Patent Publication Number: US-8534811-B2

Title: Ink supply device supplying ink to recording head

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims priority from Japanese Patent Application No. 2011-284298 filed Dec. 26, 2011. The entire content of the priority application is incorporated herein by reference. 
     TECHNICAL FIELD 
     The present invention relates to an ink supply device that supplies ink from an ink tank storing the ink to a recording head mounted on a carriage through a tube. 
     BACKGROUND 
     As an example of the above ink supply device, there is known an ink-jet image recording apparatus that ejects ink based on an input signal to record an image onto a recording medium such as a recording sheet. The ink-jet image recording apparatus ejects ink supplied to a recording head from a nozzle to thereby record an image on the recording medium. 
     The recording head is mounted on a carriage and is made to reciprocate in a certain direction with respect to the recording medium. The carriage receives a driving force from a drive source such as a motor to reciprocate in a certain direction while being guided by a guide shaft or a guide tail. During the reciprocating motion of the carriage, ink droplets are selectively ejected from the recording head onto the recording medium. As a result, an image is recorded by the ink droplets landed onto the recording medium. 
     The ink to be used in the image recording is supplied from an ink tank provided in an ink cartridge so as to store the ink to the recording head mounted on the carriage through a channel member provided in the carriage and is ejected from the recording head. The channel member is a member constituting an ink channel. The channel member is resin-molded. 
     There is a method using a tube as a method of supplying the ink from the ink tank to the recording head. The tube serves as a channel for flowing the ink from the ink tank to the recording head (more specifically, a channel member) and is flexible enough to follow the reciprocating motion of the carriage. The tube has a length enough to connect the carriage and ink tank even when the carriage is moved to a position farthest from the ink tank. Thus, when the carriage is moved close to the ink tank, the tube is bent. 
     If an ink-jet image recoding apparatus has a function of recording a color image onto a recording medium, the ink tank and tube are each provided in plural. More specifically, the ink tank and tube are each provided for each of inks of colors (cyan (C), magenta (M), yellow (Y), and black (Bk)). 
     The plurality of tubes is arranged side-by-side. In a case where the tubes are arranged in a lateral direction (e.g., horizontal direction), a load to be applied when the tubes are bent varies among the tubes. This may cause the carriage connected to the tube to rattle. Further, the tubes are rubbed with each other during movement of the carriage, which may cause noise. 
     On the other hand, in a case where the tubes are arranged in a vertical direction (e.g., direction of gravitational force), if the ink leaks from a connection between the tube and channel member, the ink that has leaked from the connection of an upper tube may be adhered to the connection of a lower tube. In this state, when the connection of the lower tube and a sub-tank is released for maintenance and the connection thereof is made once again, the ink of the upper tube may go into the lower tube. 
     The arrangement of the plurality of tubes in the vertical direction is unfavorable for the following reason. In an ink-jet image recording apparatus, the channel member is provided with a damper unit for absorbing dynamic pressure caused by the reciprocating motion of the carriage. The damper unit is designed to be able to increase/decrease a volume of the channel member so as to absorb the dynamic pressure. For example, the damper unit is a film constituting one surface of the channel member. In this configuration, in the case where the plurality of tubes are arranged in the horizontal direction, the above-mentioned film can be shared between the inks of respective colors since a plurality of nozzles formed in the recording head are also arranged in the horizontal direction. That is, the film needs to be provided for only one surface of the ink channels of respective colors formed in the channel member. However, in the case where the plurality of tubes are arranged in the vertical direction, arrangement direction of the channels of the inks of respective colors inside the channel member needs to be changed from the vertical direction to horizontal direction. This complicates a configuration of the ink channels of respective colors inside the channel member, with the result that the film needs to be provided for two or more surfaces, for example, for each color. 
     To solve the above-described problem, a plurality of tubes is arranged in the vertical direction at a bent portion thereof and changed in arrangement direction at the carriage from the vertical direction to horizontal direction to be connected to connection ports provided in the carriage. 
     SUMMARY 
     However, the plurality of tubes is changed in arrangement direction at the carriage from the vertical direction to horizontal direction. In other words, the plurality of tubes is twisted at the carriage. The twisting applies unnecessary load to the tubes. As a result, the carriage connected to the tubes may be displaced or tilted by the load. 
     The present invention has been made in view of the above situation, and an object thereof is to provide an ink supply device capable of reducing a load to be applied to the plurality of tubes connected to the carriage. 
     In order to attain the above and other objects, there is provided an ink supply device including a storage portion configured to store ink, a carriage configured to be moved in a first direction, a recording head, a flow channel member, a plurality of tubes, and a tube retaining member. The recording head is mounted on the carriage and including nozzles that allow ink droplets to be ejected. The flow channel member is mounted on the carriage and includes a plurality of connection ports arranged in a second direction. The first direction and the second direction lay in an imaginary plane which is parallel to a recording sheet. The flow channel member includes a flow channel that allows the ink to flow from the plurality of connection ports to the recording head. The plurality of tubes each corresponds to each of the plurality of connection ports and each has one end and the other end. The one end is connected to the storage portion. The other end is connected to the corresponding connection port. The ink is configured to be supplied from the storage portion to the flow channel member through the plurality of tubes. Each of the plurality of tubes has a first portion adjacent to the other end and a second portion adjacent to the first portion. The first portion is positioned between the other end and the second portion. The tube retaining member is provided on the carriage and includes a first retaining portion configured to retain the first portions to be arranged in the second direction, and a second retaining portion configured to retain the second portions to be arranged in a third direction intersecting with the imaginary plane. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings: 
         FIG. 1  is a perspective view showing an external configuration of a multifunction apparatus according to an embodiment of the present invention; 
         FIG. 2  is a vertical cross sectional view showing an internal configuration of the multifunction apparatus shown in  FIG. 1 ; 
         FIG. 3  is a plan view showing an internal configuration of a printer unit shown in  FIG. 2 ; 
         FIG. 4  is a plan view showing an internal configuration of the printer unit without a cover shown in  FIG. 3 ; 
         FIG. 5  is a perspective view showing a carriage body to which a tube retaining member is attached; 
         FIG. 6  is an exploded perspective view showing the carriage body, the tube retaining member, and a joint in the carriage; 
         FIG. 7  is a perspective view showing a schematic configuration of a flow channel member; 
         FIG. 8  is a schematic view of ink tubes located on the joint and the tube retaining member; 
         FIG. 9A  is a schematic plan view showing an internal configuration of the printer unit according to a conventional configuration of the multifunction apparatus; and 
         FIG. 9B  is a schematic plan view showing an internal configuration of the printer unit according to the embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Next, an embodiment of the present invention will be described with reference to the accompanying drawings. It should be noted that the embodiment described below is merely illustrative of this invention and that appropriate changes and modifications may be made without departing from the spirit of this invention. 
     Schematic Configuration of Multifunction Apparatus  10   
     As illustrated in  FIGS. 1 and 2 , a multifunction apparatus  10  integrally includes a printer unit  11  and a scanner unit  12  and has a printer function, a scanner function, a copy function, and a facsimile function. The printer unit  11  is an example of ink supply device. 
     The printer unit  11  is provided at a lower portion of the multifunction apparatus  10 , and the scanner unit  12  is provided at an upper portion thereof. The printer unit  11  is connected to an external information device such as a computer and records an image or a character onto a recording sheet (example of a recording medium) based on print data including image data or document data and transmitted from the external information device. The scanner unit  12  is so-called a flat-bed scanner. 
     The multifunction apparatus  10  is substantially formed in a rectangular parallelepiped shape having a wide width and a thin thickness. That is, dimensions of the multifunction apparatus  10  in a width direction  101  and a depth direction  103  are larger than a dimension thereof in a height direction  102 . The width direction  101  corresponds to a left-right direction, the depth direction  103  to front-rear direction, and the height direction  102  to a vertical direction. The printer unit  11  has an opening  13  formed at the front surface thereof. The opening  13  has therein a sheet tray  20  and a sheet discharge tray  21 . A recording sheet accommodated in the sheet tray  20  is fed inside the printer unit  11 , and the recording sheet having a desired image formed thereon is discharged to the sheet discharge tray  21 . 
     In the following description, the side of the multifunction apparatus  10  on which the opening  13  is formed (the left side in  FIG. 2 ) will be called the “front side,” and the opposite side (the right side in  FIG. 1 ) will be called the “rear side.” Further, the left and right sides of the multifunction apparatus  10  will be based on the perspective of a user facing the front side of the multifunction apparatus  10 . In other words, the lower right side in  FIG. 1  will be the “right side,” while the upper left side will be the “left side.” 
     An operation panel  14  is provided at a front upper portion of the multifunction apparatus  10 . In the operation panel  14 , a predetermined input is performed thereon so as to allow the printer unit  11  and the scanner unit  12  to perform a desired operation. The operation panel  14  is provided with a plurality of buttons for use in input operation or a display for displaying an operating state of the multifunction apparatus  10  or error. When the multifunction apparatus  10  is connected to the external information device, the multifunction apparatus  10  can be operated based on a command transmitted from the external information device via communication software such as a printer driver or a scanner driver. 
     Printer Unit  11   
     As illustrated in  FIG. 2 , the sheet tray  20  is provided at the bottommost portion of the multifunction apparatus  10 . The sheet discharge tray  21  is provided above the sheet tray  20 . The sheet tray  20  and sheet discharge tray  21  are connected to each other by a sheet conveying path  23  so as to allow the recording sheet to be conveyed from the sheet tray  20  to the sheet discharge tray  21 . The recording sheet accommodated in the sheet tray  20  is guided along the sheet conveying path  23  so as to make a U-turn upward from bottom to be conveyed to an image recording unit  24 . The recording sheet onto which an image has been recorded by the image recording unit  24  is discharged to the sheet discharge tray  21 . 
     The sheet tray  20  has a vessel shape with an upper side opened. In this sheet tray  20 , the recording sheets are accommodated in a stacked state. For example, recording sheets of various sizes up to A3 size (A3 size, A4 size, B5 size, letter size, etc.) can be accommodated in the sheet tray  20 . 
     The sheet discharge tray  21  has a tray shape, and the recording sheet is discharged onto an upper surface of the tray. The sheet discharge tray  21  is disposed closer to the front surface of the printer unit  11  than the sheet tray  20  in the depth direction  103 . Thus, in the rear side, the sheet discharge tray  21  does not exist above the sheet tray  20 . 
     A sheet supply roller  25  is provided at the rear side of the sheet tray  20 . The sheet supply roller  25  supplies the recording sheets stacked in the sheet tray  20  to the sheet conveying path  23 . Driving force is transmitted to the sheet supply roller  25  from a not-illustrated motor to rotate the sheet supply roller  25 . The sheet supply roller  25  is rotatably supported to a tip end of a sheet supply arm  26 . The sheet supply arm  26  is configured to be able to pivot with a sheet supply roller  25  side set as a tip end side of the pivot. By the pivot, the sheet supply roller  25  moves up and down in such a direction as to close to or separate from the sheet tray  20 . The sheet supply arm  26  is biased by a weight of the sheet supply roller  25  or a spring to pivot downward and moves upward in accordance with an amount of the recording sheets accommodated in the sheet tray  20 . As a result, the sheet supply roller  25  comes into contact with the recording sheet positioned uppermost in the sheet tray  20 . When the sheet supply roller  25  is rotated in such a state, the recording sheet positioned uppermost is sent to the sheet conveying path  23  by a frictional force between a roller surface of the sheet supply roller  25  and the recording sheet. 
     The sheet conveying path  23  extends upward from the sheet tray  20  at the rear side, curves toward the front side, extends from the rear side to the front side along the depth direction  103 , and leads to the sheet discharge tray  21  through the image recording unit  24 . A portion of the sheet conveying path  23  other than portions where the image recording unit  24  and the like are provided is defined by an outer guide surface and an inner guide surface that face each other at a predetermined interval. For example, the portion of the sheet conveying path  23  curved at the rear side is defined by an outer guide member  18  and an inner guide member  19  that are fixed to an apparatus frame. 
     The image recording unit  24  includes a carriage  38 , a recording head  39 , and a platen  42 . The recording head  39  is mounted on the carriage  38 . The recording head  39  and the platen  42  are disposed to face each other at a predetermined interval. The detailed structure of the image recording unit  24  will be described later. 
     On an upstream side relative to the image recording unit  24  in a conveying direction of the recording sheet, a pair of conveying roller  60  and pinch roller are provided. Incidentally, in  FIG. 2 , the pinch roller is hidden by another member and is not illustrated, but the pinch roller is disposed on a lower side of the conveying roller  60  in a pressure contact state. The driving force is transmitted to the conveying roller  60  from a not-illustrated motor to rotate the conveying roller  60 . The conveying roller  60  and the pinch roller sandwich the recording sheet being conveyed through the sheet conveying path  23  to convey the recording sheet onto the platen  42 . 
     A pair of sheet discharge roller  62  and spur are provided on a downstream side relative to the image recording unit  24  in the conveying direction. Incidentally, in  FIG. 2 , the spur is hidden by another member and is not illustrated, but the spur is disposed on an upper side of the sheet discharge roller  62  in a pressure contact state. The driving force is transmitted to the sheet discharge roller  62  from a not-illustrated motor to rotate the sheet discharge roller  62 . The sheet discharge roller  62  and the spur sandwich the recorded recording sheet to transport the recoding sheet to the sheet discharge tray  21 . 
     Image Recording Unit  24   
     As illustrated in  FIG. 2 , the carriage  38  has the recording head  39  of the ink-jet type mounted thereon. As illustrated in  FIGS. 3 and 4 , inks of respective colors of cyan (C), magenta (M), yellow (Y) and black (Bk) are supplied to the recording head  39  from the ink tanks of ink cartridges  32  disposed independently of the recording head  39  in the multifunction apparatus  10  through ink tubes  41 . In  FIGS. 3 and 4 , the ink cartridges  32  and a cartridge attachment portion  33  to which the ink cartridges  32  are to be attached are schematically denoted by long dashed short dashed lines, respectively. While the carriage  38  is reciprocating, an image is recorded on the recording sheet conveyed on the platen  42  by selectively ejecting the inks of respective colors onto the recording sheet from nozzles of the recording head  39  as fine ink droplets. The ink cartridges  32  correspond to a storage portion and the ink tubes  41  to tubes. 
     As illustrated in  FIGS. 3 and 4 , a pair of guide rails  43  and  44  is provided so as to extend in the left-right direction (i.e., the width direction  101 ) intersecting with the conveying direction of the recording sheet and provided on an upper side of the sheet conveying path  23 . The pair of guide rails  43  and  44  is separated from each other at a predetermined distance in the conveying direction (in a direction from an upper side to a lower side in  FIGS. 3 and 4  corresponding to a fifth direction) of the recording sheet. The guide rails  43  and  44  are provided in a casing of the printer unit  11 , and constitute a part of a frame supporting respective members constituting the printer unit  11 . The carriage  38  is placed to straddle the guide rails  43  and  44  and can slide in an extending direction (the left-right direction in  FIG. 3 , i.e., the width direction  101 ) of the guide rails  43  and  44 . The width direction  101  corresponds to a first direction. 
     An edge portion  45  of the guide rail  44  on an upstream side in the conveying direction is bent upward substantially perpendicularly. The carriage  38  is slidably supported on the guide rails  43  and  44  with a sandwiching member, such as a pair of rollers, sandwiching the edge portion  45 . Thus, the carriage  38  is positioned with respect to the conveying direction (the direction from the upper side to the lower side in  FIG. 3 , i.e., the depth direction  103 ) of the recording sheet, and is slidable in the direction intersecting (perpendicular to, in this embodiment) with the conveying direction of the recording sheet. That is, the carriage  38  is slidably supported on the guide rails  43  and  44  and reciprocates in the direction intersecting with the conveying direction of the recording sheet based on the edge portion  45  of the guide rail  44 . 
     A belt drive mechanism  46  is provided on an upper surface of the guide rail  44 . The belt drive mechanism  46  has a drive pulley and a driven pulley  48  that are provided in the vicinities of both ends of the sheet conveying path  23  in the width direction  101  respectively and an endless annular timing belt  49  that is stretched between the drive pulley and the driven pulley  48  and has teeth provided on an inner surface thereof. In  FIGS. 3 and 4 , the drive pulley is hidden by a lower side of the carriage  38  and is not illustrated, but the drive pulley is disposed on a right end of the sheet conveying path  23  in the width direction  101 . A driving force is input to a shaft of the drive pulley from a not-illustrated motor. By rotation of the drive pulley, the timing belt  49  circularly moves around the drive pulley and the driven pulley  48 . 
     Although not illustrated in  FIGS. 3 and 4 , the carriage  38  is coupled to the timing belt  49  on a bottom surface side of the carriage  38 . When the timing belt  49  circularly moves around the drive pulley and the driven pulley  48 , the carriage  38  is reciprocated on the guide rails  43  and  44  on the basis of the edge portion  45  as a reference. The recording head  39  mounted on the carriage  38  is also reciprocated in the width direction  101  of the sheet conveying path  23  together with the carriage  38 . The recording head  39  mounted on the carriage  38  and the ink cartridges  32  are arranged in the depth direction  103  when the carriage  38  is located at a position closest to the ink cartridges  32 . 
     On a lower side of the sheet conveying path  23 , as illustrated in  FIG. 2 , the platen  42  is provided to face the recording head  39 . Incidentally, in  FIGS. 3 and 4 , the platen  42  is omitted, so that a frame  40  that supports the platen  42  from a lower side is illustrated. The platen  42  is provided to overlap a center portion through which the recording sheet passes within a range where the carriage  38  is reciprocated. A width of the platen  42  is sufficiently wider than a maximum width of the recording sheet usable in the printer unit  11 . The recording sheet is supported on an upper surface of the platen  42  so that a distance to the recording head  39  is maintained constantly. The ink droplets ejected from the recording head  39  land on the recording sheet. 
     A surface of the recording sheet onto which an image is to be recorded extends in the width direction  101  and depth direction  103  in a state where the recording sheet is supported by the platen  42 . That is, the carriage  38  reciprocated in the width direction  101  moves along the recording surface of the recording sheet. 
     Ink Tube  41   
     As illustrated in  FIGS. 3 and 4 , the ink cartridges  32  in which the inks of respective colors are stored respectively are attached to the cartridge attachment portion  33  of the printer unit  11 . 
     The four ink tubes  41  corresponding to the respective color inks extend from the cartridge attachment portion  33  to the carriage  38 . The ink tubes  41  extending to the carriage  38  supply the respective color inks to the recording head  39  mounted on the carriage  38 . That is, the respective color inks to be supplied from the ink cartridges  32  to the recording head  39  are distributed in the respective ink tubes  41 . The whole of the ink tubes  41  is located at an ink cartridge side with respect to the one connection port  59  in the depth direction  103 . The one connection port  59  is located at a position closest to the recording head  39 . 
     As illustrated in  FIG. 3 , one ends of the respective ink tubes  41  are connected to the cartridge attachment portion  33 . The ink tubes  41  extending along the width direction  101  from the cartridge attachment portion  33  are bent toward the front side and fixed to a clip  36  at the front side. Then, the ink tubes  41  are bent toward the rear side from the portion at which the ink tubes  41  are fixed to the clip  36  to the carriage  38  when the carriage  38  is located at a position closest to the ink cartridges  32 . More specifically, the ink tubes  41  are bent so as to make a U-turn toward the rear side as viewed from above. The bent ink tubes  41  extend in the width direction  101  and connected to the carriage  38 . More specifically, the ink tubes  41  are connected, at the other ends thereof, to respective connection portions  59  to be described later. The ink tubes  41  each have flexibility. Thus, the ink tubes  41  are bent following the reciprocation motion of the carriage  38  between the portion at which the ink tubes  41  are fixed to the clip  36  and the carriage  38 , and postures of the ink tubes  41  are changed. As illustrated in  FIG. 8 , each ink tube  41  has a first portion  41 A adjacent the other end and a second portion  41 B adjacent to the first portion  41 A. The first portion  41 A is positioned between the other end and the second portion  41 B. 
     The four ink tubes  41  are bundled so as to be arranged along the height direction  102  between the cartridge attachment portion  33  and a portion short of the carriage  38 . Inside of the carriage  38 , the four ink tubes  41  are twisted at 90° from a state of being arranged along the height direction  102  to a state being arranged along a horizontal direction. The twisted four ink tubes  41  are connected to the connection portions  59 , respectively. The twisted state of the four ink tubes  41  is retained in a tube retaining member  70  to be described later. 
     In this embodiment, the four ink tubes  41  have the same shape. More specifically, the four ink tubes  41  each have a circular cross-section, and the four ink tubes  41  have the same inner and outer diameters. As a matter of course, an embodiment in which the shapes of the four ink tubes are not the same may be adopted. Lengths of the four ink tubes  41  may be the same or different but preferably the same. Although the number of ink tubes  41  are four in this embodiment, the number of ink tubes  41  to be laid may be changed (e.g., six) in accordance with the number of ink colors. 
     Carriage  38   
     The carriage  38  has a carriage body  30  (see  FIGS. 5 and 6 ) and a cover  31  (see  FIG. 3 ). The carriage body  30  supports the recording head  39  (see  FIG. 2 ), a flow channel member  50  (see  FIGS. 4 and 7 ), a head control board  52  (see  FIG. 4 ), and the tube retaining member  70  (see  FIGS. 5 ,  6  and  8 ). 
     The carriage body  30  has a substantially rectangular parallelepiped shape with an upper side opened. The cover  31  is assembled to cover the opening of the carriage body  30 . The recording head  39 , the flow channel member  50 , the head control board  52 , and the tube retaining member  70  are accommodated in an inner space of the carriage body  30 . In the following description, a direction referred to merely as “upper side” or “lower side” is defined on the assumption that gravity is applied downward. 
     The recording head  39  is disposed at a bottom portion of the carriage body  30 . A nozzle surface, which is a lower surface of the recording head  39 , is exposed to a lower side of the carriage body  30 . This allows the ink droplets to be ejected from the nozzles toward the platen  42 . 
     Flow Channel Member  50   
     In the carriage body  30 , the flow channel member  50  is disposed above the recording head  39 . The flow channel member  50  has mainly a flow channel portion  55  (see  FIG. 7 ) formed with flow channel, a tank portion  56  (see  FIG. 7 ) storing the inks therein, and a joint  51  (see  FIG. 6 ) to be connected to the ink tubes  41 . 
     The flow channel portion  55  has a thin flat plate shape. In the flow channel portion  55 , four inlet ports  57  into which the respective color inks are injected are aligned in line. The inlet ports  57  are each formed in the flow channel portion  55  to have an upper side thereof opened. Further, the respective inlet ports  57  are arranged along a first arrangement direction  104 . 
     As illustrated in  FIG. 6 , the first arrangement direction  104  is oblique with respect to the width direction  101  and depth direction  103 . That is, in this embodiment, the first arrangement direction  104  intersects with the width direction  101 . Further, the first arrangement direction  104  is parallel to a virtual plane  105  parallel to a plane extending in the width direction  101  and depth direction  103 , i.e., the recording surface of the recording sheet. In this embodiment, an angle of an extending direction  106  perpendicular to the first arrangement direction  104  with respect to the width direction  101  is 25°. 
     The first arrangement direction  104  is not limited to the direction illustrated in  FIG. 6  as long as the first arrangement direction  104  is parallel to the virtual plane  105 . For example, the angle of the extending direction  106  with respect to the width direction  101  may be an angle different from that illustrated in  FIG. 6 . Further, the first arrangement direction  104  need not intersect with the width direction  101 . That is, the first arrangement direction  104  may be parallel to the width direction  101 . In this case, the angle of the extending direction  106  with respect to the width direction  101  is 90°. It is preferred, however, that the angle of the extending direction  106  with respect to the width direction  101  is 0°&lt;θ≦45°. The first arrangement direction  104  corresponds to a second direction. 
     As denoted by dashed lines in  FIG. 7 , in the flow channel portion  55 , four channels  58  are formed corresponding to the respective inlet ports  57 . The channels  58  extend from the respective inlet ports  57  in the width direction  101  to be bent perpendicularly and extend toward the tank portion  56  in the depth direction  103 . 
     In the flow channel member  50 , one surface (upper surface, in  FIG. 7 ) of the flow channel portion  55  is opened, and a film is welded to the opening. Forming the upper surface of the flow channel portion  55  with a sheet-like film allows the entire volume of the channels  58  to be increased/decreased. As a result, the flow channel member  50  provided with the film functions as a damper for absorbing dynamic pressure caused by the reciprocating motion of the carriage  38 . 
     The tank portion  56  is partitioned into four chambers corresponding to the four channels  58 . The color inks can be independently stored in the chambers respectively. The inks can flow into the chambers from the channels  58  respectively. Further, although not illustrated, the respective chambers of the tank portion  56  are coupled to the recording head  39  so as to enable the respective color inks to flow, and the inks discharged from the respective chambers of the tank portion  56  flow into the recording head  39 . Thus, the flow channel member  50  forms the ink channels between the inlet ports  57  and the recording head  39 . 
     The flow channel member  50  is assembled in the carriage body  30  so that the flow channel portion  55  and the tank portion  56  are arranged in the depth direction  103 . The flow channel portion  55  is disposed on the guide rail  44  side that is the front side, and the tank portion  56  is disposed on the guide rail  43  side that is the rear side. 
     As illustrated in  FIG. 6 , the joint  51  is disposed above the flow channel portion  55 . Although not illustrated, the joint  51  has four openings capable of connecting to the respective inlet ports  57  of the flow channel portion  55 . The four openings formed in a lower surface of the joint  51  are aligned in line, and the joint  51  is a long member in a direction in which the openings are aligned. The joint  51  is assembled in the flow channel portion  55  in a state where a longitudinal direction thereof is along the first arrangement direction  104 . As illustrated in  FIG. 7 , two pins  65  and  66  projecting upward are provided on the flow channel portion  55 . The above pins  65  and  66  are inserted into the joint  51 , and thereby the joint  51  is positioned with respect to the flow channel portion  55 . 
     As illustrated in  FIG. 6 , the connection portions  59  to be connected respectively to the ink tubes  41  are provided on an upper surface side of the joint  51 . The connection portions  59  correspond to connection ports. As illustrated in  FIG. 8 , four connection portions  59  are provided corresponding to the four ink tubes  41 . Like the inlet ports  57 , the four connection portions  59  are arranged in the first arrangement direction  104 . Each of the connection portions  59  has a cylindrical tube shape capable of being inserted into an inner space of each of the ink tubes  41 . The connection portions  59  are each disposed so that an axis direction of each of the cylindrical tube shapes is parallel to the extending direction  106 . The extending direction  106  is a direction perpendicular to the first arrangement direction  104  and parallel to the virtual plane  105 . The extending direction  106  corresponds to a fourth direction. 
     The ink tubes  41  are connected to the connection portions  59  respectively, allowing the inks to flow into the recording head  39  from the ink tubes  41  through the flow channel portion  55 . 
     Head Control Board  52   
     The head control board  52  (see  FIG. 4 ) is disposed on an upper side of the tank portion  56  of the flow channel member  50  in the carriage body  30 . The head control board  52  is a board that controls operation of the recording head  39  and is electrically connected thereto. The head control board  52  has various electronic elements mounted on a printed circuit board thereof. Descriptions of a circuit configuration of the head control board  52  are omitted here. 
     The head control board  52  is electrically connected to a control board (not illustrated) of the multifunction apparatus  10  by a FFC (Flexible Flat Cable)  53  (see  FIG. 4 ). The control board controls operation of the multifunction apparatus  10 . The head control board  52  outputs an electric signal such as a drive signal in order to control the operation of the recording head  39  based on an electric signal output from the control board. 
     Tube Retaining Member  70   
     As illustrated in  FIGS. 5 ,  6 , and  8 , the tube retaining member  70  is provided on the carriage body  30  at a portion above the flow channel portion  55  of the flow channel member  50  and adjacent to the joint  51 . The tube retaining member  70  is disposed such that a first retaining portion  71  to be described later faces the connection portions  59  in the extending direction  106 . 
     The tube retaining member  70  is formed into substantially a triangular shape as viewed from above and has various projections  74  (see  FIG. 6 ) on the triangular shape. The tube retaining member  70  is detachably mounted on the carriage body  30  by the various projections  74 . As illustrated in  FIG. 6 , the tube retaining member  70  is integrally provided with the first retaining portion  71  and a second retaining portion  72 . As illustrated in  FIG. 8 , the first retaining portion  71  is formed at a portion near a side  110  of the triangle opposite to an apex  109  thereof. The second retaining portion  72  is formed at a portion near the apex  109  of the triangle. 
     As described above, the connection portions  59  are each disposed so that the axis direction of each of the cylindrical tube shapes is parallel to the extending direction  106 . Thus, the ink tubes  41  connected respectively to the connection portions  59  extend in the extending direction  106 . The first retaining portion  71  faces the connection portions  59  in the extending direction  106  and, therefore, the first retaining portion  71  receives and retains the first portions  41 A of the plurality of ink tubes  41  extending in the extending direction  106 . 
     As illustrated in  FIGS. 6 and 8 , the first retaining portion  71  individually retains the four ink tubes  41  connected respectively to the connection portions  59  such that the four ink tubes  41  are arranged in the first arrangement direction  104 . In this embodiment, the first retaining portion  71  has four cutout portions  75  arranged in the first arrangement direction  104 . The four cutout portions  75  each have an entrance portion in the height direction  102  having an interval slightly smaller than the outer diameter of the each of the ink tubes  41  and have a bottom portion in the height direction  102  having an interval slightly larger than the outer diameter of the each of the ink tubes  41 . Thus, the ink tubes  41  pushed into the respective cutout portions  75  from their entrance portions are retained at their back portions. Further, the cutout portions  75  extend in the extending direction  106 . Accordingly, the ink tubes  41  retained in the first retaining portion  71  extend in the extending direction  106 . The surface of the bottom portion that is in contact with each ink tube  41  in the height direction  102  is located, in the height direction  102 , between the upper two ink tubes  41  retained in the second retaining portion  72  and the lower two ink tubes  41  retained in the second retaining portion  72 . 
     As illustrated in  FIGS. 6 and 8 , the second retaining portion  72  integrally bundles the second portions  41 B of the plurality of ink tubes  41  extending from the first retaining portion  71  along the extending direction  106  such that the ink tubes  41  are arranged in a second arrangement direction  107 . As illustrated in  FIG. 6 , the second arrangement direction  107  is a direction perpendicular to the virtual plane  105 , i.e., a direction coinciding with the height direction  102 . The second arrangement direction  107  corresponds to a third direction. Although the second arrangement direction  107  is perpendicular to the virtual plane  105  in this embodiment, the second arrangement direction  107  need not be perpendicular to the virtual plane  105  as long as the second arrangement direction  107  intersects with the virtual plane  105 . In this case, the second arrangement direction  107  does not coincide with the height direction  102 . 
     As illustrated in  FIGS. 6 and 8 , in this embodiment, the second retaining portion  72  is constituted by two plate-like members. The two plate-like members face each other in the first arrangement direction  104 . Further, the two plate-like members extend in the extending direction  106  (corresponding to the fourth direction) and second arrangement direction  107 . A length of each of the two plate-like members in the second arrangement direction  107  is slightly larger than a length of the four ink tubes  41  in a bundled state in the second arrangement direction  107 . Projections  73  are formed respectively at both end portions of the two plate-like members in the second arrangement direction  107 . An interval between the two plate-like members is slightly smaller at the portion at which the projections  73  are formed and slightly larger at the portion at which the projections  73  are not formed than an outer diameter of each of the ink tubes  41 . 
     With the above configuration, while a restoring force generated by twisting the ink tubes  41  between the first and second retaining portions  71  and  72  is applied between the two plate-like members constituting the second retaining portion  72 , the ink tubes  41  pushed between the two plate-like members through the portion at which the projections  73  are retained in the arrangement state in the second arrangement direction  107 . Further, the two plate-like members also extend in the extending direction  106 , so that the ink tubes  41  retained in the second retaining portion  72  extend in the extending direction  106 . The uppermost ink tube  41  in the second retaining portion  72  corresponds to the rearmost ink tube  41  in the first retaining portion  71  (the rearmost ink tube  41  corresponds to an uppermost ink tube  41  in  FIG. 8 ). That is, the ink tubes  41  are disposed sequentially downward in the second retaining portion  72  starting from the rearmost ink tube  41  in the first retaining portion  71  toward the frontmost ink tube  41  therein. 
     As described above, the ink tubes  41  extending from the cartridge attachment portion  33  and bent at the portion at which the ink tubes  41  are fixed to the clip  36  extend in the width direction  101  and are then connected to the carriage  38 . That is, the ink tubes  41  extending along the width direction  101  are turned in the extending direction  106  by being retained by the second retaining portion  72  of the tube retaining member  70 . That is, the ink tubes  41  are inserted into the carriage  38  obliquely with respect to the width direction  101 . 
     Thus, the tube retaining member  70  receives the plurality of ink tubes  41  extending from the plurality of connection portions  59  in the extending direction  106  and allows the ink tubes  41  to extend along the width direction  101 . In other words, the plurality of ink tubes  14  extending from the plurality of connection portions  59  further extends in a direction away from the tube retaining member  70 . 
     As illustrated in  FIG. 8 , in this embodiment, a position of the second retaining portion  72  in the first arrangement direction  104  corresponds to a center portion  108  of the plurality of connection portions  59  in the first arrangement direction  104 . That is, the second retaining portion  72  of the tube retaining member  70  retains the ink tubes  41  such that the ink tubes  41  are arranged in the second arrangement direction  107  at a position corresponding to the center portion  108  of the plurality of connection portions  59  in the first arrangement direction  104 . 
     The first and second retaining portions  71  and  72  of the tube retaining member  70  preferably extend in parallel to each other as viewed from above, as illustrated in  FIG. 8 . Although the center portion of the plurality of connection portions  59 , the center portion of the plurality of cutout portions  75  in the first arrangement direction  104 , and the center portion of the second retaining portion  72  in the first arrangement direction  104  are linearly aligned in the extending direction  106 , the positional relationship between the connection portions  59 , the cutout portions  75  of the first retaining portion  71 , and the second retaining portion  72  are not limited to this. That is, the center portion of the second retaining portion  72  in the first arrangement direction  104  may be linearly aligned with one of the center portions of the cutout portions  75  in the extending direction  106 . In this case, the second retaining portion  72  is preferably disposed inside relative to positions facing the cutout portions  75  of the first retaining portion  71  positioned at both ends in the first arrangement direction  104 . Further, the extending directions of the cutout portions  75  and second retaining portion  72  need not always be parallel to each other. 
     Effect of the Embodiment 
     According to the embodiment described above, the ink tubes  41  are twisted, at the tube retaining member  70 , to change their arrangement direction from the second arrangement direction  107  to the first arrangement direction  104 . However, the twisted ink tubes  41  are retained in the first retaining portion  71  and second retaining portion  72 . This can reduce a load applied to the carriage  38  due to the twisting of the ink tubes  41 . In particular, stress generated due to the twisting of the ink tubes  41  can be received by the first retaining portion  71 , thereby reducing stress applied to each connection portion  59 . 
     Further, according to the embodiment described above, the plurality of ink tubes  41  are led out from the carriage  38  in the extending direction  106  which is a direction inclined with respect to the width direction  101 . Thus, as illustrated in  FIG. 9B , in a state where the carriage  38  is moved to a position far away from the cartridge attachment portion  33  in the width direction  101 , a portion of the plurality of ink tubes  41  that extend in the extending direction  106  is included in a curved portion of the ink tubes  41 , with the result that a radius of curvature R 2  of the ink tubes  41  becomes large. On the other hand, in a conventional configuration in which the plurality of ink tubes  41  are led out from the carriage  38  in the width direction  101 , a radius of curvature R 1  of the ink tubes  41  becomes smaller than the radius of curvature R 2  of the present configuration, as illustrated in  FIG. 9A . When the radius of curvature of the ink tubes  41  is increased as in the embodiment described above, a load generated due to the curve of the ink tubes  41  and applied to the carriage  38  can be reduced. 
     Further, according to the embodiment described above, the surface of the bottom portion that is in contact with each ink tube  41  in the height direction  102  is located, in the second arrangement direction  107 , between the upper two ink tubes  41  retained in the second retaining portion  72  and the lower two ink tubes  41  retained in the second retaining portion  72 . Hence, in a case where the plurality of ink tubes  41  arranged in the second arrangement direction  107  are twisted in the first arrangement direction  104 , loads generated at two of the ink tubes  41  that are positioned at both end portions in the second arrangement direction  107  can be made substantially equal. 
     Further, according to the embodiment described above, the plurality of ink tubes  41  are twisted to change their arrangement direction from the second arrangement direction  107  to the first arrangement direction  104  at a position corresponding to the center portion  108  of the plurality of connection portions  59  in the first arrangement direction  104 . As a result, loads generated at two of the ink tubes  41  that are positioned at both ends in the arrangement direction due to the twisting of the ink tubes  41  can be made equal. 
     Further, according to the embodiment described above, the second arrangement direction  107  and virtual plane  105  are perpendicular to each other. The loads generated at the ink tubes  41  can be reduced in comparison with the loads generated at the ink tubes  41  that an arrangement direction of the ink tubes  41  is inclined with the virtual plane  105 .