Patent Publication Number: US-2016236486-A1

Title: Inkjet printer

Description:
TECHNICAL FIELD 
     The disclosure relates to an inkjet printer which includes a platen configured to have a supporting surface for supporting a recording medium and a plurality of through-holes formed in the supporting surface, and a fan configured to produce a flow of gas, existing on the supporting surface side with respect to the through-holes, through the through-holes. 
     BACKGROUND ART 
     As an inkjet printer according to the related art, there is known an inkjet recording apparatus which includes an accommodating tray configured to accommodate recording sheets which are recording media, a side guide configured to regulate the rear ends of recording sheets in the accommodating tray, a recording head configured to eject ink, a platen configured to support each recording sheet onto which the recording head ejects ink, an intake fan that is a fan configured to produce a flow of gas, a slide shutter configured to be able to cover at least a part of the platen, a side pressing tool configured to be attached to the leading end portion of the slide shutter and suppress an end portion of each recording sheet from rising up from the platen, and a coupling arm configured to couple the side guide with the slide shutter, thereby transmitting linear motion of the side guide directly to the slide shutter (refer to Patent Document 1). 
     The platen of the inkjet recording apparatus disclosed in Patent Document 1 has a top surface which is a supporting surface for supporting each recording sheet, and a plurality of suction holes which are through-holes foimed in the top surface. 
     The intake fan of the inkjet recording apparatus disclosed in Patent Document 1 is configured to produce a flow of gas, existing on the top surface side of the platen with respect to the suction holes of the platen, through the suction holes. 
     The slide shutter of the inkjet recording apparatus disclosed in Patent Document 1 is configured to be able to cover at least a part of the top surface of the platen, thereby shielding at least some of the plurality of suction holes of the platen, and be able to change an area to cover the top surface of the platen. This slide shutter is configured to operate simultaneously with the side guide coupled with the slide shutter by the coupling aim, thereby being fixed at a position according to the width dimension of a recording sheet with respect to the platen. Also, in a case where the slide shutter is formed by a member which is deformable and flexible and has a flat plate shape, the slide shutter is configured to be able to be accommodated in a state where a range protruding from an end portion of the platen is bent, for example, downward. 
     PRIOR ART DOCUMENT 
     Patent Document 
     Patent Document 1: JP-A-2000-153604 
     SUMMARY 
     Problem to be Solved 
     The inkjet recording apparatus disclosed in Patent Document 1 does not include a heater configured to heat the platen. However, in the related art, there are known inkjet printers including heaters configured to heat platens. 
     In an inkjet printer including a platen configured to include a supporting surface for supporting each recording medium and a plurality of through-holes formed in the supporting surface, a fan configured to produce a flow of gas, existing on the supporting surface side with respect to the through-holes, through the through-holes, and a heater configured to heat the platen, since the platen heated by the heater is cooled by the flow of gas produced by the fan, the efficiency of heating of the platen by the heater is low. The inventor of this application focused attention on that point. 
     Therefore, the disclosure provides an inkjet printer capable of improving the efficiency of heating of a platen by a heater as compared to that in the related art. 
     Solutions to the Problem 
     An inkjet printer of the disclosure includes: a recording head that is configured to eject ink; a platen that is configured to support a recording medium onto which the recording head ejects ink; a heater that is configured to heat the platen; a fan that is configured to produce a flow of gas; and sheets that are configured to be able to cover at least a part of the platen, wherein the platen has a supporting surface for supporting the recording medium, and a plurality of through-holes formed in the supporting surface, wherein the fan produces the flow of gas, existing on the supporting surface side with respect to the through-holes, through the through-holes, and wherein the sheets can cover at least a part of the supporting surface, thereby capable of shielding at least some of the plurality of through-holes, and can change an area to cover the supporting surface. 
     According to this configuration, in the inkjet printer of the disclosure, since a part of the supporting surface of the platen which does not support a recording medium is covered by the sheets (hereinafter, referred to as a “medium non-support part”), whereby it is possible to shield the through-holes of the medium non-support part, it is possible to suppress gas from being forced to flow through the through-holes of the medium non-support part by the fan. Therefore, the inkjet printer of the disclosure can suppress cooling of the platen due to the flow of gas through the through-holes of the medium non-support part produced by the fan, and thus can improve the efficiency of heating of the platen by the heater as compared to that in the related art. 
     Also, in the inkjet printer of the disclosure, the heater may be disposed at a position on the opposite side of the through-holes to the supporting surface side, in a space where gas getting out of the through-holes passes. 
     According to this configuration, in the inkjet printer of the disclosure, since the heater is disposed in the space where gas entering through-holes from the supporting surface side of the platen and getting out of the through-holes passes, gas entering through-holes from the supporting surface side of the platen and getting out of the through-holes passes the vicinity of the heater, and thus the heater can be easily cooled by the gas. Therefore, the inkjet printer of the disclosure further improves the efficiency of heating of the platen by the heater as compared to a configuration in which the heater is not disposed in the space where gas getting out of through-holes passes. 
     Also, the inkjet printer of the disclosure may include winding members that are configured to be able to wind the sheets, and fixed members that are configured to be attached to the sheets attached to the winding members and be fixable at a plurality of positions with respect to the platen. 
     According to this configuration, in the inkjet printer of the disclosure, in a case where the sheets move with respect to the platen, the sheets are wound. Therefore, as compared to a configuration in which the sheets move with respect to the platen without being wound, it is possible to reduce a space for accommodating the sheets, and thus it is possible to reduce the size of the whole of the inkjet printer. 
     Also, the inkjet printer of the disclosure may include biasing members that are configured to bias the winding members in the winding directions of the sheets. 
     According to this configuration, in the inkjet printer of the disclosure, as long as the positions of the fixed members relative to the platen change, the sheets can be automatically wound around the winding members by the biasing forces of the biasing members. Therefore, as compared to a configuration in which a user manually winds the sheets around the winding members, it is possible to suppress the burden of a user. 
     Also, in the inkjet printer of the disclosure, the fixed members may be guide members that are configured to guide conveyance of the recording medium. 
     According to this configuration, in the inkjet printer of the disclosure, the fixed members have both of a function of fixing the sheets with respect to the platen and a function of guiding conveyance of a recording medium. Therefore, as long as the fixed members are fixed with respect to the platen according to the width of a recording medium in order to make the fixed members guide conveyance of the recording medium, it is possible to improve the platen heating efficiency of the heater by the sheets. 
     Technical Effects 
     The inkjet printer of the disclosure can improve the efficiency of heating of the platen by the heater as compared to that in the related art. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an inkjet printer according to an illustrative embodiment of the disclosure in a state where the inkjet printer is conveying a recording medium. 
         FIG. 2  is a sectional side view of the inkjet printer shown in  FIG. 1 . 
         FIG. 3  is a sectional front view of a part, surrounding a print platen, of the inkjet printer shown in  FIG. 1 . 
         FIG. 4  is a plan view of a part, surrounding the print platen, of the inkjet printer shown in  FIG. 1 . 
         FIG. 5  is a perspective view of a part, surrounding a guide member, of the inkjet printer shown in  FIG. 1  in a state where the inkjet printer is conveying a recording medium. 
         FIG. 6  is a block diagram of the inkjet printer shown in  FIG. 1 . 
         FIG. 7  is a sectional front view of a part, surrounding the print platen, of the inkjet printer shown in  FIG. 1  in a state where the inkjet printer is conveying a recording medium. 
         FIG. 8  is a plan view of a part, surrounding the print platen, of the inkjet printer shown in  FIG. 1  in a state where the inkjet printer is conveying a recording medium. 
     
    
    
     EMBODIMENTS OF THE DISCLOSURE 
     Hereinafter, an illustrative embodiment of the disclosure will be described with reference to drawings. 
     First, the configuration of an inkjet printer according to the illustrative embodiment will be described. 
       FIG. 1  is a perspective view of an inkjet printer  10  according to the illustrative embodiment in a state where the inkjet printer is conveying a recording medium  90  such as a sheet of paper. 
     As shown in  FIG. 1 , the inkjet printer  10  includes: a housing  11 ; a conveying device  12  configured to be disposed at a lower part of the housing  11  and convey a recording medium  90  in a sub scan direction shown by an arrow  10   b  and perpendicular to a main scan direction shown by an arrow  10   a;  a tank  13  configured to be disposed at an upper part of the housing  11  and contain ink; a guide rail  14  configured to extend in the main scan direction shown by the arrow  10   a;  a carriage  15  configured to be supported on the guide rail  14  so as to be movable in the main scan direction shown by the arrow  10   a;  a recording head  16  configured to be mounted on the carriage  15  and eject ink toward each recording medium  90 ; and a pressure damper  17  that is a device configured to be mounted on the carriage  15  and adjust the pressure of ink to be supplied from the tank  13  to the recording head  16  to a negative pressure of a predetermined range. 
     The housing  11  accommodates the guide rail  14 , the carriage  15 , the recording head  16 , and the pressure damper  17 . 
     The inkjet printer  10  is an apparatus configured to move the recording head  16  in the main scan direction, with respect to a recording medium  90  which does not move in the main scan direction shown by the arrow  10   a,  by the carriage  15 , and eject ink from the nozzles of the recording head  16  toward the recording medium  90 , thereby performing printing in the main scan direction with the recording head  16 . Also, the inkjet printer  10  is an apparatus configured to convey the recording medium  90  in the sub scan direction, with respect to the recording head  16  which is not move in the sub scan direction shown by the arrow  10   b,  by the conveying device  12 , thereby changing the position of the recording head  16  relative to the recording medium  90  in the sub scan direction whenever printing in the main scan direction finishes. 
       FIG. 2  is a sectional side view of the inkjet printer  10 . 
     As shown in  FIG. 2 , the inkjet printer  10  includes: a pre-platen  21  configured to be disposed on the upstream side of the recording head  16  in the conveyance direction of a recording medium  90  (refer to  FIG. 1 ) shown by an arrow  10   c  in the sub scan direction shown by the arrow  10   b  and to support the recording medium  90 ; a pre-heater  22  configured to heat the pre-platen  21  in order to preheat the recording medium  90  to be conveyed toward a position facing the recording head  16 ; a print platen  31  that is a platen of the disclosure configured to be disposed at a position facing the recording head  16  and support the recording medium  90 ; a print heater  32  that is a heater of the disclosure configured to be disposed at a position facing the recording head  16  and heat the print platen  31  in order to heat the recording medium  90 ; an after-platen  41  configured to be disposed on the downstream side from the recording head  16  in the conveyance direction shown by the arrow  10   c  and support the recording medium  90 ; and an after-heater  42  configured to heat the after-platen  41  in order to heat the recording medium  90  conveyed from the position facing the recording head  16 . 
     The print platen  31  is configured to have a supporting surface  31   a  for supporting each recording medium  90  and a plurality of through-holes  31   b  formed in the supporting surface  31   a.    
     The pre-heater  22  is a device configured to preheat a recording medium  90  to be conveyed toward the position facing the recording head  16 , through the pre-platen  21 , such that ink ejected by the recording head  16  dries up quickly from when the ink is attached to the recording medium  90 . 
     The print heater  32  is a device configured to be disposed at a position facing the recording head  16  and heat a recording medium  90  through the print platen  31 , such that ink ejected by the recording head  16  dries up quickly from when the ink is attached to the recording medium  90 . 
     The after-heater  42  is a device configured to heat a recording medium  90 , conveyed from the position facing the recording head  16 , through the after-platen  41 , such that ink ejected by the recording head  16  and attached to the recording medium  90  can surely dry up. 
     As described above, ink ejected by the recording head  16  and attached to a recording medium  90  dries up quickly and surely on the recording medium  90  by heat generated by the pre-heater  22 , the print heater  32 , and the after-heater  42 , whereby bleeding is suppressed. Therefore, the inkjet printer  10  can form high-quality images on recording media  90  with ink. 
     The inkjet printer  10  includes a wall member  51  which separates a space  20   a  where the pre-heater  22  is disposed, and a space  30   a  where the print heater  32  is disposed. Also, the inkjet printer  10  includes a wall member  52  which separates the space  30   a  and a space  40   a  where the after-heater  42  is disposed. Further, the inkjet printer  10  includes a base member  53  that blocks the bottom of the space  20   a,  a base member  54  that blocks the bottom of the space  30   a,  and a base member  55  that blocks the bottom of the space  40   a.    
     The inkjet printer  10  includes a fan  33  configured to be attached to the base member  54  and produce a flow of gas. The fan  33  is configured to suck gas in the space  30   a  and to discharge the gas out of the space  30   a,  thereby lowering the atmosphere pressure of the inside of the space  30   a.  If the atmosphere pressure of the inside of the space  30   a  falls, gas existing on a side of the supporting surface  31   a  with respect to the through-holes  3  lb of the print platen  31  moves into the space  30   a  through the through-holes  31   b.  In other words, the fan  33  is configured to produce a flow of gas, existing on the side of the supporting surface  31   a  with respect to the through-holes  31   b  of the print platen  31 , into the space  30   a  through the through-holes  31   b.    
     The print heater  32  is disposed inside the space  30   a.  In other words, the print heater  32  is disposed at a position on the opposite side of the side of the supporting surface  31   a  with respect to the through-holes  31   b  of the print platen  31 , and the print heater  32  is disposed inside the space  30   a  where gas getting out of the through-holes  31   b  passes. 
       FIG. 3  is a sectional front view of a part, surrounding the print platen  31 , of the inkjet printer  10 .  FIG. 4  is a plan view of a part, surrounding the print platen  31 , of the inkjet printer  10 . 
     As shown in  FIGS. 3 and 4 , the inkjet printer  10  (refer to  FIG. 1 ) includes: sheets  34  configured to be able to cover at least a part of the print platen  31 ; rollers  35  that are winding members configured to be able to wind the sheets  34 ; spiral springs  36  that are biasing members configured to bias the rollers  35  in the winding directions of the sheets  34 ; and guide members  37  configured to guide conveyance of each recording medium  90 . 
     The sheets  34  are attached to the rollers  35  and the guide members  37 . The sheets  34  can cover at least a part of the supporting surface  31   a  of the print platen  31 , thereby shielding at least a part of the plurality of through-holes  31   b.  The sheets  34  can change an area to cover the supporting surface  31   a , according to change in the positions of the guide members  37  related to the print platen  31 . Also, as a material for the sheet  34 , for example, a resin, a metal, or the like can be used. 
     The rollers  35  extend in the sub scan direction shown by the arrow  10   b,  and are supported on the housing  11  (refer to  FIG. 1 ) such that they are rotatable. 
     The spiral springs  36  are included inside the rollers  35 . One end of each spiral spring  36  is fixed to the housing  11 , and the other end thereof is fixed to a corresponding roller  35 . 
     The print platen  31  is provided with two guide grooves  31   c  formed so as to extend in the main scan direction shown by the arrow  10   a  and be separate from each other in the sub scan direction shown by the arrow  10   b.  The guide members  37  have protrusions (not shown) fit in the guide grooves  31   c  of the print platen  31 , and can be moved in the main scan direction shown by the arrow  10   a  as the protrusions are guided along the guide grooves  31   c.  The guide members  37  can be fixed at a plurality of positions with respect to the print platen  31  by frictional forces which are generated between the guide members and the print platen  31 . In other words, the guide members  37  constitute fixed members of the disclosure. 
       FIG. 5  is a perspective view of a part, surrounding a guide member  37 , of the inkjet printer  10  in a state where the inkjet printer is conveying a recording medium  90 . 
     As shown in  FIG. 5 , a guide member  37  includes a rising suppressing unit  37   a  configured to suppress rising up of an end of a recording medium  90  in the main scan direction shown by the arrow  10   a.    
       FIG. 6  is a block diagram of the inkjet printer  10 . 
     As shown in  FIG. 6 , the inkjet printer  10  includes: an operation unit  61  that is an input device such as buttons to which various operations of a user are input; a display unit  62  that is a display device such as an LCD (liquid crystal display) configured to display a variety of information; a communication unit  63  which is a communication device configured to perform communication with external apparatuses such as a PC (personal computer); the conveying device  12  and the recording head  16  described above; a carriage driving device  64  configured to move the carriage  15  (refer to  FIG. 1 ) in the main scan direction shown by the arrow  10   a  (refer to  FIG. 1 ); the pre-heater  22 , the print heater  32 , the after-heater  42 , and the fan  33  described above; and a control unit  65  configured to control the whole of the inkjet printer  10 . 
     The control unit  65  includes, for example, a CPU (central processing unit), a ROM (read only memory) configured to retain programs and a variety of data, a RAM (random access memory) configured to be usable as a work area of the CPU. The CPU is configured to execute programs retained in the ROM. 
     Now, operations of the inkjet printer  10  will be described. 
       FIG. 7  is a sectional front view of a part, surrounding the print platen  31 , of the inkjet printer  10  in a state where the inkjet printer is conveying a recording medium  90 .  FIG. 8  is a plan view of a part, surrounding the print platen  31 , of the inkjet printer  10  in a state where the inkjet printer is conveying a recording medium  90 . 
     As shown in  FIGS. 7 and 8 , a user can adjust the positions of the guide members  37  relative to the print platen  31 , according to the width of a recording medium  90  in the main scan direction shown by the arrow  10   a.    
     Further, the user can transmit print data from a computer such as a PC to the inkjet printer  10 . 
     If receiving the printing data through the communication unit  63 , the control unit  65  of the inkjet printer  10  drives the pre-heater  22 , the print heater  32 , the after-heater  42 , and the fan  33  while performing control on the basis of the print data received through the communication unit  63  such that the conveying device  12  conveys a recording medium  90  with respect to the recording head  16  in the sub scan direction shown by the arrow  10   b,  and the carriage driving device  64  moves the carriage  15  in the main scan direction shown by the arrow  10   a,  thereby moving the recording head  16  with respect to the recording medium  90  in the main scan direction, and the recording head  16  ejects ink toward the recording medium  90 , thereby printing an image based on the print data on the recording medium  90 . 
     In this stage, ink ejected by the recording head  16  and attached to the recording medium  90  dries up quickly and surely on the recording medium  90  by heat generated by the pre-heater  22 , the print heater  32 , and the after-heater  42 , as described above, whereby bleeding is suppressed. Therefore, the inkjet printer  10  can form high-quality images on recording media  90  with ink. 
     Also, a recording medium  90  which the conveying device  12  conveys in the conveyance direction shown by the arrow  10   c  is sucked onto the supporting surface  31   a  of the print platen  31  by suction force through the plurality of through-holes  31   b  of the print platen  31  caused by a flow of gas produced by the fan  33 , whereby rising up is suppressed. Therefore, the inkjet printer  10  can form high-quality images on recording media  90  with ink which is ejected toward the recording medium  90  by the recording head  16  disposed at the position facing the supporting surface  31   a  of the print platen  31 . 
     As described above, in the inkjet printer  10 , since a part of the supporting surface  31   a  of the print platen  31  which does not support a recording medium  90  (hereinafter, referred to as a “medium non-support part”) can be covered by the sheets  34 , whereby the through-holes  31   b  of the medium non-support part can be shielded, it is possible to suppress gas from being forced to flow through the through-holes  31   b  of the medium non-support part by the fan  33 . Therefore, the inkjet printer  10  can suppress cooling of the print platen  31  due to the flow of gas through the through-holes  31   b  of the medium non-support part produced by the fan  33 , and thus can improve the efficiency of heating of the print platen  31  by the print heater  32  as compared to that in the related art. 
     Also, in the inkjet printer  10 , in a case where the print platen  31  is cooled if the fan  33  causes gas to flow through the through-holes  31   b  of the medium non-support part, it is needed to rise the temperature of the print heater  32  in order to heat the print platen  31  to an appropriate temperature. However, in the inkjet printer  10 , since it is possible to suppress cooling of the print platen  31  due to the flow of gas through the through-holes  31   b  of the medium non-support part produced by the fan  33  as described above, it is unnecessary to rise the temperature of the print heater  32  unlike the above described case. In other words, the inkjet printer  10  can suppress unnecessary energy consumption. 
     Also, in the inkjet printer  10 , since it is possible to use the sheet  34  to suppress the flow of gas through the through-holes  31   b  of the medium non-support part from being produced by the fan  33 , as compared to a configuration in which gas is forced to flow through the through-holes  31   b  of the medium non-support part by the fan  33 , it is possible to improve suction force which a flow of gas produced by the fan  33  causes to be applied on a recording medium  90  through the plurality of through-holes  31   b  of the print platen  31 , and thus it is possible to improve the qualities of images formed on recording medium  90  with ink. 
     In the inkjet printer  10 , since the print heater  32  is disposed in the space  30   a  where gas entering the through-holes  31   b  from the side of the supporting surface  31   a  of the print platen  31  and getting out of the through-holes  31   b  passes, gas entering the through-holes  31   b  from the side of the supporting surface  31   a  of the print platen  31  and getting out of the through-holes  31   b  passes the vicinity of the print heater  32 , and thus the print heater  32  can be easily cooled by the gas. Therefore, the inkjet printer  10  further improves the efficiency of heating of the print platen  31  by the print heater  32 , as compared to a configuration in which the print heater  32  is not disposed in the space  30   a.    
     Also, the inkjet printer  10  may be configured such that the print heater  32  is not disposed in the space  30   a.    
     In the inkjet printer  10 , in a case where the sheets  34  move with respect to the print platen  31 , the sheets  34  are wound. Therefore, as compared to a configuration in which the sheets  34  move with respect to the print platen  31  without being wound, it is possible to reduce a space for accommodating the sheets  34 , and thus it is possible to reduce the size of the whole of the inkjet printer  10 . 
     Also, the inkjet printer  10  may be configured such that the sheets  34  move with respect to the print platen  31  without being wound. 
     In the inkjet printer  10 , as long as the positions of the guide members  37  relative to the print platen  31  change, the sheets  34  can be automatically wound around the rollers  35  by the biasing forces of the spiral springs  36 . Therefore, as compared to a configuration in which a user manually winds the sheets  34  around the rollers  35 , it is possible to suppress the burden of a user. 
     Also, the inkjet printer  10  may be configured such that a user manually winds the sheets  34  around the rollers  35 . 
     In the inkjet printer  10 , the guide members  37  have both of a function of fixing the sheets  34  with respect to the print platen  31  and a function of guiding conveyance of a recording medium  90 . Therefore, as long as the guide members  37  are fixed with respect to the print platen  31  according to the width of a recording medium  90  in order to make the guide members  37  guide conveyance of the recording medium  90 , it is possible to improve the efficiency of heating of the print platen  31  by the print heater  32  using the sheets  34 . 
     Also, the inkjet printer  10  may be configured such that the function of fixing the sheets  34  with respect to the print platen  31  and the function of guiding conveyance of a recording medium  90  are implemented by separate members, respectively. 
     Although the inkjet printer  10  is configured in the illustrative embodiment such that a recording medium  90  is moved with respect to the print platen  31 , it may be configured like a so-called flat bed type inkjet printer such that a recording medium  90  is not moved with respect to the print platen  31  and the recording head  16  is moved even in the sub scan direction shown by the arrow  10   b.    
     DESCRIPTION OF REFERENCE SIGNS 
     
         
           10  inkjet printer 
           16  recording head 
           30   a  space (space where gas passes) 
           31  print platen (platen) 
           31   a  supporting surface 
           31   b  through-hole 
           32  print heater (heater) 
           33  fan 
           34  sheet 
           35  roller (winding member) 
           36  spiral spring (biasing member) 
           37  guide member (fixed member) 
           90  recording medium