Patent Publication Number: US-2023144530-A1

Title: Image recording apparatus

Description:
REFERENCE TO RELATED APPLICATIONS 
     This application claims priority from Japanese Patent Application No. 2021-183928 filed on Nov. 11, 2021. The entire content of the priority application is incorporated herein by reference. 
     BACKGROUND ART 
     There is a known image recording apparatus which heats at least one of a sheet and a liquid discharged onto the sheet to thereby fix the liquid to the sheet. For example, a publicly known image recording apparatus is provided with a body, a first cover attached to an upper part of the body so that the first cover is rotatable with respect to the body, and a thermal head supported by the body. The thermal head has a heating element which heats an ink ribbon so as to thermally transfer an ink of the ink ribbon to a roll paper. 
     In the above-described publicly known image recording apparatus, for example, in a case that the first cover is opened so as to release or open the inside of the body for a purpose of dissolving a paper jam, the thermal head is exposed. In this situation, there is such a fear that a user inadvertently or carelessly touches the thermal head. 
     DESCRIPTION 
     An object of the present disclosure is to provide an image recording apparatus capable of suppressing the occurrence of such a situation that in a case that the user opens the first cover, the user inadvertently touches a heater such as the thermal head. 
     According to an aspect of the present disclosure, there is provided an image recording apparatus including: a casing, a first cover, a conveyor, a recording head, a heater and a second cover. The first cover moves to an open position at which the first cover exposes an internal space of the casing to outside, and to a close position at which the first cover covers the internal space. The conveyor conveys a sheet in a conveying direction. The recording head discharges a liquid toward the sheet. The heater is supported by the casing and heats the sheet and/or the liquid on the sheet. The second cover covers the heater. The second cover moves to a cover position at which the second cover covers the heater and to an expose position at which the second cover allows the heater to be exposed to outside. 
    
    
     
       There is a case, for example, that a user moves the first cover from the close position to the open position as to dissolve a paper jam. Since the heater is covered by the second cover, it is possible to suppress the occurrence of such a situation that the user inadvertently touches the heater. Since the temperature of the air between the second cover and the heater becomes to be high by covering the heater by the second cover, the liquid discharged to the sheet is easily dried. On the other hand, the user is capable of exposing the heater to the outside by moving the second cover from the cover position to the expose position. Accordingly, it is possible to dissolve a paper jam occurred at the position at which the heater is located. 
         FIG.  1    is a perspective view depicting the outer appearance of an image recording apparatus  10 . 
         FIG.  2    is a perspective view depicting the outer appearance of the image recording apparatus  10  in a state that an upper casing  31  is opened. 
         FIG.  3    is a perspective view depicting side frames  20  and  21  attached to a base  23 . 
         FIG.  4    is a cross-sectional view of a IV-IV cross section of  FIG.  1   . 
         FIG.  5    is a perspective view of a jam cover  81  as seen obliquely thereabove. 
         FIG.  6    is a perspective view of the jam cover  81  as seen obliquely therebelow. 
         FIG.  7    is a cross-sectional view of a VII-VII cross section of  FIG.  5   . 
         FIG.  8    is a cross-sectional view of a VIII-VIII cross section of  FIG.  5   . 
         FIG.  9    is a block diagram of a controller  122 . 
         FIG.  10    is a view depicting a processing flow in the controller  122 . 
     
    
    
     Note that an embodiment which is to be explained below is not intend to limit or restrict the present disclosure; it is needless to say that the embodiment can be appropriately changed without changing the gist of the present disclosure. In the following explanation, an orientation in which a discharge port  33  faces or is oriented in a printer part  11  is referred to as “frontward (front, front-side)”, an orientation opposite to the frontward (front, front-side) is referred to as “rearward (rear, rear-side)”. As depicted in  FIG.  1   , the up-down direction is defined based on a state that the image recording apparatus  10  is usably arranged. Further, the left-right direction is defined, with the image recording apparatus  10  being seen from the rear. 
     &lt;Configuration of Outer Appearance of Image Recording Apparatus  10 &gt; 
     The image recording apparatus  10  as depicted in  FIG.  1    records, in the ink-jet recording system, an image on a sheet S pulled or drawn from a roll body  37  (see  FIG.  4   ). 
     As depicted in  FIG.  1   , the image recording apparatus  10  is provided with a casing  30 . The casing  30  is provided with an upper casing  31  (an example of a “first cover”) and a lower casing  32  (an example of a “casing”). The upper casing  31  and the lower casing  32  have, as a whole, a shape which is substantially rectangular parallelepiped, and have a size which can be placed on a table, desk, etc. In the following, in a case that an explanation is made regarding the casing  30 , the explanation is made assuming that the upper casing  31  and the lower casing  32  have the rectangular parallelepiped shape as a whole. 
     The casing  30  has a right surface  30 R, a left surface  30 L, an upper surface  30 U, a lower surface  30 D, a front surface  30 F, and a rear surface  30 B. The right surface  30 R and the left surface  30 L are positioned apart in the left-right direction. The upper surface  30 U and the lower surface  30 D are positioned apart in the up-down direction. The front surface  30 F and the rear surface  30 B are positioned apart in the front-rear direction. 
     The upper casing  31  is connected to the lower casing  32  to be pivotable (rotatable) about a rotation shaft A (see  FIG.  4   ) which extends in the left-right direction in the rear surface  30 B. The upper casing  31  is pivotally moved from a close position depicted in  FIG.  1    so that the front surface  30 F is lifted upward to pivot (rotate) to an open position depicted in  FIG.  2   . The upper casing  31  located at the close position does not cause or allows an internal space  30 A ( FIG.  4   ) of the casing  30  to be exposed to the outside. On the other hand, the upper casing  31  located at the open position allows the internal space  30 A of the casing  30  to be exposed to the outside. Note that in  FIG.  2   , the internal structure of the casing  30  is omitted. 
     As depicted in  FIG.  1   , the front surface  30 F of the casing  30  is formed with the discharge port  33  which extends to be slender in the left-right direction. The center part in the left-right direction of the discharge port  33  is positioned on the right side with respect to the center in the left-right direction of the front surface  30 F. The discharge port  33  causes the internal space  30 A of the casing  30  to communicate with the outside. The sheet S for which image recording has been performed in the internal space  30 A of the casing  30  is discharged to the outside of the casing  30  through the discharge port  33 . 
     An operation panel  44  is provided on the front surface  30 F of the casing  30 . The operation panel  44  is positioned above the discharge port  33 . The operation panel  44  receives input, from a user, the input being for operating the image recording apparatus  10  or for confirming a variety of kinds of settings. 
     As depicted in  FIG.  3   , two lateral frames  20 ,  21  are provided on the internal space  30 A of the casing  30 . Each of the lateral frames  20 ,  21  has a shape of a flat plate made of a steel plate, and a cutout, a through hole, etc., of which shape(s) is/are in accordance with a member which is supported by each of the lateral frames  20 ,  21 , are formed in each of the lateral frames  20  and  21 , as appropriate. The two lateral frames  20 ,  21  are positioned to be apart from each other in the left-right direction. The lateral frames  20 ,  21  are connected to a base  23  forming the lower surface  30 D of the casing  30 . The connection between the lateral frames  20 ,  21  and the base  23  is made by a screwing, a welding, etc. 
     &lt;Internal Configuration of Image Recording Apparatus  10 &gt; 
     A roll-body holder  35 , a tensioner  45 , a conveyor  71 , a recording head  38 , a heater  39 , a jam cover  81  (an example of a “second cover”), a supporting mechanism  116 , a supporting member  46 , a contact image sensor  25  (CIS  25 ; an example of a “reader”), a cutter unit  26  are arranged at a location between the lateral frames  20 ,  21  in the internal space  30 A. 
     As depicted in  FIG.  4   , in the internal space  30 A, a partition wall  41  is provided between the lateral frames  20  and  21 . The partition wall  41  is located at a lower part on the rear-side in the internal space  30 A. The partition wall  41  partitions a rear lower part of the internal space  30 A, while cooperating with the lower casing  32 , to define a sheet accommodating space  30 C. The sheet accommodating space  30 C is a space surrounded by the partition wall  41  and the lower casing  32  and separated or isolated from the recording head  38 , etc. 
     The roll body  37  is accommodated in the sheet accommodating space  30 C. The roll body  37  has a core tube and a long sheet S. The sheet S is wound around the core tube in a roll shape in a circumferential direction of the axial core of the core tube. The sheet S may have a width ranging from a minimum width to a maximum width in which the image recording apparatus  10  is capable of recording an image. Namely, a plurality of types of the roll body  37  having different widths are accommodatable in the sheet accommodating space  30 C. Note that it is allowable that the roll body  37  does not have the core tube and that the sheet S is wound in a roll shape so that the sheet S is installable in the roll-body holder  35 . Also note that the sheet accommodating space  30 C may accommodate a fan-folded paper. 
     The roll-body holder  35  is positioned in the sheet accommodating space  30 C. The roll body  37  is installed in the roll-body holder  35 . In a case that the roll body  37  is installed in the roll-body holder  35 , the roll-body holder  35  supports the roll body  37  so that the roll body  37  is rotatable in the circumferential direction of the axial core of the core tube of the roll body  37  in a state that the axial core of the core tube is along the left-right direction. 
     The roll-body holder  35  is provided with a pair of side guides  115  separated or apart from each other in the left-right direction. A distance between the pair of side guides  115  in the left-right direction is changeable. A user moves the pair of side guides  115  so as to cause the pair of side guides  115  to make contact, respectively, with left and right ends of the roll body  37 , in accordance with the width (the size along the left-right direction) of the roll body  37  to be installed to the roll-body holder  35 . The roll body  37  of which left and right ends make contact, respectively, with the pair of side guides  115  is positioned so that the center in the width direction of the sheet S is coincident with the center in the left-right direction of a conveying route  43 . The roll-body holder  35  rotates in a case that a driving force from a non-illustrated motor is transmitted to the roll-body holder  35 . Accompanying with the rotation of the roll-body holder  35 , the roll body  37  supported by the roll-body holder  35  also rotates. 
     A rear part of the sheet accommodating space  30 C is opened upward. Specifically, a gap  42  is defined between the partition wall  41  and the rear surface  30 B, namely, at a position above a rear end of the roll body  37 . The sheet S is drawn upward from the rear end of the roll body  37 , and the drawn sheet S is guided to the tensioner  45  via the gap  42 . 
     At a rear part of the internal space  30 A, the tensioner  45  is positioned above the partition wall  41 . The tensioner  45  is a roller supported by the lateral frames  20 ,  21  so that the tensioner  45  is rotatable. The tensioner  45  is supported by the lateral frames  20 ,  21  so that the tensioner  45  is movable in the front-rear direction. A rearward urging force is applied to the tensioner  45  by an urging member such as a spring, etc. 
     The conveyor  71  draws the sheet S from the roll body  37 , and conveys the sheet S frontward (an example of a “conveying direction”). The conveyor  71  has a conveying roller pair  36 , a first discharging roller pair  40 , and a second discharging roller pair  72 . 
     The conveying roller pair  36  is positioned in front of the tensioner  45 . The conveying roller pair  36  has a conveying roller  36 A and a pinch roller  36 B. The conveying roller  36 A is rotatably supported by the lateral frames  20  and  21 . The conveying roller  36 A rotates by a driving force transmitted thereto from a non-illustrated motor, thereby conveying the sheet S frontward while nipping the sheet S between the conveying roller  36 A and the pinch roller  36 B. 
     The first discharging roller pair  40  is positioned in front of the conveying roller pair  36 . The first discharging roller pair  40  has a discharging roller  40 A which makes contact with a lower surface of the sheet S, and a spur  40 B (an example of a “second rotating body”) which makes contact with an upper surface of the sheet S. The discharging roller  40 A is rotatably supported by the lateral frames  20 ,  21 . The discharging roller  40 A rotates by a driving force transmitted thereto from a non-illustrated motor, thereby conveying the sheet S frontward while nipping the sheet S between the discharging roller  40 A and the spur  40 B. The spur  40 B is rotatably supported by a first spur holder  74 . 
     The first spur holder  74  is formed to have a box shape having an internal space spreading in the front-rear direction, the up-down direction and the left-right direction. The first spur holder  74  has a plurality of pieces of the spur  40 B which project downward from a lower end of the first spur holder  74 . A first fitting part  91 , to which a first shaft  84  extending in the left-right direction is detachably and attachably fitted, is formed in an outer surface on the rear-side (rear outer surface) of the first spur holder  74 . The first shaft  84  is fixed to an internal frame (not depicted in the drawings) fixed to an inner wall surface of the upper casing  31 . Note that the first shaft  84  may be fixed to the lateral frames  20 ,  21  which are fixed to the base  23  of the lower casing  32 . 
     The first spur holder  74  is formed of a material made of a resin. The material of the first spur holder  74  is not particularly limited, provided that the material is capable of securing a strength and a heat-resisting property which are of not less than a certain level. For example, the first spur holder  74  is formed of polypropylene, polycarbonate, a phenol resin, etc. 
     The second discharging roller pair  72  is positioned in front of the first discharging roller pair  40 . The second discharging roller pair  72  has a discharging roller  72 A which makes contact with the lower surface of the sheet S, and a spur  72 B which makes contact with the upper surface of the sheet S. The discharging roller  72 A is rotatably supported by the lateral frames  20 ,  21 . The discharging roller  72 A rotates by a driving force transmitted thereto from a non-illustrated motor, thereby conveying the sheet S frontward while nipping the sheet S between the discharging roller  72 A and the spur  72 B. The spur  72 B is rotatably supported by a second spur holder  75 . 
     The second spur holder  75  is formed to have a box shape having an internal space spreading in the front-rear direction, the up-down direction and the left-right direction. The second spur holder  75  has a plurality of pieces of the spur  72 B which project downward from a lower end of the second spur holder  75 . A second fitting part  92 , to which a second shaft  85  extending in the left-right direction is detachably and attachably fitted, is formed in an outer surface on the front-side (front outer surface) of the second spur holder  75 . The second shaft  85  is fixed to the internal frame (not depicted in the drawings) fixed to the inner wall surface of the upper casing  31 . Note that the second shaft  85  may be fixed to the lateral frames  20 ,  21  which are fixed to the base  23  of the lower casing  32 . The second spur holder  75  is connected to the first spur holder  74  in the front-rear direction by a connecting member (not depicted in the drawings) which extends in the front-rear direction. Note that it is allowable that the second spur holder  75  is not connected to the first spur holder  74 . 
     The second spur holder  75  is formed of a material made of a resin. The material of the second spur holder  75  is not particularly limited, provided that the material is capable of securing a strength and a heat-resisting property which are of not less than a certain level. For example, the second spur holder  75  is formed of polypropylene, polycarbonate, a phenol resin, etc. 
     The recording head  38  is positioned at a location which is in front of (on the front-side with respect to) the conveying roller pair  36  and behind (on the rear-side with respect to) the first discharging roller pair  40 . The recording head  38  has a plurality of nozzles  38 A. Each of the plurality of nozzles  38 A discharges or ejects an ink (an example of a “liquid”), as a liquid droplet, toward the sheet S supported by a conveying belt  117 . With this, an image is recorded on the upper surface of the sheet S. A non-illustrated tank which stores the ink is connected to the recording head  38  by a non-illustrated tube so that the ink can be supplied from the tank to the recording head  38 . 
     As the ink, a water-based ink which includes water, a pigment and thermoplastic resin fine particles is used. Note that the ink is not particularly limited, provided that the ink can be fixed to the sheet S by heating. In the present embodiment, the ink adhered to the sheet S is heated by the heating part  39  to thereby melt the thermoplastic resin fine particles; and then the ink is subjected to cooling thereafter to thereby cure or harden the molten resin, thereby fixing the pigment included in the ink to the sheet S. 
     The heater  39  is positioned, in the front-rear direction, between the recording head  38  and the first discharging roller pair  40 . The heater  39  is fixed to the lateral frames  20 ,  21 . The heater  39  has: a metallic plate  39   a  which has a shape of a flat plate and which spreads in the front-rear direction and the left-right direction; and a polyimide heater  39   b  which is fixed to a lower surface of the metallic plate  39   a.  The metallic plate  39   a  supports the lower surface of the sheet S which is being conveyed frontward by the conveying belt  117 . Accordingly, a size in the left-right direction of the metallic plate  39   a  is greater than the maximum width, of the sheet S, in which the image recording apparatus  10  is capable of recording an image. The polyimide heater  39   b  heats the lower surface of the metallic plate  39   a.  With this, while the sheet S is passing on the metallic plate  39   a,  the thermoplastic resin fine particles included in the ink is melt by the heat of the metallic plate  39   a,  and the molten resin is cured by a colling by the atmosphere after the sheet S has passed the metallic plate  39   a,  thereby fixing the pigment to the upper surface of the sheet S. Note that it is allowable to heat the metallic plate  39   a  by a heater, such as an infrared heater, rather than by the polyimide heater  39   b.    
     A temperature sensor  121  configured to detect the temperature of the metallic plate  39   a  of the heater  39  is arranged at a location between the lateral frames  20 ,  21  in the internal space  30 A. In the present embodiment, two pieces of the temperature sensor  121  are fixed to the lower surface of the polyimide heater  39   b.  Each of the two temperature sensors  121  outputs a detection signal in accordance with the temperature of the polyimide heater  39   b  to a controller  122  (to be described later on). Note that the temperature sensor  121  may be fixed to the metallic plate  39   a.  Further, the temperature sensor  121  is not particularly limited, provided that the temperature sensor  121  is capable of outputting the detection signal in accordance with the temperature. For example, the temperature sensor  121  is exemplified by an infrared temperature sensor. 
     The jam cover  81  is arranged at a location above the heater  39 . The jam cover  84  faces the heater  39  in the up-down direction. The jam cover  81  is formed of a material made of a resin. The material of the jam cover  81  is not particularly limited, provided that the material is capable of securing a strength and a heat-resisting property which are of not less than a certain level. For example, the jam cover  81  is formed of polypropylene, polycarbonate, a phenol resin, etc. 
     The jam cover  81  is formed to have a box shape having an internal space  81 E which has a rectangular parallelepiped shape spreading in the front-rear direction, the up-down direction and the left-right direction. As depicted in  FIGS.  5  to  7   , the jam cover  81  has a cover body  81 A which is opened upward, a lid wall  81 B configured to close an opening  81 AA of the cover body  81 A, a plurality of spurs  81 C (an example of a “first rotating body”), and a plurality of spur cleaners  81 D. The cover body  81 A has a front wall  131  defining a front end of the internal space  81 E, a rear wall  132  defining a rear end of the internal space  81 E, a left wall  133  defining a left end of the internal space  81 E, and a right wall  134  defining a right end of the internal space  81 E. 
     The front wall  131  has a shape of a flat plate which has a thickness in the front-rear direction. The front wall  131  spreads in the up-down direction and the left-right direction. A front surface and a rear surface of the front wall  131  each have a rectangular shape which is longer in the left-right direction than in the up-down direction. A length in the left-right direction of the front wall  131  is longer than a length in the left-right direction of the metallic plate  39   a  of the heater  39 . The front wall  131  overlaps, in the front-rear direction, with the rear outer surface of the first spur holder  74 . 
     A guide wall  136  extending frontward from a lower end of the front wall  131  is formed. The guide wall  136  has a shape of a flat plate which has a thickness in the up-down direction. The guide wall  136  spreads in the front-rear direction and the left-right direction. The guide wall  136  spreads from a left end and reaches up to a right end of the front wall  131 . An upper surface and a lower surface of the guide wall  136  each have a rectangular shape which is longer in the left-right direction than in the front-rear direction. As depicted in  FIG.  4   , a front end of the guide wall  136  is positioned at the front-side with respect to a front end of the metallic plate  39   a  of the heater  39 . The upper surface and the lower surface of the guide wall  136  are inclined slightly downward. The guide wall  136  overlaps, in the up-down direction, with the first fitting part  91  of the first spur holder  74 . 
     The rear wall  132  is positioned at the rear-side with respect to the front wall  131 . The rear wall  132  has a shape of a flat plate which has a thickness in the front-rear direction. The rear wall  132  spreads in the up-down direction and the left-right direction. The rear wall  132  faces the front wall  131  in the front-rear direction. A front surface and a rear surface of the rear wall  132  each have a rectangular shape which is longer in the left-right direction than in the up-down direction. A length in the left-right direction of the rear wall  132  is longer than the length in the left-right direction of the metallic plate  39   a  of the heater  39 . 
     The bottom wall  133  closes a location between the lower end of the front wall  131  and a lower end of the rear wall  132 . The bottom wall  133  has a shape of a flat plate which has a thickness in the up-down direction. The bottom wall  133  spreads in the front-rear direction and the left-right direction. An upper surface and a lower surface of the bottom wall  133  each have a rectangular shape which is longer in the left-right direction than in the front-rear direction. A length in the left-right direction of the bottom wall  133  is longer than the length in the left-right direction of the metallic plate  39   a  of the heater  39 . 
     The bottom wall  133  is formed with a plurality of first slits  133 A which penetrate the bottom wall  133  in the up-down direction. The plurality of first slits  133 A extend in the front-rear direction. The plurality of first slits  133 A are arranged in the front-rear direction and in the left-right direction with a spacing distance therebetween. In the present embodiment, the plurality of first slits  133 A are arranged such that three first slits  133 A are arranged in the front-rear direction with the spacing distance therebetween and that five first slits  133 A are arranged in the left-right direction with the spacing distance therebetween. Each of the plurality of spurs  81 C protrudes to a location below the bottom wall  133  via one of the plurality of first slits  133 A. The number (quantity) of the first slit  133 A corresponds to the number (quantity) of the spur  81 C. 
     The left wall  134  connects a left end of the front wall  131 , a left end of the rear wall  132  and a left end of the bottom wall  133 . The left wall  134  has a shape of a flat plate which has a thickness in the left-right direction. The left wall  134  spreads in the front-rear direction and the up-down direction. 
     The right wall  135  connects a right end of the front wall  131 , a right end the rear wall  132  and a right end of the bottom wall  133 . The right wall  135  has a shape of a flat plate which has a thickness in the left-right direction. The right wall  135  spreads in the front-rear direction and the up-down direction. The right wall  135  faces the left wall  134  in the left-right direction. A projecting part  137  extending rearward is formed on a right surface of the right wall  135 . The projecting part  137  projects up to a location on the rear-side with respect to a rear surface of the rear wall  132 . The projecting part  137  is formed in the right surface of the right wall  135 , at an upper part on the side of the rear end thereof. The projecting part  137  is formed to have a shape of a letter “L” which extends rightward from the right surface of the right wall  135  and is bent rearward. A lower end of the projecting part  137  is located closely to a lower lock piece  119   a  of a lock part  119  (to be described later on) in the supporting mechanism  116  which is at a first position (to be described later on) (see  FIG.  5   ). 
     As depicted in  FIG.  7   , a plurality of regulating pieces  138  extending upward from the upper surface of the bottom wall  133  are formed in the upper surface of the bottom wall  133 . The plurality of regulating pieces  138  are arranged so that two pieces of the plurality of regulating pieces  138  sandwich each of the plurality of first slits  133 A therebetween in the left-right direction. Two regulating pieces  138  among the plurality of regulating pieces  138  sandwiching each of the plurality of first slits  133 A therebetween are positioned with equal spacing distances from the first slit  133 A in the left-right direction. Each of the plurality of regulating pieces  138  has a shape of a flat plate spreading in the front-rear direction and the up-down direction. The spacing distance between the two first regulating pieces  138  sandwiching one of the plurality of first slits  133 A in the left-right direction of is slightly longer than a length in the axial direction (axial length) of a first rotating shaft  81 CC of the spur  81 C. 
     Two first supporting pieces  139  extending upward from the upper surface of the bottom wall  133  are formed between the two regulating pieces  138  sandwiching each of the plurality of first slits  133 A. The two first supporting pieces  139  are positioned with equal spacing distances from the first slit  133 A in the left-right direction. Each of the two first supporting pieces  139  has a shape of a flat plate spreading in the front-rear direction and the up-down direction. Each of the two first supporting pieces  139  is formed with a second slit  139 A which is opened in an upper end of the first supporting piece  139  and which extends downward. The second slit  139  reaches, from the upper end of each of the two first supporting pieces  139 , to the upper surface of the bottom wall  133 . The second slit  139  is positioned at an intermediate position in the front-rear direction of each of the two first supporting pieces  139 . 
     As depicted in  FIGS.  7  and  8   , two second supporting pieces  140  extending upward from the upper surface of the bottom wall  133  are formed between the two first supporting pieces  139  sandwiching each of the plurality of first slits  133 A. The two second supporting pieces  140  face each other, in the left-right direction, with equal spacing distances from the first slit  133 A in the left-right direction. Each of the two second supporting pieces  140  has a shape of a flat plate spreading in the front-rear direction and the up-down direction. Each of the two second supporting pieces  140  extends from the rear surface of the front wall  131  up to the front surface of the rear wall  132 . Each of the two second supporting pieces  140  extends upward to a location above one of the two first supporting pieces  139 . A spacing distance in the left-right direction between the two second supporting pieces  140  sandwiching each of the plurality of first slits  133 A is slightly longer than an axial length of a rotating part  141  of each of the plurality of spur cleaners  81 D. Each of the two second supporting pieces  140  is formed with three third slits  140 A which are opened in an upper end of the second supporting piece  140  and which extends downward. The three third slits  140 A are arranged in the front-rear direction with equal spacing distances therebetween. The three third slits  140 A extend from the upper end of each of the two second supporting pieces  140  and reaches up to the upper surface of the bottom wall  133 . The three third slits  140 A overlap, in the left-right direction, with the second slits  139 A, of the two first supporting piece  139 , which sandwich each of the plurality of first slits  133 A therebetween. 
     The lid wall  81 B has a top plate part  151  defining an upper end of the internal space  81 E; a front plate part  152  extending downward from a front end of the top plate part  151 ; a rear plate part  153  extending downward from a rear end of the top plate part  151 ; a left plate part  153  extending downward from a left end of the top plate part  151 ; and a right plate part  155  extending downward from a right end of the top plate part  151 . 
     The top plate part  151  has a shape of a flat plate which has a thickness in the up-down direction. The top plate part  151  spreads in the front-rear direction and the left-right direction. The top plate part  151  closes a location among an upper end of the front wall  131  and an upper end of the rear wall  132 , an upper end of the left wall  134  and an upper end of the right wall  135  of the cover body  81 A. Namely, the top plate part  151  closes the opening  81 AA of the cover body  81 A. The front end of the top plate part  151  is positioned in front of (on the front-side with respect to) the front wall  131  of the cover body  81 A. The rear end of the top plate part  151  is positioned behind (on the rear-side with respect to) the rear wall  132  of the cover body  81 A. The left end of the top plate part  151  is positioned on the left side with respect to the left wall  134  of the cover body  81 A. The right end of the top plate part  151  is positioned on the right side with respect to the right wall  135  of the cover body  81 A. An upper surface and a lower surface of the top plate part  151  have a rectangular shape which is longer in the left-right direction than in the front-rear direction. 
     The front plate part  152  has a shape of a flat plate which has a thickness in the front-rear direction. The front plate part  152  spreads in the up-down direction and the left-right direction. The front plate part  152  spreads from the left end and reaches up to the right end of the top plate part  151 . The front plate part  152  extends downward up to a position close to the guide wall  136 . A grasping part (gripping part)  152 A which is recessed upward from a lower end of the front plate part  152 A is formed in an intermediate part in the left-right direction of the front plate part  152 . The grasping part  152 A is configured such that a user hooks a finger to the grasping part  152 A so as to cause the jam cover  81  to rotate easily from a cover position to an expose position (to be described later on). 
     The rear plate part  153  has a shape of a flat plate which has a thickness in the front-rear direction. The rear plate part  153  spreads in the up-down direction and the left-right direction. The rear plate part  153  spreads from the left end and reaches up to the right end of the top plate part  151 . A length in the up-down direction of the rear plate part  153  is shorter than a length in the  1  up-down direction of the front plate part  152 . 
     The left plate part  154  closes a location among the left end of the front plate part  152 , the left end of the rear plate part  153 , and the left end of the top plate part  151 . The left plate part  154  has a shape of a flat plate which has a thickness in the left-right direction. The left plate part  154  spreads in the front-rear direction and the up-down direction. A length in the up-down direction of the left plate part  154  is shorter than the length in the up-down direction of the front plate part  152 . 
     The right plate part  155  closes a location among the right end of the front plate part  152 , the right end of the rear plate part  153 , and the right end of the top plate part  151 . The right plate part  155  has a shape of a flat plate which has a thickness in the left-right direction. The right plate part  155  spreads in the front-rear direction and the up-down direction. A length in the up-down direction of the right plate part  155  is shorter than the length in the up-down direction of the front plate part  152 . 
     As depicted in  FIG.  5   , the lid wall  81 B is fixed to the cover body  81 A by a plurality of screws  156  which are arranged on the upper surface of the top plate part  151 . As depicted in  FIG.  7   , the lower surface of the top plate part  151  is formed with a plurality of ribs  157  which extend downward from the lower surface of the top plate part  151 . The plurality of ribs  157  are arranged in the front-rear direction and in the left-right direction, with a spacing distance therebetween. The plurality of ribs  157  are formed to have a forward end part (tip end part) which has a bifurcated shape so as to avoid the plurality of regulating pieces  138 . 
     The spurs  81 C and the plurality of spur cleaners  81 D are incorporated into the jam cover  81 . The spurs  81 C are in a state of being projecting (protruding) to a location below the bottom wall  133  via one of the plurality of first slits  133 A, and the first rotating shaft  81 CC of each of the spurs  81  is rotatably supported by the two first supporting pieces  139  and the two second supporting pieces  140 . Each of the spurs  81 C is positioned in the left-right direction by both ends in the axial direction of the first rotating shaft  81 CC approaching closely to the two regulating pieces  138  sandwiching one of the plurality of first slits  133 A. 
     A second rotating shaft  142  of each of the plurality of spur cleaners  81 D is rotatably supported by the two supporting pieces  140 . Each of the plurality of spur cleaners  81 D is positioned in the left-right direction by end surfaces in the axial direction of the rotating part  141  of each of the plurality of spur cleaners  81 D approaching closely to the two supporting pieces  140 . By the lid wall  81 B being fixed to the cover body  81 A by the plurality of screws  156 , the spurs  81 C and the plurality of spur cleaners  81 D are prevented, by the lid wall  81 B, from detached or falling out from the inside of the cover body  81 A, and there is provided a state that a forward end part of each of the plurality of ribs  157  makes contact with the first rotating shaft  81 CC of one of the spurs  81 C from thereabove, thereby positioning the spurs  81 C in the up-down direction. 
     As depicted in  FIGS.  4  and  6   , the jam cover  81  is attached to the lateral frames  20 ,  21  so that the jam cover  81  is rotatable about a rotation shaft B extending in the left-right direction. The rotation shaft B is arranged in a lower part in an end part on the rear-side of the cover body  81 A. The jam cover  81  is rotatable between a cover position at which the jam cover  81  covers the heater  39  so that the heater  39  is not exposed to the outside and to an expose position at which the jam cover  81  allows the heater  39  to be exposed to the outside. In the present embodiment, the jam cover  81  at the cover position covers a location above the heater  39  (see a sold line in  FIG.  4   ). The jam cover  81  at the expose position allows the heater  39  to be exposed to the outside, via an opening at a location above the loser casing  32  (see a broken line in  FIG.  4   ). 
     The supporting mechanism  116  is positioned between the heater  39  and the conveying roller pair  36 . The supporting mechanism  116  is positioned at a location below the recording head  38 . The supporting mechanism  116  faces the recording head  38  in the up-down direction. The supporting mechanism  116  has the conveying belt  117 , a supporting part  118  configured to support the conveying belt  117 , a lock part  119  formed in the supporting part  118 . 
     A driving force from a non-illustrate motor is transmitted to the conveying belt  117  so as to drive and rotate the conveying belt  117  so that the conveying belt  117  conveys the sheet S frontward while supporting the lower surface of the sheet S. The supporting part  118  spreads in the front-rear direction and the left-right direction. The lock part  119  extends upward from a right end part (an end part on the right side) in a front end part of the supporting part  118 . As depicted in  FIG.  5   , the lock part  119  has a lower lock piece  119   a  (an example of a “lock mechanism”) which is located closely to the lower end of the projecting part  137  of the jam cover  81 , and a rear lock piece  119   b  which is located closely to the rear end of the projecting part  137 . Note that the rear lock piece  119   b  may be omitted. The lower lock piece  119   a  may make contact with the lower end of the projecting part  137 . 
     As depicted in  FIG.  4   , in a case that a motor  123  (see  FIG.  9   ) is driven, the supporting mechanism  116  is configured to rotate about a rotation shaft C extending in the left-right direction. The rotation shaft C is positioned at a rear end part (an end part on the rear-side) of the supporting mechanism  116 . The supporting mechanism  116  is configured to be rotatable between a first position (see a solid line in  FIG.  4   ) at which the supporting mechanism  116  faces the recording head  38  in the up-down direction, and a second position at which a front end part of the supporting mechanism  116  is rotated to be apart from the recording head  38  than at the first position (see broken line in  FIG.  4   ). With this, the lower lock piece  119   a  of the lock part  119  of the supporting mechanism  116  which is at the first position is configured to make contact with the lower end of the projecting part  137  of the jam cover  81  which is being moved from the cover position to the expose position. As a result, the movement of the jam cover  81  from the cover position to the expose position is inhibited or prevented. Further, the lower lock piece  119   a  of the lock part  119  of the supporting mechanism  116  which is at the second position is configured to not make contact with the lower end of the projecting part  137  of the jam cover  81  which is being moved from the cover position to the expose position. As a result, the movement of the jam cover  81  from the cover position to the expose position is made possible. 
     The supporting member  46  is positioned in front of the heater  39 . A front part of the supporting member  46  faces or is opposite to the spurs  72 B in the up-down direction. A rear part of the supporting member  46  faces or is opposite to the spurs  40 B in the up-down direction. The supporting member  46  supports the lower surface of the sheet S which is being conveyed frontward by the first discharging roller pair  40 . 
     The CIS  25  is positioned in front of the heater  39 . The CIS  25  is positioned above the supporting member  46 . The CIS  25  is positioned, in the front-rear direction, between the first discharging roller pair  40  and the second discharging roller pair  72 . In a case that a reflected light, of a light emitted or radiated from an light source such as an LED and reflected off (by) the sheet S, is collected by a refractive index distribution type lens and to a line sensor, the CIS  25  is configured to output an electric signal corresponding to the intensity of the reflected light received by the line sensor. The CIS  25  is capable of reading an image on the recording surface (upper surface) of the sheet S. In the CIS  25 , the left-right direction is a reading line. 
     The cutter unit  26  is positioned in front of the second discharging roller pair  72 . The cutter unit  26  has a configuration wherein a cutter  28  is mounted on a cutter carriage  27 . The cutter carriage  27  moves in the left-right direction, by a non-illustrated belt-driving mechanism, etc. Accompanying with the movement of the cutter carriage  27 , the cutter  28  moves also in the left-right direction. By the movement of the cutter  28 , the sheet S positioned between the second discharging roller pair  72  and the discharge port  33  is cut along the left-right direction. 
     As depicted in  FIG.  3   , a substrate  130  is fixed to the lateral frame  20  at a left side part thereof. An arithmetic element serving as the controller  122 , a chip for a communication interface, various connectors, etc., are mounted on the substrate  130 . The substrate  130  is connected, by a non-illustrated flat cable, etc., to the recording head  38 , the motor(s), the operation panel  44 , etc., so that an electrical signal can be transmitted and received. Further, an electric power is supplied from a non-illustrated power supply unit to the substrate  130 . 
     As depicted in  FIG.  9   , the controller  122  is configured to control the motor  123  which drives the supporting mechanism  116 , based on the detection signal outputted from the temperature sensor  121 . The controller  122  is configured to start the control of the motor driving the supporting mechanism  116  in a case that the controller  122  receives an open-close signal outputted from an open-close sensor  124  configured to detect that the upper casing  31  is opened. 
     Next, an operation of the image recording apparatus  10  will be explained. 
     In a case that the conveying roller  36 A of the conveying roller pair  36  rotates, the sheet S is drawn upward from the roll body  37  in the sheet accommodating space  30 C, via the gap  42 . The sheet S drawn from the roll body  37  is conveyed frontward while being nipped between the conveying roller  36  and the pinch roller  36 B. The sheet S conveyed frontward by the conveying roller pair  36  is supported by the supporting part  118  of the supporting mechanism  116 . In this situation, the ink is discharged downward from the plurality of nozzles  38  of the recording head  38  to thereby record an image on the upper surface of the sheet S. The sheet S having the image recorded on the upper surface thereof is conveyed frontward by the conveying belt  117 . 
     The sheet S which is (being) conveyed frontward by the conveying belt  117  is supported by the upper surface of the metallic plate  39   a  of the heater  39 . While the sheet S is passing on the metallic plate  39   a,  the sheet S and the ink are heated by the heat of the metallic plate  39   a.  With this, the thermoplastic resin fine particles included in the ink are melted, and then are subjected to cooling by the air thereafter to thereby cure or harden the molten thermoplastic resin fine particles, thereby fixing the pigment included in the ink to the sheet S. In this situation, the jam cover  81  covering the location above the heater  39  functions as a heat shielding wall. Accordingly, the heat of the metallic plate  39   a  is less likely to be transmitted to the CIS  25 . 
     The sheet S heated in the heater  39  is conveyed frontward while being nipped between the discharging roller  40 A and the spurs  40 B of the first discharging roller pair  40 A. The sheet S which is being conveyed frontward by the first discharging roller pair  40  is supported by the supporting member  46 . In a case that the sheet S is supported by the supporting member  46 , the CIS  25  radiates the light from the light source toward the upper surface (recording surface) of the sheet S, and outputs an electric signal in accordance with the intensity of a reflected light of the light reflected off the sheet S. With this, the image of the upper surface (recording surface) of the sheet S is read by the CIS  25 . 
     The sheet S of which image has been read by the CIS  25  is conveyed frontward by the second discharging roller pair  72 . The sheet S which is conveyed frontward by the second discharging roller pair  72  is cut along the left-right direction by the cutter unit  26  in a state that a front part of the sheet S is exposed from the discharge port  33  to the outside of the casing  30 . The sheet S cut by the cutter unit  26  is discharged from the discharge port  33 . 
     On the other hand, in a case that any jam (paper jam) occurs during the operation of the image recording apparatus  10 , the user at first rotates the upper casing  31  from the close position to the open position so as to expose the internal space  30 A of the casing  30  to the outside. Next, the user removes or takes out a sheet S jammed or clogged in the conveying route  43 . In this situation, since the location above the heater  39  is covered by the jam cover  81 , it is possible to suppress the occurrence of such a situation that the user inadvertently touches the fixing par  39 . 
     Next, an explanation will be given, for example, about an operation of the controller  122  in a case that the user rotates the jam cover  81  so as to dissolve the jam occurring during the operation of the image recording apparatus  10 . 
     In a case that the upper casing  31  is opened and that the controller  122  receives the open-close signal from the open-close sensor  124 , the controller  122  starts the control of the motor which drives the supporting mechanism  116 . 
     As depicted in  FIG.  10   , in step S 1 , the controller  122  determines as to whether or not the temperature corresponding to the detection signal received from the temperature sensor  121  exceeds a predetermined temperature K 1 . In a case that the controller  122  determines that the temperature corresponding to the detection signal received from the temperature sensor  121  exceeds the predetermined temperature K 1  (Step S 1 : YES), the controller  121  maintains the motor driving the supporting mechanism  166  to be in a non-driving state, and performs the determination of step S 1  again. With this, since a state that the lower lock piece  119   a  of the lock part  119  of the supporting mechanism  116  is located closely to the lower end of the projecting part  137  of the jam cover  81  is maintained, the projecting part  137  of the jam cover  81  makes contact with the lower lock piece  119   a  even in a case that the user attempts to rotate the jam cover  81  from the cover position to the expose position. Accordingly, the movement of the jam cover  82  from the cover position to the expose position is inhibited. On the other hand, in a case that the controller  122  determines that the temperature corresponding to the detection signal received from the temperature sensor  121  is not more than the predetermined temperature K 1  (Step S 1 : NO), the controller  122  proceeds the processing to step S 2 . 
     In step S 2 , the controller  122  performs control of driving the motor  123  which drives the supporting mechanism  116 . With this, the supporting mechanism  116  rotates from the first position at which the supporting mechanism  116  faces the recording head  38  in the up-down direction to the second position at which the front end part of the supporting mechanism  116  is apart with respect to the recording head  38 , and thus the projecting part  137  of the jam cover  81  does not make contact with the lower lock piece  119   a  of the lock part  119  of the supporting mechanism  116  in a case that the user rotates the jam cover  81  from the cover position to the expose position. Accordingly, the user is capable of rotating the jam cover  81  from the cover position to the expose position. 
     Technical Effect of Embodiment 
     Since the image recording apparatus  10  is provided with the jam cover  81  configured to cover the heater  39 , it is possible, for example, suppress the occurrence of such a situation that in a case that the user moves the upper casing  31  from the close position to the open position in order to dissolve a paper jam, the user inadvertently touches the heater  39 . Since the temperature of the air between the jam cover  81  and the heater  39  becomes to be high by covering the heater  39  by the jam cover  81 , the liquid discharged to the sheet S is easily dried. On the other hand, since the user is capable of exposing the heater  39  to the outside by moving the jam cover  81  from the cover position to the expose position, it is possible to dissolve a paper jam occurred in the position of the heater  39 . 
     In the image recording apparatus  10 , since the controller  122  releases the fixing, by the lock mechanism  116 , of the jam cover  81  to the cover position, based on the detection signal outputted by the temperature sensor  121 , it is possible to suppress the occurrence of such a situation that the user inadvertently touches the heater  39 . 
     In the image recording apparatus  10 , since the lower lock piece  119   a  of the lock part  119  of the supporting mechanism  116  which is at the first position makes contact with the projecting part  137  of the jam cover  81  moving to the expose position, the movement of the jam cover  81  to the expose position is inhibited by the lower lock piece  119   a  of the lock part  119  of the supporting mechanism  116  which is at the first position. Accordingly, the fixing of the jam cover  81  by the supporting mechanism  116  can be maintained in a more ensured manner. On the other hand, since the lower lock piece  119   a  of the lock part  119  of the supporting mechanism  116  which is at the second position does not make contact with the projecting part  137  of the jam cover  81  moving to the expose position, the movement of the jam cover  81  to the expose position is not inhibited by the lower lock piece  119   a  of the lock part  119  of the supporting mechanism  116  which is at the second position. Accordingly, the fixing of the jam cover  81  by the supporting mechanism  116  can be released in a more ensured manner. 
     In the image recording apparatus  10 , since the jam cover  81  is formed to have the box shape having the internal space  81 E, the air layer is formed in the inside of the jam cover  81 . Accordingly, the radiation heat of the heater  39  is less likely to be transmitted to the jam cover  81 , the jam cover  81  is made thereby to easily function as a heat shielding wall with respect to the radiation heat of the heater  39 . As a result, since the radiation heat of the heater  39  is less likely reach the CIS  25 , it is possible to suppress occurrence of any reading failure by the CIS  25 . 
     In the image recording apparatus  10 , since the jam cover  81  has the spurs  81 C configured to make contact with the upper surface (recording surface) of the sheet S in the internal space  81 E, it is possible to suppress such a situation that the liquid discharged to the sheet S adheres to the jam cover  81 . Since the space is defined between the jam cover  81  and the heater  39 , the radiation heat of the heater  39  is less likely to be transmitted to the jam cover  81 . This makes the jam cover  81  to easily function as the heat shielding wall with respect to the radiation heat of the heater  39 . 
     In the image recording apparatus  10 , since the jam cover  81  has, in the internal space  81 E, the plurality of spur cleaners  81 D each of which is configured to make contact with one of the spurs  81 C and to rotate by following the rotation of one of the spurs  81 C, it is possible to remove the ink adhered to the spurs  81 C by the plurality of spur cleaners  81 D. 
     In the image recording apparatus  10 , since the front end part of the jam cover  81  overlaps, in the front-rear direction, with the rear end part of the first spur holder  74 , the radiation heat of the heater  39  is less likely reach the first spur holder  74 . Accordingly, the first spur holder  74  is made thereby to easily function as a heat shielding wall with respect to the radiation heat of the heater  39 , the radiation heat of the heater  39  is less likely reach the CIS  25 . Thus, it is possible to suppress occurrence of any reading failure by the CIS  25 . Further, the size of the image recording apparatus  10  is made small in the up-down direction. 
     While the invention has been described in conjunction with various example structures outlined above and illustrated in the figures, various alternatives, modifications, variations, improvements, and/or substantial equivalents, whether known or that may be presently unforeseen, may become apparent to those having at least ordinary skill in the art. Accordingly, the example embodiments of the disclosure, as set forth above, are intended to be illustrative of the invention, and not limiting the invention. Various changes may be made without departing from the spirit and scope of the disclosure. Therefore, the disclosure is intended to embrace all known or later developed alternatives, modifications, variations, improvements, and/or substantial equivalents. Some specific examples of potential alternatives, modifications, or variations in the described invention are provided below. 
     &lt;Modification&gt; 
     In the image recording apparatus  10 , although the heater  39  which is configured to fix the ink to the sheet S heats the sheet S and the ink, it is sufficient that the heater  39  heats at least one of the ink and the sheet S. In such a case, it is allowable, for example, that the heater is configured to heat the sheet S in advance, and to cause the ink to fix to the sheet S by the residual heat of the pre-heating. 
     In the image recording apparatus  10 , although the upper casing  31  is attached to the lower casing  32  such that the upper casing  31  is rotatable between the open position at which the upper casing  31  exposes the internal space  30 A of the casing  30  to the outside, and to the close position at which the upper casing  31  does not expose the internal space  30 A to the outside, it is allowable that the upper casing  31  is attached to the lower casing  32  such that the upper casing  31  is movable between the open position and the close position. For example, it is allowable that the upper casing  31  is attached to the lower casing  32  such that the upper casing  31  is movable, in the front-rear direction, between the open position and the close position with respect to the lower casing  32 . Alternatively, the upper casing  31  may be configured to be detachably attachable with respect to the lower casing  32 . Still alternatively, it is allowable that a part of the right surface  30 R or the left surface  30 L of the casing  30  is configured to be movable between the open position and the close position, rather than the upper casing  31 . 
     In the image recording apparatus  10 , although the jam cover  81  is attached to the lateral frames  20 ,  21  so that the jam cover  81  is rotatable between the cover position at which the jam cover  81  covers the heater  39  and the expose position at which the jam cover  81  allows the heater  39  to be exposed to the outside, it is allowable that the jam cover  81  is attached to the lateral frames  20 ,  21  such that the jam cover  81  is movable between the cover position and the expose position. For example, it is allowable that the jam cover  81  is configured to be movable, in the front-rear direction, between the cover position and the expose position. Alternatively, the jam cover  81  may be configured to be detachably attachable with respect to the lateral frames  20 ,  21 . 
     The present disclosure may be realized also in the following aspects. The image recording apparatus may include: a lock mechanism which performs fixing of the second cover to the cover position; a temperature sensor which outputs a detection signal in accordance with a temperature of the heater; and a controller. The controller may allow the lock mechanism to release the fixing, based on the detection signal output by the temperature sensor. 
     Since the controller allows the lock mechanism to release the fixing based on the detection signal output by the temperature sensor, it is possible to suppress the occurrence of such a situation that the user inadvertently touches the heater. 
     The image recording apparatus may include a supporting mechanism which is configured to face the recording head and which supports the sheet. The supporting mechanism may be movable to a first position at which the supporting mechanism faces the recording head and to a second position at which the supporting mechanism is apart from the recording head than at the first position. It is allowable that the lock mechanism is the supporting mechanism, and that the lock mechanism makes contact with the second cover moving to the expose position in a case that the lock mechanism is moved to the first position, and does not make contact with the second cover moving to the expose position in a case that the lock mechanism is moved to the second position. 
     The movement of the second cover to the expose position is prevented by the supporting mechanism which is moved to or which is at the first position. Accordingly, the fixing of the second cover by the lock mechanism is maintained in a more ensured manner. Further, by the supporting mechanism which is moved to or which is at the second position, the movement of the second cover to the expose position is not prevented. Due to this, the fixing of the second cover by the lock mechanism is released in a more ensured manner. 
     The image recording apparatus may further include a reader which is positioned at downstream of the second part in the conveying direction and which reads an image on the sheet. The second cover may define an internal space. 
     Since the second cover has the internal space, an air layer is formed in the inside of the second cover. Accordingly, since the radiation heat of the heater is less likely to be transmitted to the second cover, the second cover is made thereby to easily function as a heat shielding wall (heat insulating wall) with respect to the radiation heat of the heater. As a result, since the radiation heat of the heater is less likely reach the second cover, it is possible to suppress occurrence of any reading failure (unsatisfactory reading) by the reader. 
     A first rotating body which makes contact with a recording surface of the sheet may be provided on the internal space defined by the second cover. 
     It is possible to suppress the occurrence of such a situation that the liquid discharged to the sheet adheres to the second cover. Since a space is defined between the second cover and the heater, the radiation heat of the heater is less likely to be transmitted to the second cover. This makes the second cover to easily function as the heat shielding wall with respect to the radiation heat of the heater. 
     A cleaner which makes contact with the first rotating body and which rotates by following rotation of the first rotating body may be provided on the internal space defined by the second cover. 
     It is possible to remove the liquid adhered to the first rotating body by the cleaner. 
     The image recording apparatus may further include a holder located between the reader and the heater in the conveying direction and supporting a second rotating body which makes contact with a recording surface of the sheet. A downstream end, of the second cover, at downstream in the conveying direction may overlap, in the conveying direction, with an upstream end, of the holder, at upstream in the conveying direction. 
     Since the downstream end on the downstream in the conveying direction of the second cover overlaps with the upstream end part on the upstream in the conveying direction of the holder, the radiation heat of the heater is less likely to reach the holder. This makes the holder to easily function as a heat shielding wall with respect to the radiation heat of the heater, and thus the radiation heat of the heater is less likely to reach the reader. Accordingly, it is possible to suppress occurrence of any reading failure by the reader. Further, the size of the image recording apparatus is made to be small in the up-down direction.