Patent Publication Number: US-11040543-B2

Title: Tank and liquid consuming apparatus including the same

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     The present application is a continuation of U.S. patent application Ser. No. 15/474,033, filed Mar. 30, 2017, which further claims priority from Japanese Patent Application No. 2016-073588, filed on Mar. 31, 2016, the disclosures of both of which are incorporated herein by reference in their entirety. 
    
    
     BACKGROUND 
     Field of the Invention 
     The present invention relates to a tank that can be replenished with liquid via an inlet and a liquid consuming apparatus including the tank. 
     Description of the Related Art 
     There is known a printer that includes: a tank that can be replenished with ink; and a recording head that records an image on a sheet by discharging, from a nozzle, the ink supplied from said tank. When the ink in the tank is consumed, a user can replenish with ink stored in a bottle, from an inlet of the tank. 
     SUMMARY 
     It is desirable that as much ink as possible is stored in the tank. On the other hand, it is desirable that an occupied space of the tank is as small as possible. 
     The present teaching was made in view of the previously mentioned circumstances, and has an object of providing a tank which enables an amount of liquid storable in the tank to be made large while an occupied space of the tank is maintained small. 
     According to an aspect of the present teaching, there is provided a tank configured to be installed in a liquid consuming apparatus having a liquid consuming unit and store liquid to be supplied to the liquid consuming unit, the tank including a casing that includes: a liquid storage chamber demarcated by a first surface and a second surface different from the first surface, and configured to store the liquid; an inlet provided to inject the liquid into the liquid storage chamber; and a liquid outflow port through which the liquid flows out from the liquid storage chamber to the liquid consuming unit, wherein the casing includes: a frame; a first film composing at least a part of the first surface; and a second film composing at least a part of the second surface. 
     Due to the above-described configuration, both a first surface and a second surface of a casing are configured by a thin film. Hence, a tank can be miniaturized. Moreover, an amount of liquid stored in a liquid storage chamber can be increased without changing external dimensions of the tank. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a perspective view of external appearance of a multifunction peripheral in a state where a cover is in a closed position, and  FIG. 1B  is a perspective view of external appearance of the multifunction peripheral in a state where the cover is in an open position. 
         FIG. 2  is a longitudinal cross-sectional view depicting schematically an internal structure of a printer unit. 
         FIG. 3  is a plan view depicting an arrangement of a carriage and a tank set. 
         FIG. 4  is a front perspective view of an ink tank for a color ink. 
         FIG. 5  is a rear perspective view of the ink tank for the color ink. 
         FIG. 6  is a right side view of the ink tank for the color ink. 
         FIG. 7  is a left side view of the ink tank for the color ink. 
         FIG. 8  is a front perspective view of an ink tank for a black ink. 
         FIG. 9  is a rear perspective view of the ink for the black ink. 
         FIG. 10  is a right side view of the ink tank for the black ink. 
         FIG. 11  is a left side view of the ink tank for the black ink. 
         FIG. 12A  is a schematic view of a cross section taken along XIIA-XIIA of  FIG. 6 , and  FIG. 12B  is a schematic view of a cross section taken along XIIB-XIIB of  FIG. 10 . 
         FIG. 13  is a schematic view of a cross section taken along XIIA-XIIA of  FIG. 6 . 
         FIG. 14  is a transverse cross-sectional view depicting schematically an ink tank for the color ink according to a modified embodiment. 
         FIG. 15  is a transverse cross-sectional view depicting schematically another ink tank for the color ink according to the modified embodiment. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     An embodiment of the present teaching will be described below. Note that the embodiment described below is merely an example of the present teaching, and it goes without saying that the embodiment of the present teaching may be appropriately changed in a range that does not alter the gist or essential characteristics of the present teaching. In the description below, a posture (the posture of  FIGS. 1A and 1B ) where a multifunction peripheral  10  and an ink tank  100  installed in the multifunction peripheral  10  are usably disposed in a horizontal plane will be described as a “usable posture”. An up-down direction  7  is defined with reference to the usable posture. A front-rear direction  8  is defined assuming a surface provided with an opening  13  of the multifunction peripheral  10  to be a front surface. A left-right direction  9  is defined viewing the multifunction peripheral  10  from the front surface. In the present embodiment, in the usable posture, the up-down direction  7  corresponds to a vertical direction, and the front-rear direction  8  and the left-right direction  9  correspond to horizontal directions. Note that an upward orientation is a component of the up-down direction  7 , and a downward orientation is also a component of the up-down direction  7 . Similarly, a leftward orientation and a rightward orientation are each components of the left-right direction  9 . A frontward orientation and a rearward orientation are each components of the front-rear direction  8 . 
     Overall Structure of Multifunction Peripheral  10   
     As depicted in  FIGS. 1A and 1B , the multifunction peripheral  10  (an example of a liquid consuming apparatus) has roughly a rectangular parallelepiped shape. A printer unit  11  that records an image on a sheet  12  (refer to  FIG. 2 ) by an ink-jet recording system, is provided in a lower section of the multifunction peripheral  10 . The printer unit  11  has a casing  14 . The opening  13  is formed in a front wall  14 A of the casing  14 . As depicted in  FIG. 2 , the following are disposed on the inside of the casing  14 , namely, a feed unit  15 , a feed tray  20 , a discharge tray  21 , a conveyance roller unit  54 , a recording unit  24 , a discharge roller unit  55 , a platen  42 , and a tank set  99 . The multifunction peripheral  10  has various functions such as a facsimile function and a print function. 
     Feed Tray  20 , Discharge Tray  21   
     The opening  13  is formed in the front surface and in a central section in the left-right direction  9  of the multifunction peripheral  10 . As depicted in  FIGS. 1A and 1B , the feed tray  20  is inserted/removed in the front-rear direction  8  into/from the multifunction peripheral  10 , via the opening  13 , by a user. The feed tray  20  can support a stacked plurality of the sheets  12 . The discharge tray  21  is disposed upwardly of the feed tray  20  and is inserted/removed along with the feed tray  20 . The discharge tray  21  supports the sheet  12  that has been discharged from between the recording unit  24  and the platen  42  by the discharge roller unit  55 . 
     Feed Unit  15   
     The feed unit  15  feeds to a conveyance passage  65  the sheet  12  supported by the feed tray  20 . As depicted in  FIG. 2 , the feed unit  15  includes a feed roller  25 , a feed arm  26 , and a shaft  27 . The feed roller  25  is rotatably supported by a distal end of the feed arm  26 . Reverse rotation of a conveyance motor (not illustrated) results in the feed roller  25  rotating in an orientation by which the sheet  12  is conveyed in a conveyance orientation  16 . Hereafter, the feed roller  25 , a conveyance roller  60 , and a discharge roller  62  rotating in an orientation by which the sheet  12  is conveyed in the conveyance orientation  16  will be described as “forward rotation”. The feed arm  26  is pivotably supported by the shaft  27  which is supported by a frame of the printer unit  11 . The feed arm  26  is biased so as to pivot to a feed tray  20  side by an elastic force due to the likes of its own weight or a spring. 
     Conveyance Passage  65   
     As depicted in  FIG. 2 , the conveyance passage  65  is a path that extends to a rear of the printer unit  11  from a rear end section of the feed tray  20 , makes a U-turn frontwards while extending upwardly at the rear of the printer unit  11 , and passes along a space between the recording unit  24  and the platen  42  to reach the discharge tray  21 . Part of the conveyance passage  65  is a space formed by an outer guide member  18  and an inner guide member  19  that face each other with a certain spacing between them on the inside of the printer unit  11 . As depicted in  FIGS. 2 and 3 , a portion between the conveyance roller unit  54  and the discharge roller unit  55 , of the conveyance passage  65  is provided in roughly the central section in the left-right direction  9  of the multifunction peripheral  10 , and extends in the front-rear direction  8 . The conveyance orientation  16  of the sheet  12  in the conveyance passage  65  is indicated by a dot-chain line arrow in  FIG. 2 . 
     Conveyance Roller Unit  54   
     As depicted in  FIG. 2 , the conveyance roller unit  54  is disposed upstream in the conveyance orientation  16  of the recording unit  24 . The conveyance roller unit  54  includes the conveyance roller  60  and a pinch roller  61  that face each other. The conveyance roller  60  is driven by the conveyance motor. The pinch roller  61  rotates in company with rotation of the conveyance roller  60 . The sheet  12  is nipped by the conveyance roller  60  that forwardly rotates by forward rotation of the conveyance motor, and the pinch roller  61 , whereby the sheet  12  is conveyed in the conveyance orientation  16 . 
     Discharge Roller Unit  55   
     As depicted in  FIG. 2 , the discharge roller unit  55  is disposed downstream in the conveyance orientation  16  of the recording unit  24 . The discharge roller unit  55  includes the discharge roller  62  and a spur wheel  63  that face each other. The discharge roller  62  is driven by the conveyance motor. The spur wheel  63  rotates in company with rotation of the discharge roller  62 . The sheet  12  is nipped by the discharge roller  62  that forwardly rotates by forward rotation of the conveyance motor, and the spur wheel  63 , whereby the sheet  12  is conveyed in the conveyance orientation  16 . 
     Recording Unit  24   
     As depicted in  FIG. 2 , the recording unit  24  is disposed between the conveyance roller unit  54  and the discharge roller unit  55  in the conveyance orientation  16 . The recording unit  24  is disposed so as to face the platen  42  in the up-down direction  7 , sandwiching the conveyance passage  65  between itself and the platen  42 . The recording unit  24  includes a carriage  23  and a recording head  39  (an example of a liquid consuming unit). 
     As depicted in  FIG. 3 , the carriage  23  is supported by guide rails  43 ,  44  that are provided extending in the left-right direction  9 , separated in the front-rear direction  8 . The guide rails  43 ,  44  are supported by the frame of the printer unit  11 . The carriage  23  is coupled to a publicly known belt mechanism provided in the guide rail  44 . The belt mechanism is driven by a carriage motor (not illustrated). The carriage  23  coupled to the belt mechanism makes a reciprocating movement along the left-right direction  9  by drive of the carriage motor. A range of movement of the carriage  23  reaches to rightward and leftward of the conveyance passage  65 , as depicted by the dot-chain lines of  FIG. 3 . 
     An ink tube  32  and a flexible flat cable  33  are extended out from the carriage  23 . 
     The ink tube  32  connects the tank set  99  and the recording head  39 . The ink tube  32  provides the recording head  39  with ink (an example of a liquid) stored in four ink tanks  100 B,  100 Y,  100 C,  100 M (these are sometimes indicated collectively as “ink tank  100 ”) that configure the tank set  99 . The ink tank  100  is an example of a tank. In detail, four ink tubes  32 B,  32 Y,  32 C,  32 M in which black, yellow, cyan, magenta inks flow are respectively extended out from the ink tanks  100 B,  100 Y,  100 C,  100 M, and connected to the carriage  23  in a state where these ink tubes  32 B,  32 Y,  32 C,  32 M have been bundled. The four ink tubes  32 B,  32 Y,  32 C,  32 M are sometimes described collectively as “ink tube  32 ”. 
     The flexible flat cable  33  electrically connects a control board on which a control unit (not illustrated) is mounted and the recording head  39 . The flexible flat cable  33  transmits to the recording head  39  a control signal outputted from the control unit. 
     As depicted in  FIG. 2 , the recording head  39  is mounted in the carriage  23 . A plurality of nozzles  40  are disposed in a lower surface of the recording head  39 . Tips of the plurality of nozzles  40  are exposed from the lower surface of the recording head  39 . Hereafter, a surface from which the tip of the nozzle  40  is exposed will be described as a “nozzle surface”. The recording head  39  discharges ink from the nozzle  40  as a minute ink droplet. In a process of the carriage  23  moving, the recording head  39  discharges the ink droplet toward the sheet  12  supported by the platen  42 . Moreover, as a result, ink stored in the ink tanks  100 B,  100 Y,  100 C,  100 M is consumed. 
     The printer unit  11  includes a maintenance mechanism (not illustrated). The maintenance mechanism performs maintenance of the recording head  39 . In detail, the maintenance mechanism executes a purge operation that sucks up ink or air in the nozzle  40  or a removal operation that removes foreign matter, and so on, adhered to the nozzle surface. The maintenance mechanism sends forth ink sucked up from the nozzle  40  of the recording head  39  to a waste ink tank (not illustrated), via a tube (not illustrated). The maintenance mechanism is disposed directly below the carriage  23  positioned more rightward or leftward than the conveyance passage  65 . 
     Before the purge operation is executed, the carriage  23  moves to directly above the maintenance mechanism. Then, a cap (not illustrated) of the maintenance mechanism moves upwardly to cover the nozzle surface. The cap is connected to the waste ink tank via the tube. A rotary-type tube pump is disposed in the tube. Driving of the tube pump causes inside the tube to become a vacuum. As a result, ink in the recording head  39  is sucked up. The sucked up ink is discharged to the waste ink tank via the cap and the tube. 
     Note that the tube is in a state of being blocked by the rotary-type tube pump in at least one place. 
     Platen  42   
     As depicted in  FIGS. 2 and 3 , the platen  42  is disposed between the conveyance roller unit  54  and the discharge roller unit  55 , in relation to the conveyance orientation  16 . The platen  42  is disposed so as to face the recording unit  24  in the up-down direction  7 , sandwiching the conveyance passage  65  between itself and the recording unit  24 . The platen  42  supports, from below, the sheet  12  conveyed by the conveyance roller unit  54 . 
     Tank Set  99   
     The tank set  99  stores the ink supplied to the recording head  39 . As depicted in  FIGS. 1A and 1B , the tank set  99  includes the four ink tanks  100 B,  100 Y,  100 C,  100 M. A different color of ink is respectively stored in each of the four ink tanks  100 B,  100 Y,  100 C,  100 M. Specifically, black ink is stored in the ink tank  100 B, yellow ink is stored in the ink tank  100 Y, cyan ink is stored in the ink tank  100 C, and magenta ink is stored in the ink tank  100 M. However, the number of ink tanks  100  and colors of the inks are not limited to the above-described example. 
     The four ink tanks  100 B,  100 Y,  100 C,  100 M are disposed in line along the left-right direction  9 . Of the four ink tanks  100 B,  100 Y,  100 C,  100 M, the ink tank  100 B is disposed most rightwards, and the ink tank  100 M is disposed most leftwards. Note that arrangement positions of the ink tanks  100  are not limited to the above-described example. The black ink-dedicated ink tank  100 B has a size, particularly a width in the left-right direction  9  which is larger than those of the color ink-dedicated ink tanks  100 Y,  100 C,  100 M. Note that a magnitude relationship of sizes of the ink tanks  100  is not limited to the above-described example. The ink tank  100 B has a permissible storage amount of ink which is larger than those of the other ink tanks  100 Y,  100 C,  100 M. Note that a magnitude relationship of permissible storage amounts of the ink tanks  100  is not limited to the above-described example. 
     As depicted in  FIGS. 1A and 1B , the tank set  99  is installed in a right front section of the casing  14 . In other words, the tank set  99  is fixed to the multifunction peripheral  10  such that it cannot be easily removed from the multifunction peripheral  10 . Note that “cannot be easily removed” means, for example, that the user cannot easily remove the tank set  99  from the casing  14  of the multifunction peripheral  10  in a state of ordinary use, and excludes cases such as when a skilled repairer removes the tank set  99  from the casing  14  of the multifunction peripheral  10  for repair. Therefore, the user should not be able to easily remove the tank set  99  from the casing  14  of the multifunction peripheral  10  in a state of ordinary use. 
     A front surface of each of the ink tanks  100  is exposed to the outside of the multifunction peripheral  10  via an opening  22  formed in a right section of the front wall  14 A of the casing  14 . The opening  22  is adjacent in the left-right direction  9  to the opening  13 . The casing  14  is provided with a cover  70 . The cover  70  is pivotable between a closed position where the opening  22  is covered (position depicted in  FIG. 1A ) and an open position where the opening  22  is exposed (position depicted in  FIG. 1B ). The cover  70  has a pivot shaft (not illustrated) extending in the left-right direction  9  in a vicinity of a lower end in the up-down direction  7  of the cover  70 , and is supported by the casing  14  so as to pivot around a pivotal axis  70 A of the pivot shaft. 
     Configurations of the ink tanks  100  will be described in detail below. Since configurations of the color ink-dedicated ink tanks  100 Y,  100 C,  100 M are the same, hereafter, one of the ink tanks  100 Y,  100 C,  100 M will be referred to as the ink tank  100  and its configuration will be described. Moreover, a configuration of the black ink-dedicated ink tank  100 B is similar to the configuration of the ink tanks  100 Y,  100 C,  100 M, hence after the configuration of the ink tanks  100 Y,  100 C,  100 M has been described, the configuration of the ink tank  100 B will be described for portions different from in the ink tanks  100 Y,  100 C,  100 M. In this case, configurations having a similar function even though shapes somewhat differ in the configurations of the ink tank  100 B and the ink tanks  100 Y,  100 C,  100 M, will be assigned with identical reference symbols. Note that in the description below, unless specifically stated otherwise, the multifunction peripheral  10  and the ink tank  100  installed in the multifunction peripheral  10  are in the usable posture. 
     Ink Tank  100   
     As depicted in  FIGS. 4 and 5 , the ink tank  100  is configured by a casing  140  forming an outer shape of the ink tank. The casing  140  includes a frame  141  and two films  142 ,  143  (examples of a first film and a second film). 
     The frame  141  has a flat rectangular parallelepiped shape in which a dimension in the left-right direction  9  is short and dimensions in each of the up-down direction  7  and the front-rear direction  8  are longer than the dimension in the left-right direction  9 . Moreover, the dimension in the front-rear direction  8  is longer than the dimension in the up-down direction  7 . In other words, the ink tank  100  has a first side along the front-rear direction  8 , a second side along the up-down direction  7  which is shorter than said first side, and a third side along the left-right direction  9  which is shorter than said second side. 
     The frame  141  is formed by a resin having sufficient translucency to enable ink in a later-mentioned ink chamber  111  to be visually confirmed from the outside of the ink tank  100 . The frame  141  is formed by, for example, polypropylene. The frame  141  is integrally molded by, for example, injection molding a resin material. Rigidity of the frame  141  is higher than rigidity of the films  142 ,  143 . 
     Note that the frame  141  may be configured by a material other than a resin. Moreover, the frame  141  may have a configuration in which a plurality of members is combined. For example, it is possible for a later-mentioned first ink chamber  131  and second ink chamber  132  to be respectively configured by two separate casings, and for these two casings to be joined by a tube, or the like. 
     The frame  141  includes a front wall  101 , a left wall  103 , an upper wall  104 , a lower wall  105 , a rear wall  110 , and inner walls  69 ,  71 - 79 ,  151 - 155 . 
     The front wall  101  is configured by an upright wall  102  and an inclined wall  106 . The upright wall  102  extends in the up-down direction  7  and the left-right direction  9 . The inclined wall  106  is a wall joining an upper end of the upright wall  102  and a front end of the upper wall  104 , and inclines in the up-down direction  7  and the front-rear direction  8 . 
     The left wall  103  is a wall extending rearwards from a left end of the front wall  101 . An upper end of the left wall  103  is connected to a front section of the upper wall  104 . A lower end of the left wall  103  is connected to a front section of the lower wall  105 . In other words, the left wall  103  is a wall joining the left end of the front wall  101 , a left end of the front section of the upper wall  104 , and a left end of the front section of the lower wall  105 . In other words, the left wall  103  is provided only in a front section of the frame  141  and is not provided in a rear section of the frame  141 . 
     The upper wall  104  extends rearwards from an upper end of the front wall  101  (rear end of the inclined wall  106 ). The front section of the upper wall  104  is connected to the upper end of the left wall  103 . A protrusion  144  protruding upwardly is formed roughly from a central section to a rear section in the front-rear direction  8  of the upper wall  104 . The protrusion  144  includes: a front wall  144 A protruding upwardly from roughly the central section in the front-rear direction  8  of the upper wall  104 ; a rear wall  144 B protruding upwardly from the rear section of the upper wall  104 ; and an upper wall  144 C joining an upper end of the front wall  144 A and an upper end of the rear wall  144 B. 
     The lower wall  105  is a wall extending rearwards from a lower end of the front wall  101 . The lower wall  105  is formed separated downwardly from the upper wall  104 . As mentioned above, the front section of the lower wall  105  is connected to the lower end of the left wall  103 . A left end section of the lower wall  105  is bent upwardly. An upper end of the bent lower wall  105  is connected to a lower surface of the later-mentioned inner wall  72  (refer to  FIG. 5 ). 
     The rear wall  110  is formed separated rearwards from the front wall  101 . As mentioned above, the upper end of the rear wall  110  is connected to the rear end of the upper wall  104 . The lower end of the rear wall  110  is connected to the rear end of the lower wall  105 . A left section of the rear wall  110  is positioned more rearwards than a right section of the rear wall  110 . A later-mentioned ink outflow passage  114  is formed in the left section of the rear wall  110 . 
     As depicted in  FIGS. 6 and 7 , the inner wall  71  extends downwardly from the upper wall  104  and the upper wall  144 C of the protrusion  144 . The inner wall  71  is a wall extending in the up-down direction  7  and the front-rear direction  8 . The inner wall  71  is provided in a range of hatching depicted in  FIGS. 6 and 7 . The inner wall  71  is provided at any position between a right end and a left end of the frame  141 , in relation to the left-right direction  9 . For example, the inner wall  71  is provided roughly in a central section of the frame  141 , in relation to the left-right direction  9 . As a result, the inside of the frame  141  is divided into left and right at a place where the inner wall  71  is provided. Moreover, the inner wall  71  may be provided at a position close to the right end of the frame  141  or a position close to the left end of the frame  141 , in relation to the left-right direction  9 . Note that the inner wall  71  defines part of a later-mentioned communicating path, hence is desirably provided at a position not including the right end and the left end of the frame  141 . 
     As depicted in  FIGS. 4 and 5 , the inner wall  72  is provided in a vicinity of the lower wall  105  between the upper wall  104  and the lower wall  105 , in relation to the up-down direction  7 . The inner wall  72  extends rearwards while inclining upwards, from the front end section to the rear end section of the lower wall  105 . A front end of the inner wall  72  is connected to a part on a front end section side of the lower wall  105 . A rear end of the inner wall  72  is positioned separated from the rear wall  110 , frontwards of the rear wall  110 . 
     The inner wall  73  extends roughly upwardly from the rear end of the inner wall  72 , while maintaining constant a spacing from the rear wall  110 . The inner wall  73  extends to the inside of the protrusion  144  while bending so as to follow an outer shape of the protrusion  144 . An upper end of the inner wall  73  is positioned separated from the upper wall  144 C of the protrusion  144 , downwardly of the upper wall  144 C. Part of the inner wall  73  (a portion more downward than the later-mentioned inner wall  75 ) extends from the right end to the left end of the frame  141 . On the other hand, another portion of the inner wall  73  extends from the right end of the frame  141  to the inner wall  71 . 
     The inner wall  69  extends in the up-down direction  7  and the front-rear direction  8 . The inner wall  69  is positioned between the inner wall  72  and the later-mentioned inner wall  75  in relation to the up-down direction  7 . The inner wall  69  is positioned frontwards of the inner wall  73 . The inner wall  69  is provided roughly in the central section of the frame  141  in relation to the left-right direction  9 . As a result, a later-mentioned rear ink chamber  138  of the first ink chamber  131  is divided into left and right at a place where the inner wall  69  is provided. A lower end of the inner wall  69  is connected to a rear section of the inner wall  72 . An upper end of the inner wall  69  is connected to a rear section of the inner wall  75 . A rear end of the inner wall  69  is connected to the inner wall  73 . 
     The inner walls  74 - 77  described below extend rightwards from the inner wall  71  (refer to  FIG. 6 ). In other words, the inner walls  74 - 77  extend from the inner wall  71  to the right end of the frame  141 . 
     As depicted in  FIGS. 4 to 6 , the inner wall  74  extends downwardly in a front section of a lower surface  104 A of the upper wall  104 . A left end of the inner wall  74  is connected to the left wall  103 , and a rear surface of the inner wall  74  is connected to a front end of the inner wall  71 . 
     The inner wall  75  extends rearwards from a lower end of the inner wall  74 . A rear end of the inner wall  75  is connected to the inner wall  73 . 
     The inner wall  76  extends frontwards from an upper end of the inner wall  73 . In other words, the inner wall  76  is positioned more upwardly than the inner wall  75 . A front end of the inner wall  76  is positioned more rearwards than a later-mentioned through hole  175 . 
     The inner wall  77  extends rearwards from a lower end of the front wall  144 A of the protrusion  144 . A front section of the inner wall  77  is positioned between the upper wall  144 C of the protrusion  144  and the inner wall  75 , in relation to the up-down direction  7 , and faces, in the up-down direction  7 , the upper wall  144 C of the protrusion  144  and the inner wall  75 . A rear section of the inner wall  77  is positioned between the inner wall  76  and the inner wall  75  in relation to the up-down direction  7 , and faces, in the up-down direction  7 , the inner wall  76  and the inner wall  75 . A rear end of the inner wall  77  is positioned separated from the inner wall  73 , frontwards of the inner wall  73 . 
     The inner walls  78 ,  79  described below extend rightwards and leftwards from the inner wall  71  (refer to  FIGS. 6 and 7 ). In other words, the inner walls  78 ,  79  extend from the right end to the left end of the frame  141 . 
     As depicted in  FIGS. 4 and 5 , the inner wall  78  extends in the up-down direction  7  and the left-right direction  9 . The inner wall  78  is provided separated from the front wall  144 A rearwards of the front wall  144 A of the protrusion  144 . As depicted in  FIG. 6 , the inner wall  78  faces the inner wall  76 , sandwiching the through hole  175  between itself and the inner wall  76 , in relation to the front-rear direction  8 . In other words, the inner wall  78  is provided between the front wall  144 A and the through hole  175 , in relation to the front-rear direction  8 . 
     The inner wall  79  extends in the up-down direction  7  and the left-right direction  9 . The inner wall  79  is positioned more rearwards than the inner wall  74  and more frontwards than the inner wall  69 . An upper end of the inner wall  79  is connected to the inner wall  75 . A lower end of the inner wall  79  is connected to the inner wall  72 . A left end of the inner wall  79  is connected to the left wall  103 . 
     The inner walls  151 ,  152  described below extend leftwards from the inner wall  71  (refer to  FIG. 7 ). In other words, the inner walls  151 ,  152  extend from the inner wall  71  to the left end of the frame  141 . 
     As depicted in  FIGS. 5 and 7 , the inner wall  151  is a wall joining the lower end of the front wall  144 A of the protrusion  144  and a rear section of the upper wall  144 C of the protrusion  144 . The inner wall  151  extends rearwards from the lower end of the front wall  144 A, then extends upwardly, then extends rearwards, and then extends upwardly to reach the upper wall  144 C. 
     The inner wall  152  is a wall joining two places of the upper wall  144 C of the protrusion  144 . Said two places are a front end section of the upper wall  144 C and a central section in the front-rear direction  8  of the upper wall  144 C. The inner wall  152  extends downwardly from a lower surface of the front end section of the upper wall  144 C, then extends rearwards, and then extends upwardly to reach a lower surface of the central section in the front-rear direction  8  of the upper wall  144 C. The inner wall  152  is surrounded by the upper wall  144 C and the inner wall  151 , when the ink tank  100  is viewed from the left. 
     As depicted in  FIG. 4 , a right surface of the frame  141  is open. The film  142  is welded to right surfaces of the front wall  101 , the lower wall  105 , the rear wall  110 , the upper wall  104 , the inner walls  72 - 79 , the front wall  144 A of the protrusion  144 , the rear wall  144 B of the protrusion  144 , and the upper wall  144 C of the protrusion  144 , whereby the right surface of the frame  141  is sealed. 
     As depicted in  FIG. 5 , a rear section of a left surface of the frame  141  is open. The film  143  is welded to left surfaces of the rear wall  110 , the upper wall  104 , the inner wall  72 , the inner wall  79 , the inner wall  151 , the inner wall  152 , the front wall  144 A of the protrusion  144 , the rear wall  144 B of the protrusion  144 , the upper wall  144 C of the protrusion  144 , and a later-mentioned separating wall  186 , whereby the left surface of the frame  141  is sealed. 
     As depicted in  FIG. 4 , an outer surface (front surface) of the upright wall  102  of the front wall  101  includes a first line  146  and a second line  147 . 
     The first line  146  extends in the left-right direction  9 . A position in the up-down direction  7  of the first line  146  is at the same height as a liquid surface of the ink when a maximum permissible amount (an example of a first amount) of ink has been stored in the ink chamber  111 , with the multifunction peripheral  10  in the usable posture. Note that the position in the up-down direction  7  of the first line  146  is not limited to being at the same height as the liquid surface of the ink when said maximum amount of ink has been stored in the ink chamber  111 . 
     The second line  147  extends in the left-right direction  9 . The second line  147  is positioned more downwardly than the first line  146 . In detail, a position in the up-down direction  7  of the second line  147  is at the same height as a liquid surface of the ink when an amount (an example of a second amount) less than the above-described maximum amount of ink has been stored in the ink chamber  111 , with the multifunction peripheral  10  in the usable posture. In the present embodiment, the position in the up-down direction  7  of the second line  147  is at the same height as a liquid surface of the ink when ink of a minimum storage amount at which replenishment of ink becomes required, has been stored in the ink chamber  111 , with the ink tank  100  in the usable posture. 
     Ink Chamber  111   
     As depicted in  FIGS. 4 and 5 , the ink chamber  111  (an example of a liquid storage chamber) is formed on the inside of the casing  140 . The ink chamber  111  is an internal space of the ink tank  100 , and has ink stored therein. The ink chamber  111  includes the first ink chamber  131  and the second ink chamber  132 . 
     The first ink chamber  131  includes: a space described below; and a first communicating path  171  of an atmosphere communication passage communicated with said space. The second ink chamber  132  includes: a space described below; a second communicating path  172  of the atmosphere communication passage communicated with said space; a buffer chamber  148 ; and the ink outflow passage  114 . The atmosphere communication passage, the buffer chamber  148 , and the ink outflow passage  114  will be mentioned later. 
     The first ink chamber  131  is demarcated by the front wall  101 , the left wall  103 , the lower wall  105 , the rear wall  110 , the inner wall  72 , the inner wall  73 , the inner wall  74 , the inner wall  75 , the upper wall  104 , the inner wall  151 , the upper wall  144 C of the protrusion  144 , the film  142 , and the film  143 . The front wall  101  demarcates a front surface of the first ink chamber  131 . The lower wall  105  and the inner wall  72  demarcate a lower surface of the first ink chamber  131 . The inner wall  73  demarcates a rear surface of the first ink chamber  131 . The inner wall  75 , the inner wall  74 , and the upper wall  104  demarcate an upper surface of the first ink chamber  131 . The film  142  demarcates a right surface of the first ink chamber  131 . The left wall  103  and the film  143  demarcate a left surface of the first ink chamber  131 . 
     The first ink chamber  131  is divided into a front ink chamber  137  and the rear ink chamber  138 , by the inner wall  79 . A front surface of the inner wall  79  demarcates a rear surface of the front ink chamber  137 . A rear surface of the inner wall  79  demarcates a front surface of the rear ink chamber  138 . 
     An upper end section of the inner wall  79  is cut out leftwards from a right end. As a result, an opening  135  is formed in the upper end section of the inner wall  79 . The opening  135  is demarcated by the inner wall  79 , the inner wall  75 , and the film  142 . A lower end section of the inner wall  79  is cut out leftwards from a right end. As a result, an opening  136  is formed in the lower end section of the inner wall  79 . The opening  136  is demarcated by the inner wall  79 , the inner wall  72 , and the film  142 . The front ink chamber  137  and the rear ink chamber  138  communicate by the openings  135 ,  136 . 
     As depicted in  FIGS. 4 and 6 , the second ink chamber  132  is positioned downwardly and rearwards of the first ink chamber  131 . The second ink chamber  132  has roughly an L shape, when the ink tank  100  is viewed from the left. The second ink chamber  132  includes a lower ink chamber  51  and an upper ink chamber  52 . The lower ink chamber  51  is positioned downwardly of the first ink chamber  131 . The upper ink chamber  52  extends upwardly from a rear end section of the lower ink chamber  51 . The upper ink chamber  52  is positioned rearwards of the rear ink chamber  138  of the first ink chamber  131 . 
     The lower ink chamber  51  is demarcated by the lower wall  105 , the inner wall  72 , and the film  142 . The lower wall  105  demarcates a front surface, a lower surface, and a left surface of the lower ink chamber  51 . The inner wall  72  demarcates an upper surface of the lower ink chamber  51 . The film  142  demarcates a right surface of the lower ink chamber  51 . A rear end of the lower ink chamber  51  is open. The lower ink chamber  51  communicates with the upper ink chamber  52  at said rear end. 
     A front end section of the inner wall  72  is cut out leftwards from a right end. As a result, an opening  145  is formed in the front end section of the inner wall  72 . The opening  145  is demarcated by the inner wall  72 , the lower wall  105 , and the film  142 . The front ink chamber  137  of the first ink chamber  131  and the lower ink chamber  51  of the second ink chamber  132  communicate by the opening  145 . 
     The upper ink chamber  52  is demarcated by the rear wall  110 , the inner wall  73 , and the film  142 . The rear wall  110  demarcates a rear surface and a left surface of the upper ink chamber  52 . The inner wall  73  demarcates a front surface of the upper ink chamber  52 . The film  142  demarcates a right surface of the upper ink chamber  52 . A lower end of the upper ink chamber  52  is open. The upper ink chamber  52  communicates with the lower ink chamber  51  at said lower end. 
     An upper end of the upper ink chamber  52  is open. Now, said upper end is at the same height as the first line  146 . In other words, said upper end is at the same height as a liquid surface of the ink when a maximum permissible amount of ink has been stored in the ink chamber  111 , with the multifunction peripheral  10  in the usable posture. Moreover, the upper ink chamber  52  communicates with the later-mentioned second communicating path  172  of the atmosphere communication passage, at said upper end. That is, said upper end is a boundary of the upper ink chamber  52  and the second communicating path  172 . Note that said boundary is not limited to the previously mentioned position, and may be more upward or downward than the first line  146 , for example. 
     As described above, a right surface (an example of a first surface) of the ink chamber  111  is demarcated by a left surface  142 L of the film  142  (refer to  FIG. 12A ). In other words, all of the right surface of the ink chamber  111  is configured by the film  142 . 
     Moreover, a left surface (an example of a second surface) of the ink chamber  111  is demarcated by a right surface  143 R of the film  143  and a right surface  103 R of the left wall  103  (refer to  FIG. 12A ). In other words, part of the left surface of the ink chamber  111  is configured by the film  143 . 
     Note that the right surface of the ink chamber  111  may be demarcated by the film  142  and a wall. In other words, it is possible for part of the right surface of the ink chamber  111  to be configured by the film  142 . Moreover, the left surface of the ink chamber  111  may be demarcated by the film  143  only. In other words, it is possible for all of the left surface of the ink chamber  111  to be configured by the film  143 . 
     Moreover, the right surface and the left surface of the ink chamber  111  do not need to be flush. For example, as depicted in  FIG. 12A , in a state where the film  143  has been welded, the right surface  143 R of the film  143  is positioned more leftwards than the right surface  103 R of the left wall  103 . In other words, there is a level difference between the right surface  143 R of the film  143  and the right surface  103 R of the left wall  103 . Even in this case, the second surface is configured by the right surface  143 R of the film  143  and the right surface  103 R of the left wall  103 . In other words, the second surface is configured by a plurality of plane surfaces having level differences. 
     The right surface and the left surface of the ink chamber  111  face each other in a state of being separated from each other. In other words, the right surface and the left surface of the ink chamber  111  are surfaces that face each other. 
     In the present embodiment, a part of the film  142  configuring the right surface of the ink chamber  111  and a part of the film  143  configuring the left surface of the ink chamber  111 , of the right surface and the left surface of the ink chamber  111 , face each other. 
     Specifically, as depicted in  FIG. 12A , a portion more rearward than the inner wall  79  and more frontward than the inner wall  69  of the film  142  and a portion more frontward than the inner wall  69  of the film  143  face each other without another member interposing between them. In other words, a central section  142 A in the front-rear direction  8  of the film  142  and a central section  143 A in the front-rear direction  8  of the film  143  face each other without another member interposing between them. 
     Moreover, a rear section  142 B of the film  142  and a rear section  143 B of the film  143  face each other in a state that the inner wall  69  interposes between them. 
     Note that what faces a front section  142 C of the film  142  in the left surface of the ink chamber  111  is the left wall  103 , not the film  143 . In other words, the front section  142 C of the film  142  does not face the film  143 . 
     From the above, part of the film  142  and part of the film  143  facing means fellow films are facing. 
     The right surface and the left surface of the ink chamber  111  are both surfaces extending in the front-rear direction  8  and the up-down direction  7 . In other words, the right surface and the left surface of the ink chamber  111  each have the first side along the front-rear direction  8  and the second side along the up-down direction  7 . Moreover, since the right surface and the left surface of the ink chamber  111  are both surfaces extending in the front-rear direction  8  and the up-down direction  7 , the right surface and the left surface of the ink chamber  111  are parallel. Note that the right surface and the left surface of the ink chamber  111  need not be parallel. For example, the right surface of the ink chamber  111  may be a surface inclined with respect to the left surface of the ink chamber  111 . 
     A liquid surface of the ink when the maximum permissible amount of ink is stored in the ink chamber  111  in the usable posture of the multifunction peripheral  10 , in other words, in a state where the upper wall  104  is positioned in an upper section of the ink tank  100  and the lower wall  105  is positioned in a lower section of the ink tank  100 , is depicted by the broken line  191  of  FIG. 6 . In other words, the liquid surface of the ink is at the same height as the first line  146 , as mentioned above. 
     At this time, a height in the vertical direction (a height in the up-down direction  7 ) of a liquid surface of ink stored in the first ink chamber  131  and a height in the vertical direction (a height in the up-down direction  7 ) of a liquid surface of ink stored in the second ink chamber  132  are the same. 
     Moreover, at this time, the liquid surface of ink in the first ink chamber  131  and the liquid surface of ink in the second ink chamber  132  are formed independently of each other. Specifically, the liquid surface of ink in the first ink chamber  131  is surrounded by the front wall  101 , the inner wall  73 , the film  142 , the left wall  103 , and the film  143 . On the other hand, the liquid surface of ink in the second ink chamber  132  is surrounded by the rear wall  110 , the inner wall  73 , and the film  142 . 
     Note that the liquid surface of ink in the first ink chamber  131  and the liquid surface of ink in the second ink chamber  132  being formed independently of each other is not limited to when the maximum permissible amount of ink is stored in the ink chamber  111 . For example, the liquid surface of ink in the first ink chamber  131  and the liquid surface of ink in the second ink chamber  132  being formed independently of each other may be when the liquid surface of ink stored in the ink chamber  111  attains the same height as the second line  147 . Of course, the liquid surface of ink in the first ink chamber  131  and the liquid surface of ink in the second ink chamber  132  may be formed independently of each other when the maximum permissible amount of ink is stored in the ink chamber  111 , when the liquid surface of ink stored in the ink chamber  111  attains the same height as the second line  147 , and/or when another amount of ink is stored. 
     Moreover, the liquid surface of ink in the first ink chamber  131  and the liquid surface of ink in the second ink chamber  132  may be formed independently of each other, even when the multifunction peripheral  10  is not in the usable posture. 
     For example, a position of the liquid surface of the ink when the maximum permissible amount of ink is stored in the ink chamber  111 , in a state where the lower wall  105  is positioned in the upper section of the ink tank  100  and the upper wall  104  is positioned in the lower section of the ink tank  100 , is depicted by the broken line  192  of  FIG. 6 . That is, the liquid surface of the ink is at the position of the broken line  192  depicted between the first line  146  and the second line  147 , in the up-down direction  7 . 
     Moreover, for example, the position of the liquid surface of the ink when the maximum permissible amount of ink is stored in the ink chamber  111 , in a state where the front wall  101  is positioned in the upper section of the ink tank  100  and the rear wall  110  is positioned in the lower section of the ink tank  100 , is depicted by the one dot-chain line  193  of  FIG. 6 . 
     Moreover, for example, the position of the liquid surface of the ink when the maximum permissible amount of ink is stored in the ink chamber  111 , in a state where the rear wall  110  is positioned in the upper section of the ink tank  100  and the front wall  101  is positioned in the lower section of the ink tank  100 , is depicted by the two dot-chain line  194  of  FIG. 6 . 
     When the maximum permissible amount of ink is stored in the ink chamber  111 , in the usable posture of the multifunction peripheral  10 , a length (hereafter referred to as a “first length”) of a portion demarcated by the film  142  or  143  of an outer edge of the liquid surface of the ink stored in the ink chamber  111  is longer than a length (hereafter referred to as a “second length”) of a portion not demarcated by either the film  142  or the film  143  of said outer edge of the liquid surface of the ink, in other words of a portion demarcated by a wall of said outer edge of the liquid surface of the ink. At this time, the wall refers to a surface demarcating the ink chamber  111 . That is, the inner wall  69  or the inner wall  73  or the inner wall  79  of  FIG. 13  is not included. Specifically, as depicted in  FIG. 13 , the first length is A 1 +A 2 +A 3 +A 4 , and the second length is B 1 +B 2 +B 3 +B 4 . Moreover, A 1 +A 2 +A 3 +A 4  is longer than B 1 +B 2 +B 3 +B 4 . 
     When a plurality of ink chambers are provided in the ink tank  100 , a similar effect can be displayed, provided the above-mentioned kind of relationship holds in one ink chamber (for example, the first ink chamber  131 ), not in the ink chamber  111  overall. For example, when the maximum permissible amount of ink is stored in the first ink chamber  131 , in the usable posture of the multifunction peripheral  10 , a length (referred to as a “first length” similarly to as mentioned above) of a portion demarcated by the film  142  or the film  143  of an outer edge of the liquid surface of ink stored in the first ink chamber  131  is longer than a length (referred to as a “second length” similarly to as mentioned above) of a portion not demarcated by either the film  142  or the film  143  of said outer edge of the liquid surface of the ink, in other words of a portion demarcated by a wall of said outer edge of the liquid surface of the ink. At this time, the wall refers to a surface demarcating the first ink chamber  131 . That is, the inner wall  69  or the inner wall  79  of  FIG. 13  is not included. Specifically, as depicted in  FIG. 13 , the first length is A 1 +A 2 +A 4 , and the second length is B 1 +B 2 +B 4 . Moreover, A 1 +A 2 +A 4  is longer than B 1 +B 2 +B 4 . 
     In the present embodiment, when the liquid surface of ink is between the first line  146  and the second line  147 , the first length is longer than the second length. Note that between the first line  146  and the second line  147  includes the case where the liquid surface of ink is the same as the first line  146  and the case where the liquid surface of ink is the same as the second line  147 . 
     Note that a condition of the first length being longer than the second length need only be satisfied in at least one state that the liquid surface of ink is positioned between the first line  146  and the second line  147 . For example, if the above-described condition is satisfied when the liquid surface of ink is higher than an intermediate line between the first line  146  and the second line  147 , the above-described condition need not be satisfied when the liquid surface of ink is lower than said intermediate line. 
     Buffer Chamber  148   
     As depicted in  FIGS. 4 and 6 , the buffer chamber  148  is formed on the inside of the casing  140 . The buffer chamber  148  is an internal space of the ink tank  100  and interposes between the second ink chamber  132  and the later-mentioned ink outflow passage  114 . In other words, ink stored in the second ink chamber  132  flows into the ink outflow passage  114  via the buffer chamber  148 . 
     The buffer chamber  148  is provided on a right side of a rear lower section of the casing  140 . The buffer chamber  148  is demarcated by an inner wall  153 , an inner wall  154 , an inner wall  155 , the lower wall  105 , the rear wall  110 , and the film  142 . 
     The inner wall  153  protrudes frontwards from a front surface in a right lower section of the rear wall  110  and extends in the left-right direction  9 . The inner wall  153  demarcates an upper surface of the buffer chamber  148 . The inner wall  154  protrudes upwardly from an upper surface in a right rear section of the lower wall  105  and extends in the left-right direction  9 . The inner wall  154  demarcates a front surface of the buffer chamber  148 . The inner wall  155  is a wall extending in the up-down direction  7  and the front-rear direction  8 , and is surrounded by the inner wall  153 , the inner wall  154 , the rear wall  110 , and the lower wall  105 . The inner wall  155  demarcates a left surface of the buffer chamber  148 . The lower wall  105  demarcates a lower surface of the buffer chamber  148 . The rear wall  110  demarcates a rear surface of the buffer chamber  148 . The film  142  demarcates a right surface of the buffer chamber  148 . 
     A right lower end section of the inner wall  154  is cut out leftwards from a right end. As a result, an opening  149  is formed in the right lower end section of the inner wall  154 . The opening  149  is demarcated by the inner wall  154  and the film  142 . The opening  149  communicates a right side of a rear lower section of the second ink chamber  132  and the buffer chamber  148 . Note that in the present embodiment, the inner wall  154  is cut out in a semicircular shape, but a shape of a cut-out is not limited to a semicircular shape, and may be a rectangular shape, for example. 
     A circular-shaped opening  150  is formed in a central section of the inner wall  155 . The opening  150  communicates the buffer  148  and the ink outflow passage  114 . Ink stored in the second ink chamber  132  flows into the opening  150  via the buffer chamber  148 . In other words, the opening  150  is an ink inflow port (an example of a liquid inflow port) for ink to flow from the buffer chamber  148  into the ink outflow passage  114 . Note that a shape of the opening  150  is not limited to a circular shape, and may be the likes of a rectangular shape, for example. 
     Ink Outflow Passage  114   
     As depicted in  FIGS. 5 and 7 , the casing  140  includes the ink outflow passage  114 . The ink outflow passage  114  is a communicating path for ink stored in the second ink chamber  132  to flow out to outside of the ink tank  100 . Note that in the present embodiment, since ink stored in the first ink chamber  131  moves to the second ink chamber  132  via the opening  145 , it could also be said that the ink outflow passage  114  is a communicating path for ink stored in the first ink chamber  131  and the second ink chamber  132  to flow out to outside of the ink tank  100 . 
     The ink outflow passage  114  communicates with the buffer chamber  148  via the opening  150 . The ink outflow passage  114  extends leftwards from the opening  150 , then extends upwardly, then extends downwardly, and then extends rightwards to reach an opening  156 . 
     The ink outflow passage  114  is formed as a trench recessed rightwards from a left surface of the rear wall  110 . A portion excluding a left surface and part of a right surface of the ink outflow passage  114  is demarcated by the rear wall  110 . A peripheral portion of the opening  156  in the right surface of the ink outflow passage  114  is demarcated by the inner wall  155 . The left surface of the ink outflow passage  114  is demarcated by the film  143 . 
     The frame  141  includes a tubular protrusion  157 . The protrusion  157  protrudes rearwards from the peripheral portion of the opening  156  of the rear wall  110 . A front end of an internal space of the protrusion  157  communicates with the ink outflow passage  114  via the opening  156 . A rear end of the internal space of the protrusion  157  communicates with outside of the ink tank  100  by an opening  158  (an example of a liquid outflow port). The ink tube  32  is connected to the protrusion  157  via the opening  158 . 
     As described above, one end of the ink outflow passage  114  communicates with the second ink chamber  132  via the buffer chamber  148 . Moreover, the other end of the ink outflow passage  114  communicates with the nozzle  40  of the recording head  39  via the internal space of the protrusion  157  and the ink tube  32 . In other words, ink that has flowed in from the opening  150  flows out from the opening  158  toward the recording head  39 . Moreover, when ink is consumed by ink droplets being discharged from the recording head  39 , ink in the ink outflow passage  114  moves toward the recording head  39 . 
     Now, the ink outflow passage  114  is a flow path. The flow path refers to a space whose one end is connected to the ink chamber  111  and into which, when its other end is blocked, ink stored in the ink chamber  111  does not flow regardless of posture of the ink tank  100 . In the present embodiment, the ink tank  100  includes only the ink outflow passage  114  as a flow path, but may include a flow path other than the ink outflow passage  114 . 
     As mentioned above, the tube extending from the cap of the maintenance mechanism capable of covering the nozzle  40  of the recording head  39  is blocked by the pump. Hence, when the nozzle  40  is covered by the cap, the other end (an end on a protrusion  157  side) of the ink outflow passage  114  communicates with the blocked tube via the internal space of the protrusion  157 , the ink tube  132 , the recording head  39 , and the cap. In other words, the other end of the ink outflow passage  114  is blocked. Moreover, a cross-sectional area of the ink outflow passage  114  is configured to be sufficiently smaller compared to a cross-sectional area of the second ink chamber  132 . Therefore, even if the ink tank  100  is in a posture other than the usable posture, in other words, regardless of the posture of the ink tank  100 , ink stored in the second ink chamber  132  never flows into the ink outflow passage  114 . Note that when the nozzle  40  is not covered by the cap, the nozzle  40  is open. In other words, the other end of the ink outflow passage  114  is open. Therefore, ink stored in the second ink chamber  132  can flow into the ink outflow passage  114 . 
     On the other hand, the above-mentioned opening  145  and the later-mentioned atmosphere communication passage are a boundary. The boundary refers to a space at least one of whose one end or other end is connected to the ink chamber  111  and into which ink stored in the ink chamber  111  can flow even supposing the one end or the other end is blocked. In the present embodiment, the ink tank  100  includes only the opening  145  and the atmosphere communication passage as a boundary, but may include a boundary other than the opening  145  and the atmosphere communication passage. 
     Atmosphere Communication Passage 
     As depicted in  FIGS. 4 to 7 , the casing  140  includes the atmosphere communication passage. The atmosphere communication passage is a communicating path for communicating the ink chamber  111  and outside of the ink tank  100 . In other words, the atmosphere communication passage is a communicating path for opening the ink chamber  111  to the air. The atmosphere communication passage includes: the first communicating path  171  and the second communicating path  172  depicted in  FIGS. 4 and 6 ; and a third communicating path  173  depicted in  FIGS. 4 to 7 . The first communicating path  171  and the second communicating path  172  are positioned more rightwards than the inner wall  71 . The third communicating path  173  is positioned both rightwards and leftwards of the inner wall  71 . 
     As depicted in  FIGS. 4 and 6 , the first communicating path  171  communicates with the front ink chamber  137  of the first ink chamber  131  via an opening  174 . The opening  174  is formed by a right front end section of the inner wall  75  being cut out leftwards from a right end. The opening  174  is demarcated by the inner wall  75 , the inner wall  74 , and the film  142 . 
     The first communicating path  171  extends rearwards from the opening  174 , and then extends frontwards making a U-turn to reach the through hole  175  (refer to  FIGS. 6  and  7 ). The through hole  175  is provided in the inner wall  71 . The through hole  175  is provided somewhat more frontwards than a center of the protrusion  144 , in relation to the front-rear direction  8 . The through hole  175  communicates with rightward and leftward of the inner wall  71 . 
     The first communicating path  171  has its front/rear and upper/lower surfaces demarcated by the upper wall  104 , the inner wall  73 , the inner wall  74 , the inner wall  75 , the inner wall  76 , and the inner wall  77 . Moreover, the first communicating path  171  has its left surface demarcated by the inner wall  71 , and has its right surface demarcated by the film  142 . 
     A lower end of the second communicating path  172  communicates with an upper end of the upper ink chamber  52  of the second ink chamber  132 . The second communicating path  172  extends upwardly from a communicating position with the upper ink chamber  52 , then extends frontwards, then extends upwardly, and then extends frontwards to reach the through hole  175 . 
     The second communicating path  172  has its rear surface and its upper surface demarcated by the rear wall  110 , the upper wall  104 , the rear wall  144 B of the protrusion  144 , and the upper wall  144 C of the protrusion  144 . In addition, the second communicating path  172  has its front surface and its lower surface demarcated by the inner wall  73  and the inner wall  76 . Moreover, the second communicating path  172  has its left surface demarcated by the inner wall  71 , and has its right surface demarcated by the film  142 . 
     As depicted in  FIGS. 5 and 7 , the third communicating path  173  includes a leftward communicating path  176  (an example of a first atmosphere communication passage), a rightward communicating path  177  (an example of a second atmosphere communication passage), a rearward communicating path  178 , and a labyrinth  179 . 
     The leftward communicating path  176  extends leftwards from the through hole  175  (refer to  FIGS. 6 and 7 ) to a left end of the frame  141 . In other words, the leftward communicating path  176  extends from the right surface toward the left surface of the ink chamber  111 . The leftward communicating path  176  communicates with the first communicating path  171  and the second communicating path  172  via the through hole  175 . Now, the first communicating path  171  communicates with the first ink chamber  131 , and the second communicating path  172  communicates with the second ink chamber  132 . Hence, an end section on a through hole  175  side of the leftward communicating path  176  (an end section on a right surface side of the ink chamber  111  in the leftward communicating path  176 ) communicates with the ink chamber  111 . The leftward communicating path  176  communicates with the rightward communicating path  177  via an opening  180 . The opening  180  is formed by a left lower end section of the inner wall  78  being cut out rightwards from a left end. The opening  180  is demarcated by the inner wall  78 , the inner wall  152 , and the film  143 . 
     The leftward communicating path  176  has its front surface demarcated by the inner wall  78 , has its rear surface and its lower surface demarcated by the inner wall  152 , has its upper surface demarcated by the upper wall  144 C of the protrusion  144 , and has its left surface demarcated by the film  143 . 
     The rightward communicating path  177  extends rightwards from the opening  180  to a right end of the frame  141 . In other words, the rightward communicating path  177  extends from the left surface toward the right surface of the ink chamber  111 . As mentioned above, the rightward communicating path  177  communicates with the leftward communicating path  176  at the opening  180 . In other words, an end section on an opening  180  side of the rightward communicating path  177  (an end section on a left surface side of the ink chamber  111  in the rightward communicating path  177 ) communicates with an end section on an opening  180  side of the leftward communicating path  176  (an end section on a left surface side of the ink chamber  111  in the leftward communicating path  176 ). As depicted in  FIGS. 4, 6, and 7 , an opening  181  is formed in a portion where the rightward communicating path  177  is formed in the inner wall  71 . A left side and a right side of the inner wall  71  in the rightward communicating path  177  are communicated by the opening  181 . 
     As depicted in  FIG. 4 , a surrounding wall  182  protrudes rightwards from a peripheral edge of the opening  181  in the inner wall  71 . A lower inner surface  182 A of the surrounding wall  182  inclines such that its right end is positioned more upwardly than its left end. A semipermeable membrane  183  (refer to  FIG. 4 ) is attached to a protruding tip surface of the surrounding wall  182 , in other words to a right surface of the surrounding wall  182 . As a result, the rightward communicating path  177  is blocked by the semipermeable membrane  183 . 
     The semipermeable membrane  183  is a porous membrane having minute holes that block passage of ink and allow passage a gas. For example, the semipermeable membrane  183  is composed of a fluororesin such as polytetrafluoroethylene, polychlorotrifluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-perfluoroalkylvinyl ether copolymer, tetrafluoroethylene-ethylene copolymer, and so on. 
     As depicted in  FIGS. 5 and 7 , a portion on a side more leftward than the inner wall  71  of the rightward communicating path  177  has its front surface and its lower surface demarcated by the inner wall  152 , has its rear surface demarcated by the inner wall  78 , has its upper surface demarcated by the upper wall  144 C of the protrusion  144 , has a portion excluding the opening  181  of its right surface demarcated by the inner wall  71  (refer to  FIG. 6 ), and has its left surface demarcated by the film  143 . 
     Moreover, as depicted in  FIGS. 4 and 6 , a portion on a side more rightward than the inner wall  71  of the rightward communicating path  177  has its front surface demarcated by the front surface  144 A of the protrusion  144 , has its lower surface demarcated by the inner wall  77  and the lower inner surface  182 A of the surrounding wall  182 , has its rear surface demarcated by the inner wall  78 , has its upper surface demarcated by the upper wall  144 C of the protrusion  144 , has a portion excluding the opening  181  of its left surface demarcated by the inner wall  71 , and has its right surface demarcated by the film  142 . 
     As depicted in  FIGS. 5 and 7 , the rearward communicating path  178  communicates with a portion on the side more rightward than the inner wall  71  of the rightward communicating path  177 , via an opening  184  (refer to  FIGS. 6 and 7 ) formed between the front wall  144 A of the protrusion  144  and the inner wall  71 . The rearward communicating path  178  extends leftwards from the opening  184 , and then extends rearwards to reach the labyrinth  179  via an opening  185  formed between the inner wall  151  and the inner wall  152 . As will be mentioned later, the labyrinth  179  communicates with outside of the ink tank  100  via an air opening port  187 . In other words, the portion on the side more rightward than the inner wall  71  of the rightward communicating path  177  (in other words, the end section on the right surface side of the ink chamber  111  in the rightward communicating path  177 ) communicates with outside of the ink tank  100 . 
     The rearward communicating path  178  has its lower surface and its front surface demarcated by the inner wall  151  and the front wall  144 A of the protrusion  144 , has its rear surface and its upper surface demarcated by the inner wall  152 , has its right surface demarcated by the inner wall  71 , and has its left surface demarcated by the film  143 . 
     The labyrinth  179  is a communicating path that, by a plurality of separating walls  186  that extend in the up-down direction  7  being provided aligned in the front-rear direction  8 , extends along the front-rear direction  8  while repeating U-turns in the up-down direction  7 . One end (a front lower end) of the labyrinth  179  communicates with the rearward communicating path  178  via the opening  185 . The other end (a rear upper end) of the labyrinth  179  communicates with the air opening port  187  (refer to  FIG. 5 ). 
     The air opening port  187  is configured as a hole penetrating in the up-down direction  7  the upper wall  144 C of the protrusion  144 . A lower end of the air opening port  187  communicates with the labyrinth  179 . An upper end of the air opening port  187  communicates with outside of the ink tank  100 . The air opening port  187  is positioned more upwardly than the liquid surface of ink when the maximum permissible amount of ink has been stored in the ink chamber  111 , in the usable posture of the ink tank  100 . 
     From the above, as depicted in  FIG. 4 , the atmosphere communication passage communicates with the first ink chamber  131  of the ink chamber  111  at the opening  174 , and communicates with the second ink chamber  132  of the ink chamber  111  at a lower end of the second communicating path  172 . On the other hand, as depicted in  FIG. 5 , the atmosphere communication passage communicates with outside of the ink tank  100  at the air opening port  187 . 
     Ink Tank  100 B 
     A configuration of the ink tank  100 B will be described below with reference to  FIGS. 8 to 11 . As depicted in  FIGS. 8 and 9 , the ink tank  100 B is longer in the left-right direction  9  than the ink tanks  100 Y,  100 C,  100 M (refer to  FIGS. 4 and 5 ). 
     Portions different from the ink tanks  100 Y,  100 C,  100 M, of the ink tank  100 B will be described below. Note that portions having the same configuration as in the ink tanks  100 Y,  100 C,  100 M in the ink tank  100 B will be assigned with the same reference symbols as in  FIGS. 4 to 7 , whereupon descriptions thereof will be omitted. Moreover, in the case that a configuration of a certain portion in the ink tank  100 B differs only in being longer in the left-right direction  9  than a configuration of a portion corresponding to said certain portion of the ink tanks  100 Y,  100 C,  100 M, the portion corresponding to said certain portion in the ink tank  100 B will be assigned with the same reference symbol as in  FIGS. 4 to 7 , whereupon a description thereof will be omitted. 
     As depicted in  FIGS. 8 and 9 , the casing  140  of the ink tank  100 B includes the frame  141  and three films  139 ,  142 ,  143 . 
     As depicted in  FIGS. 8 and 10 , the ink tank  100 B includes a right wall  159 , but does not include the left wall  103  (refer to  FIG. 5 ) which is included in the ink tanks  100 Y,  100 C,  100 M. The right wall  159  is a wall extending rearwards from a right end of the front wall  101 . An upper end of the right wall  159  is connected to a front section of the upper wall  104 . A lower end of the right wall  159  is connected to a front section of the lower wall  105 . In other words, the right wall  159  is a wall joining the right end of the front wall  101 , a front section right end of the upper wall  104 , and a front section right end of the lower wall  105 . In other words, the right wall  159  is provided only in the front section of the frame  141 , and is not provided in the rear section of the frame  141 . 
     As depicted in  FIGS. 8 and 9 , a recess  162  is formed in the front section of the upper wall  104 . The recess  162  is demarcated by side walls  162 A,  162 B,  162 C and the upper wall  104 . 
     The ink tank  100 B does not include the inner wall  71  (refer to  FIG. 6 ). The ink tank  100 B includes an inner wall  160  (refer to  FIGS. 8 and 10 ) and an inner wall  161  (refer to  FIGS. 9 and 11 ) as walls corresponding to the inner wall  71  (refer to  FIG. 6 ). 
     The inner wall  160  and the inner wall  161  extend downwardly from the upper wall  104  and the upper wall  144 C of the protrusion  144 . The inner wall  160  and the inner wall  161  are walls extending in the up-down direction  7  and the front-rear direction  8 . 
     The inner wall  160  is provided in a range of hatching depicted in  FIG. 10 . The inner wall  160  is provided at a position between the right end and the left end of the frame  141 , in relation to the left-right direction  9 . For example, the inner wall  160  is provided more to a right side than a center of the frame  141 , in relation to the left-right direction  9 . 
     The inner wall  161  is provided in a range of hatching depicted in  FIG. 11 . The inner wall  161  is provided at a position more to a left side than the inner wall  160  between the right end and the left end of the frame  141 , in relation to the left-right direction  9 . For example, the inner wall  161  is provided more to a left side than the center of the frame  141 , in relation to the left-right direction  9 . 
     As depicted in  FIGS. 8 and 10 , a portion more upward than the inner wall  75  of the inner wall  73 , a portion on an inner wall  73  side of the inner wall  75 , the inner wall  76 , and the inner wall  77  extend rightwards from the inner wall  160 . In other words, the portion more upward than the inner wall  75  of the inner wall  73 , the portion on the inner wall  73  side of the inner wall  75 , the inner wall  76 , and the inner wall  77  are provided more to a right side than the inner wall  160 . 
     As depicted in  FIGS. 9 and 11 , the inner wall  74  and a portion on an inner wall  74  side of the inner wall  75  extend leftwards from the side wall  162 A. In other words, the inner wall  74  and the portion on the inner wall  74  side of the inner wall  75  are provided more to a left side than the side wall  162 A. 
     As depicted in  FIGS. 9 and 11 , the inner wall  74  extends downwardly from a left front section of the upper wall  104 . The inner wall  74  is connected to the side wall  162 A, but is not connected to the inner wall  160  and the inner wall  161 . 
     The inner wall  75  extends rearwards from a lower end of the inner wall  74 . A portion extending rearwards, of the inner wall  75  extends leftwards from the side wall  162 A. Then, the inner wall  75  extends rightwards. A portion extending rightwards, of the inner wall  75  has its front end connected to the side wall  162 B (refer to  FIG. 8 ) and its rear end connected to the front wall  144 A of the protrusion  144  (refer to  FIGS. 8 and 11 ). Then, the inner wall  75  extends rearwards. A portion extending rearwards, of the inner wall  75  extends rightwards from the inner wall  160 . 
     As depicted in  FIGS. 8 and 10 , a right end of the inner wall  79  is connected to the right wall  159 . 
     As depicted in  FIGS. 9 and 11 , the inner wall  151  is a wall joining the lower end of the front wall  144 A of the protrusion  144  and the rear wall  144 B of the protrusion  144 . The inner wall  151  extends rearwards from the lower end of the front wall  144 A, then extends upwardly, then extends rearwards, then extends upwardly, and then extends rearwards to reach the rear wall  144 B. 
     As depicted in  FIG. 8 , a rear section of the right surface of the frame  141  is open. The film  142  is welded to right surfaces of the lower wall  105 , the rear wall  110 , the upper wall  104 , the inner walls  72 ,  73 ,  75 - 79 , the side wall  162 B of the recess  162 , the front wall  144 A of the protrusion  144 , the rear wall  144 B of the protrusion  144 , and the upper wall  144 C of the protrusion  144 , whereby the right surface of the frame  141  is sealed. 
     As depicted in  FIG. 9 , the left surface of the frame  141  is open. The film  143  is welded to left surfaces of the rear wall  110 , the upper wall  104 , the lower wall  105 , the inner wall  72 , the inner wall  74 , the inner wall  75 , the inner wall  78 , the inner wall  79 , the inner wall  151 , the inner wall  152 , the front wall  144 A of the protrusion  144 , the rear wall  144 B of the protrusion  144 , the upper wall  144 C of the protrusion  144 , and the separating wall  186 , whereby the left surface of the frame  141  is sealed. 
     As depicted in  FIGS. 8 and 9 , the first ink chamber  131  is demarcated by the front wall  101 , the right wall  159 , the lower wall  105 , the rear wall  110 , the inner wall  72 , the inner wall  73 , the inner wall  74 , the inner wall  75 , the upper wall  104 , the inner wall  151 , the film  142 , and the film  143 . The right wall  159  and the film  142  demarcate the right surface of the first ink chamber  131 . 
     As depicted in  FIG. 9 , an upper end section of the inner wall  79  is cut out rightwards from a left end. As a result, an opening  163  is formed in the upper end section of the inner wall  79 . The opening  163  is demarcated by the inner wall  79 , the inner wall  75 , and the film  143 . A lower end section of the inner wall  79  is cut out rightwards from a left end. As a result, an opening  164  is formed in the lower end section of the inner wall  79 . The opening  164  is demarcated by the inner wall  79 , the inner wall  72 , and the film  143 . The front ink chamber  137  and the rear ink chamber  138  communicate by the openings  163 ,  164 . 
     A front end section of the inner wall  72  is cut out rightwards from a left end. As a result, an opening  165  is formed in the front end section of the inner wall  72 . The opening  165  is demarcated by the inner wall  72 , the lower wall  105 , and the film  143 . The front ink chamber  137  of the first ink chamber  131  and the lower ink chamber  51  of the second ink chamber  132  communicate by the opening  165 . 
     The right surface of the ink chamber  111  is demarcated by the right wall  159  and the left surface  142 L of the film  142 . In other words, part of the right surface of the ink chamber  111  is configured by the film  142 . 
     Moreover, the left surface of the ink chamber  111  is demarcated by the right surface  143 R of the film  143 . In other words, all of the left surface of the ink chamber  111  is configured by the film  143 . 
     The right surface and the left surface of the ink chamber  111  face each other in a state of being separated from each other. In other words, the right surface and the left surface of the ink chamber  111  are surfaces that face each other. 
     In the ink tank  100 B, present embodiment, a part of the film  142  configuring the right surface of the ink chamber  111  and a part of the film  143  configuring the left surface of the ink chamber  111 , of the right surface and the left surface of the ink chamber  111 , face each other. 
     Specifically, as depicted in  FIG. 12B , a portion more frontward than the inner wall  69  of the film  142  and a portion more rearward than the inner wall  79  and more frontward than the inner wall  69 , of the film  143 , face each other without another member interposing between them. In other words, the central section  142 A in the front-rear direction  8  of the film  142  and the central section  143 A in the front-rear direction  8  of the film  143  face each other. 
     Moreover, the rear section  142 B of the film  142  and the rear section  143 B of the film  143  face each other in a state that the inner wall  69  interposes between them. 
     Note that in the right surface of the ink chamber  111 , a portion facing the front section  143 C of the film  143  is the right wall  159 , not the film  142 . In other words, the front section  143 C of the film  143  does not face the film  142 . 
     As depicted in  FIGS. 8 and 10 , the first communicating path  171  and the second communicating path  172  are positioned more rightwards than the inner wall  160 . As depicted in  FIGS. 8 to 11 , the third communicating path  173  is positioned both rightwards of the inner wall  160  and leftwards of the inner wall  161 . 
     As depicted in  FIG. 9 , the first communicating path  171  communicates with the front ink chamber  137  of the first ink chamber  131  via an opening  166 . The opening  166  is formed by a left front end section of the inner wall  75  being cut out rightwards from a left end. The opening  166  is demarcated by the inner wall  75 , the inner wall  74 , and the film  143 . 
     The first communicating path  171  extends rearwards from the opening  166 , and then extends rightwards. Then, as depicted in  FIG. 8 , the first communicating path  171  extends rearwards, and then extends frontwards making a U-turn to reach the through hole  175  (refer to  FIG. 10 ). The through hole  175  is a hole penetrating the inner wall  160  and the inner wall  161  in the left-right direction  9 , and connects the first communicating path  171  and second communicating path  172  and the third communicating path  173 . 
     As depicted in  FIG. 9 , a portion extending rearwards from the opening  166  in the first communicating path  171  is demarcated by the upper wall  104 , the side wall  162 A of the recess  162 , the inner wall  74 , the inner wall  75 , and the film  143 . A portion extending rightwards in the first communicating path  171  is demarcated by the upper wall  104 , the side wall  162 B of the recess  162 , the inner wall  75 , and the front wall  144 A of the protrusion  144 . As depicted in  FIG. 8 , a portion more rightward than the inner wall  160  in the first communicating path  171  is demarcated by the inner wall  160 , the inner wall  73 , the inner wall  75 , the inner wall  76 , the inner wall  77 , and the film  142 . 
     As depicted in  FIG. 9 , the frame  141  includes a protrusion  167  protruding rearwards from the rear wall  110 . The protrusion  167  detects a height of the liquid surface of ink stored in the ink chamber  111  of the ink tank  100  in the usable posture, by being irradiated with light by a later-mentioned optical sensor  98 . The protrusion  167  has a rectangular parallelepiped shape. The protrusion  167  has an internal space  167 A, and a front end and a rear end of the protrusion  167  are open. A front end of the internal space  167 A of the protrusion  167  communicates with the upper ink chamber  52  of the second ink chamber  132 . In other words, the internal space  167 A is provided in the second ink chamber  132 . The rear end of the protrusion  167  is open. The open rear end of the protrusion  167  is blocked by a film  139  being attached to it. 
     When a horizontal cross section of the ink tank  100  at a height of not more than an upper end and not less than a lower end of the internal space  167 A of the protrusion  167  is viewed from above, a cross-sectional area of the second ink chamber  132  is smaller than a cross-sectional area of the first ink chamber  131 . Moreover, the internal space  167 A of the protrusion  167  communicates with the second ink chamber  132  of small cross-sectional area. 
     Note that in the present embodiment, the internal space  167 A of the protrusion  167  has communicated with the second ink chamber  132 , but the internal space  167 A may communicate with the first ink chamber  131 . In other words, the internal space  167 A may be provided in the first ink chamber  131 . In this case, the protrusion  167  may protrude from the front wall  101  or the left wall  103 , for example. 
     Moreover, in the present embodiment, the protrusion  167  is provided only in the ink tank  100 B, of the ink tanks  100 B,  100 Y,  100 C,  100 M. However, the protrusion  167  may be provided in at least one of the ink tanks  100 B,  100 Y,  100 C,  100 M. 
     Optical Sensor  98   
     The printer unit  11  includes the optical sensor  98 . The optical sensor  98  is installed in the casing  14 . As depicted by the broken lines in  FIG. 9 , the optical sensor  98  is positioned rightwards and leftwards of the protrusion  167  of the frame  141  of the ink tank  100 B, in a state where the tank set  99  has been installed on the inside of the casing  14 . 
     The optical sensor  98  includes a light-emitting section  98 A and a light-receiving section  98 B. The light-emitting section  98 A and the light-receiving section  98 B are disposed in the left-right direction  9  sandwiching the protrusion  167 . The light-emitting section  98 A is disposed rightwards of the protrusion  167 . The light-receiving section  98 B is disposed leftwards of the protrusion  167 . Note that arrangement positions of the light-emitting section  98 A and the light-receiving section  98 B may be left and right reversed. 
     Arrangement positions in the up-down direction  7  of the light-emitting section  98 A and the light-receiving section  98 B are determined such that a position of irradiation of light to the light-receiving section  98 B in the light-emitting section  98 A and a position of light reception of light from the light-emitting section  98 A in the light-receiving section  98 B are at a height of the second line  147  or less. In the present embodiment, as depicted in  FIG. 10 , the optical sensor  98  is positioned more downwardly than the second line  147 . In other words, a height of a position corresponding to an optical path of light irradiated from the optical sensor  98  in the protrusion  167  is at a lower position than the broken line depicted in  FIG. 10 . Now, said broken line indicates the liquid surface of ink of a minimum storage amount at which replenishment of ink becomes required in the ink tank in the usable posture. From the above, a position in the up-down direction  7  of the protrusion  167  includes a position more downward than the second line  147 . 
     The optical sensor  98  is electrically connected to a control unit (not illustrated) of the multifunction peripheral  10  via an electrical circuit. 
     Light is irradiated from the light-emitting section  98 A toward the light-receiving section  98 B. The irradiated light penetrates the protrusion  167  to enter the internal space  167 A of the protrusion  167 . When the liquid surface of ink stored in the internal space  167 A is more upward than the optical path, the light is blocked by the ink stored in the internal space  167 A to be prevented from reaching the light-receiving section  98 B. As a result, a low level signal is outputted from the optical sensor  98  to the control unit. On the other hand, when the liquid surface of ink is more downward than the optical path, the light proceeds through the air in the internal space  167 A. In this case, the light penetrates the internal space  167 A to reach the light-receiving section  98 B. As a result, a high level signal is outputted from the optical sensor  98  to the control unit. 
     The control unit determines that the liquid surface of ink stored in the ink chamber  111  is higher than the second line  147  when the signal outputted from the optical sensor  98  is low level, and determines that the liquid surface of ink stored in the ink chamber  111  is lower than the second line  147  when the signal outputted from the optical sensor  98  is high level. 
     Inlet  112   
     As depicted in  FIG. 1B , the inclined walls  106  of each of the ink tanks  100 B,  100 Y,  100 C,  100 M are respectively provided with inlets  112 B,  112 Y,  112 C,  112 M (these are sometimes described collectively as “inlet  112 ”) for filling ink into the first ink chamber  131  of the ink chamber  111 . The inlet  112  penetrates the inclined wall  106  in a thickness direction to communicate a corresponding first ink chamber  131  with outside of the ink tank  100 . An inner surface of the inclined surface  106  faces the front ink chamber  137  of the first ink chamber  131 . An outer surface of the inclined surface  106  faces outside of the ink tank  100 . Therefore, the inlet  112  directly communicates the first ink chamber  131  and outside of the ink tank  100 . In other words, in the present embodiment, the inlet  112  is provided in the first ink chamber  131  which is not provided with the protrusion  167 . Note that the inlet  112  may be provided for filling ink into the second ink chamber  132 . 
     The inclined wall  106  and the inlet  112  provided in the inclined wall  106  are exposed to outside of the multifunction peripheral  10  via the opening  22 , by the cover  70  being positioned in the open position. A posture (filling posture) of the ink tank  100  when ink is filled into the first ink chamber  131  via the inlet  112 , is the usable posture. That is, ink is filled into the first ink chamber  131  via the inlet  112  when the ink tank  100  is in the usable posture. 
     Cap  113   
     As depicted in  FIG. 1 , the ink tank  100  has caps  113 B,  113 Y,  113 C,  113 M that are attachable to/detachable from the inclined wall  106  so as to block the inlet  112 . The four caps  113 B,  113 Y,  113 C,  113 M correspond respectively to the four inlets  112 B,  112 Y,  112 C,  112 M of the ink tank  100 . As depicted in  FIG. 1A , the cap  113  installed in the inclined wall  106  closely contacts a wall surface demarcating a peripheral edge of the inlet  112  and thereby blocks the inlet  112 . On the other hand, as depicted in  FIG. 1B , the cap  113  removed from the inclined wall  106  opens the inlet  112 . The cap  113  is attached/detached to/from the inclined wall  106  in a state of the cover  70  being positioned in the open position. Moreover, removing the cap  113  from the inlet  112  makes it possible to fill ink into the ink chamber  111  via the inlet  112 . 
     Cover  70   
     As depicted in  FIG. 1 , the cover  70  is provided so as to enable opening/closing of the opening  22  formed in the front wall  14 A of the casing  14 . The cover  70  pivots around the pivotal axis  70 A extending in the left-right direction  9 . The cover  70  has an outer shape of a size corresponding to the opening  22 , and has a box-like shape opening toward the opening  22 . The cover  70  in the closed position covers the upright wall  102  and the inclined wall  106  of the front wall  101  of the ink tank  100 . The cover  70  in the open position exposes the upright wall  102  and the inclined wall  106  of the front wall  101  of the ink tank  100 , to outside of the casing  14 . 
     Function and Effect of Embodiment 
     Due to the above-described embodiment, both the right surface and the left surface of the casing  14  are configured by the thin films  142 ,  143 . Hence, the ink tank  100  can be miniaturized in the left-right direction  9 . Moreover, the amount of ink stored in the ink chamber  111  can be increased without changing external dimensions of the ink tank  100 . 
     In addition, due to the above-described embodiment, the right surface and the left surface of the ink chamber  111  face each other, hence a length in the left-right direction  9  of the ink tank  100  can be shortened. 
     Moreover, due to the above-described embodiment, part of the film  142  and part of the film  143  face each other, hence a proportion of portions configured by the films  142 ,  143  in the right surface and the left surface of the ink chamber  111  can be increased. As a result, the amount of ink stored in the ink chamber  111  can be increased without changing external dimensions of the ink tank  100 . 
     In addition, due to the above-described embodiment, the right surface and the left surface of the ink chamber  111  are parallel, hence a spacing between facing films  142 ,  143  can be shortened. As a result, the ink tank  100  can be miniaturized. 
     Moreover, due to the above-described embodiment, the films  142 ,  143  are welded to the casing  14 , hence the possibility of ink in the ink chamber  111  leaking out from a gap between the films  142 ,  143  and the casing  14 , can be lowered. 
     In addition, due to the above-described embodiment, the right surface and the left surface of the ink chamber  111  each have the first side along the front-rear direction  8  and the second side along the up-down direction  7  which are longer than the third side along the left-right direction  9 . Therefore, areas of the right surface and the left surface of the ink chamber  111  can be increased. As a result, a proportion of portions configured by the films  142 ,  143  in the casing  14  can be increased. As a result, the amount of ink stored in the ink chamber  111  can be increased without changing external dimensions of the ink tank  100 . 
     Moreover, due to the above-described embodiment, when the maximum permissible amount of ink is stored in the ink chamber  111 , the length of the portion, of the edge of the liquid surface of ink stored in the ink chamber  111 , defined by the films  142 ,  143  is longer than the length of the portion, of the edge, not defined by the films  142 ,  143 . Hence, a proportion of portions configured by the films  142 ,  143  in the casing  14  can be increased. As a result, the amount of ink stored in the ink chamber  111  can be increased without changing external dimensions of the ink tank  100 . 
     In addition, due to the above-described embodiment, both the right surface and the left surface of the casing  14  are configured by the thin films  142 ,  143 , hence it is possible to achieve a configuration including the leftward communicating path  176  and the rightward communicating path  177 . In order for ink to flow from the ink chamber  111  to outside of the casing  14 , the ink must flow leftwards along the leftward communicating path  176  and further flow rightwards along the rightward communicating path  177 . As a result, the possibility of ink leaking to outside of the casing  14  via the leftward communicating path  176  and the rightward communicating path  177 , can be lowered. 
     Moreover, due to the above-described embodiment, ink in the ink chamber  111  reaches the semipermeable membrane  183  by flowing leftwards along the leftward communicating path  176  and further flowing rightwards along the rightward communicating path  177 . As a result, the possibility of ink attaching to the semipermeable membrane  183  can be lowered. 
     Modified Embodiments 
     In the above-described embodiment, part of the film  142  and part of the film  143  faced each other in each of the ink tanks  100 . However, as depicted in  FIGS. 14 and 15 , the films  142 ,  143  need not face each other. In  FIG. 15 , a right side surface of the casing  140  is configured by the film  142 , and part of the rear wall  110  is configured by the film  143 . 
     Moreover, in the above-described embodiment, one inlet  112  was provided in each of the ink tanks  100 . However, two or more inlets  112  may be provided in each of the ink tanks  100 . 
     Moreover, in the above-described embodiment, one air opening port  187  was provided in each of the ink tanks  100 . However, two or more air opening ports  187  may be provided in each of the ink tanks  100 . 
     Moreover, in the above-described embodiment, one opening  158  out of which ink in the ink chamber  111  flows was provided in each of the ink tanks  100 . However, two or more openings  158  may be provided in each of the ink tanks  100 . 
     Moreover, in the above-described embodiment, the second ink chamber  132  included the buffer chamber  148  and the ink outflow passage  114 . However, the first ink chamber  131  may include the buffer chamber  148  and the ink outflow passage  114 . In this case, the buffer chamber  148  interposes between the first ink chamber  131  and the ink outflow passage  114 . In addition, both of the first ink chamber  131  and the second ink chamber  132  may include the buffer chamber  148  and the ink outflow passage  114 . 
     Moreover, in the above-described embodiment, ink was described as an example of the liquid. However, the present embodiment is not limited to this. That is, instead of ink, the likes of a pretreatment liquid discharged onto a recording sheet prior to the ink during printing, or water sprayed in a vicinity of the nozzle  40  of the recording head  39  for preventing drying of the nozzle  40  of the recording head  39 , may be examples of the liquid.