . 
     Other Modified Embodiments 
     In the above-described embodiment and modified embodiments, the electrodes  86 ,  87 , and  88  are provided on the top surface of the IC board  85  and the contacts  124 ,  125 , and  126  are provided on the bottom surface of the first sandwiching piece  121 . Nevertheless, the present invention is not limited to that structure. For example, in another embodiment the electrodes  86 ,  87 , and  88  may be provided on the rear surface of the IC board  85 , and the contacts  124 ,  125 , and  126  may be provided on the top surface of the second sandwiching piece  122 . The guide surface  123  may be provided on one of the first sandwiching piece  121  and second sandwiching piece  122 . 
     In the above-described embodiment and modified embodiments, the depth direction (front-rear direction)  53  is the first direction, the height direction (up-down direction)  52  is the second direction, and the width direction (left-right direction)  51  is the third direction. Nevertheless, the present invention is not limited to that structure. For example, the width direction (left-right direction)  51  may be the second direction and the height direction (up-down direction)  52  may be the third direction. That is, the ink cartridge  30  may hold the IC board  85 , such that the surface of the IC board  85  on which the electrodes  86 ,  87 , and  88  are provided faces to the left or right. 
     Moreover, in the above-described embodiment and modified embodiments, ink is used as printing fluid. Nevertheless, the present invention is not limited to using ink. That is, other liquids or toner and other fine particles may be used as printing fluid. 
     The above-described embodiment and modified embodiments can be arbitrarily combined without departing from the scope of the invention. 
     While the invention has been described in connection with various example structures and illustrative embodiments, it will be understood by those skilled in the art that other variations and modifications of the structures and embodiments described above may be made without departing from the scope of the invention. Other structures and embodiments will be understood by 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 merely illustrative and that the scope of the invention is defined by the following claims.