Patent Publication Number: US-2023152619-A1

Title: Image forming apparatus

Description:
REFERENCE TO RELATED APPLICATIONS 
     This application claims priority from Japanese Patent Application No. 2021-185016 filed on Nov. 12, 2021. The entire content of the priority application is incorporated herein by reference. 
     BACKGROUND ART 
     A related art discloses an example of an image forming apparatus. In the image forming apparatus, a liquid crystal display panel is located on an upper surface of an operation unit cover constituting a part of a housing. 
     The liquid crystal display panel has a plate shape and including a display surface on an upper surface, and is inclined such that a front end edge is located below a rear end edge. The liquid crystal display panel performs display. 
     An operation key unit is located in front of the liquid crystal display panel on the upper surface of the operation unit cover. The operation key unit includes a plurality of operation buttons and receives an operation input. 
     DESCRIPTION 
     In the image forming apparatus in the related art, the liquid crystal display panel and the operation key unit are separated from each other. However, in recent years, an image forming apparatus often adopts a configuration in which a display operation panel including a display panel and a touch panel overlapping the display panel from above is located on an upper surface of a housing. 
     Such a display operation panel tends to increase in size in an up-down direction due to an increase in thickness caused by an overlap between the display panel and the touch panel. 
     The present disclosure has been made in view of the above circumstances in the related art, and an object thereof is to provide an image forming apparatus reducing an increase in size of a display operation panel in an up-down direction. 
     An image forming apparatus includes: an image forming unit including a photosensitive drum; a housing configured to house the image forming unit; and a display operation panel located on an upper surface of the housing, in which the display operation panel includes: a display panel having a plate shape, including a display surface on an upper surface of the display panel, and being inclined such that a front end edge of the display panel is located below a rear end edge of the display panel; and a touch panel having a plate shape thinner than the display panel, including a touch surface on an upper surface of the touch panel, being inclined such that a front end edge of the touch panel is located below a rear end edge of the touch panel, and overlapping the display panel from above, the touch surface includes: a first region overlapping the display surface and configured to receive an input operation with respect to the touch panel; and a second region not overlapping the display surface and configured to receive the input operation with respect to the touch panel, and the front end edge of the display panel is located behind and above the front end edge of the touch panel such that the second region is located in front of and below the first region. 
     An image forming apparatus includes: an image forming unit including a photosensitive drum; a housing configured to house the image forming unit; and a display operation panel located on an upper surface of the housing, in which the operation panel includes: a display panel having a plate shape and including a display surface on an upper surface of the display panel; and a touch panel having a plate shape, including a touch surface on an upper surface of the touch panel, and overlapping the display panel from above, the touch panel includes: a first region overlapping the display surface and configured to receive an input operation with respect to the touch panel; and a second region located below the first region, not overlapping the display surface, and configured to receive the input operation with respect to the touch panel, and the second region of the touch panel is located below the upper surface of the housing. 
     In the image forming apparatus according to the present disclosure, the display panel thicker than the touch panel is located on an upper portion of the display operation panel, and only the touch panel is located on a lower portion of the display operation panel. As a result, in the image forming apparatus, it is possible to reduce a thickness of the lower portion of the display operation panel as compared with a configuration in which the display panel and the touch panel overlap each other even in the lower portion of the display operation panel. 
     Therefore, in the image forming apparatus according to the present disclosure, it is possible to prevent an increase in size of the display operation panel in the up-down direction. As a result, in the image forming apparatus, it is possible to prevent an increase in size of the entire apparatus in the up-down direction. 
    
    
     
         FIG.  1    is a perspective view of an image forming apparatus according to the present disclosure. 
         FIG.  2    is a partial perspective view of the image forming apparatus according to the present disclosure. 
         FIG.  3    is a partial top view of the image forming apparatus according to the present disclosure. 
         FIG.  4    is a partial cross-sectional view taken along line IV-IV of  FIG.  3   . 
         FIG.  5    is an exploded perspective view showing a part of a top cover, first to fourth sealing members, and a touch panel. 
         FIG.  6    is an exploded perspective view showing a film, a metal plate member, and a display panel. 
         FIG.  7    is an exploded perspective view showing a holder and a control board. 
         FIG.  8    is an exploded perspective view showing the first to fourth sealing members, the touch panel, the film, the metal plate member, the display panel, the holder, and the control board. 
         FIG.  9    is a perspective view of the holder. 
     
    
    
     Hereinafter, an exemplary embodiment of the present disclosure will be described with reference to the drawings. 
     Embodiment 
     As shown in  FIG.  1   , an image forming apparatus  1  according to the embodiment is an example of a specific aspect of the image forming apparatus according to the present disclosure. In  FIG.  1   , a front cover  8  side of a housing  9  of the image forming apparatus  1  is a front side. A width direction of the housing  9  is a direction orthogonal to a front-rear direction and extending horizontally. When facing the front cover  8 , a left side is one side in the width direction. Further, directions shown in  FIG.  2    and subsequent drawings are all displayed in correspondence with the directions shown in  FIG.  1   . 
     &lt;Overall Configuration&gt; 
     As shown in  FIG.  1   , the image forming apparatus  1  includes the housing  9 , an image forming unit  5 , a sheet cassette  4 , and a display operation panel  3 . 
     The housing  9  is a substantially box-shaped body. The housing  9  houses the sheet cassette  4  at a lower portion thereof. The sheet cassette  4  supports sheets subjected to image forming in a stacked state. 
     In addition, the housing  9  houses the image forming unit  5  above the sheet cassette  4  inside the housing  9 . The image forming unit  5  forms an image on a sheet conveyed from the sheet cassette  4  by an electrophotographic method, an inkjet method, or the like. The image forming unit  5  using the electrophotographic method includes a photosensitive drum. 
     The housing  9  includes, as an outer cover, a top cover  100 , a front cover  8 , a rear cover  7 , and side covers  6 L and  6 R. The top cover  100  is an example of the “cover” according to the present disclosure. In the present embodiment, each of the top cover  100  and the like is a resin molded product manufactured by injection molding or the like of a thermoplastic resin. 
     The front cover  8  includes a front wall  8 F and an upper wall  8 U. The front wall  8 F is located above a front panel  4 F of the sheet cassette  4 . The front wall  8 F of the front cover  8  and the front panel  4 F of the sheet cassette  4  constitute a front surface of the housing  9 . The upper wall  8 U is connected to an upper end edge of the front wall  8 F, protrudes rearward, and extends in the width direction. The upper wall  8 U constitutes a front end edge side of an upper surface  9 U of the housing  9 . 
     The rear cover  7  constitutes a rear end edge side of the upper surface  9 U of the housing  9 . The side cover  6 L located on the one side in the width direction constitutes a side surface of the housing  9  located on the one side in the width direction. The side cover  6 R located on the other side in the width direction constitutes a side surface of the housing  9  located on the other side in the width direction. 
     A front end edge  100 A of the top cover  100  faces a rear end edge of the upper wall  8 U of the front cover  8 . A rear end edge  100 B of the top cover  100  faces a front end edge of the rear cover  7 . The top cover  100  constitutes the upper surface  9 U of the housing  9  together with the upper wall  8 U of the front cover  8  and the rear cover  7 . 
     The top cover  100  includes a flat surface  100 F that includes the front end edge  100 A and the rear end edge  100 B, and extends substantially horizontally. 
     In addition, the top cover  100  includes a panel housing unit  103  in a portion located in front of the top cover  100  and on the one side in the width direction. The panel housing unit  103  includes a portion protruding upward from the flat surface  100 F and a portion overlapping the flat surface  100 F. 
     The side cover  6 L located on the one side in the width direction includes a bulging portion  6 L 1  located below the panel housing unit  103 . The bulging portion  6 L 1  protrudes to the one side in the width direction along the panel housing unit  103 . 
     A side end edge  100 L of the top cover  100  located on the one side in the width direction and located behind the panel housing unit  103  faces an upper end edge of the side cover  6 L located behind the bulging portion  6 L 1 . A side end edge  100 R of the top cover  100  located on the other side in the width direction faces an upper end edge of the side cover  6 R. 
     The top cover  100  includes a recessed portion  100 D recessed downward from the flat surface  100 F. 
     The housing  9  includes, on the upper surface  9 U thereof, a sheet discharging port  9 H and a discharging tray  9 T. The discharging tray  9 T is a bottom surface of the recessed portion  100 D of the top cover  100 , and is inclined downward and rearward. The sheet discharging port  9 H is located on a rear surface rising from a rear end of the bottom surface of the recessed portion  100 D. 
     The sheet on which an image is formed by the image forming unit  5  is discharged forward from the sheet discharging port  9 H. The discharging tray  9 T supports the sheet discharged from the sheet discharging port  9 H. 
     As shown in  FIGS.  2  to  4   , the display operation panel  3  is housed in the panel housing unit  103  and is located on the upper surface  9 U of the housing  9 . The display operation panel  3  is located at a position shifted to the one side in the width direction with respect to the discharging tray  9 T. A control unit, which is not shown, controls the display operation panel  3  to cause the display operation panel  3  to display various kinds of information such as setting information and an operation status of the image forming unit  5 , and to acquire, from the display operation panel  3 , information on an operation input performed by a user. 
     Next, specific configurations of the panel housing unit  103  and the display operation panel  3  will be described in detail. 
     &lt;Panel Housing Unit&gt; 
     A top portion  103 T of the panel housing unit  103  is a ridge line extending horizontally in the width direction at a position separated upward from the flat surface  100 F of the top cover  100 . 
     As shown in  FIGS.  3  to  5   , the panel housing unit  103  includes a fourth portion  140  behind the top portion  103 T. The fourth portion  140  is inclined downward and rearward in a steep angle from the top portion  103 T, and extends in the width direction. 
     The fourth portion  140  includes a portion protruding to the one side in the width direction from the side end edge  100 L of the top cover  100 , and a portion connected to the flat surface  100 F of the top cover  100 . 
     As shown in  FIGS.  2  to  4   , the panel housing unit  103  includes, between the top portion  103 T and the front end edge  100 A of the top cover  100 , a fifth portion  150 , two first portions  110 L and  110 R, two second portions  120 L and  120 R, and a third portion  130 . 
     The fifth portion  150  includes a fifth upper surface  155 . The fifth upper surface  155  is a flat surface that is gradually inclined downward and forward from the top portion  103 T and extends in the width direction. 
     The first portions  110 L and  110 R are located in front of the fifth portion  150 . Each of the first portions  110 L and  110 R includes a first upper surface  111 . 
     The first upper surface  111  of the first portion  110 L located on the one side in the width direction is connected to one end of the fifth upper surface  155  in the width direction. 
     The first upper surface  111  of the first portion  110 R located on the other side in the width direction is connected to the other end of the fifth upper surface  155  in the width direction. 
     Each of the first upper surfaces  111  is a flat surface that is gradually inclined downward and forward and extends in the width direction. The fifth upper surface  155  and the first upper surfaces  111  are flush with one another. 
     The second portions  120 L and  120 R are located in front of the first portions  110 L and  110 R. Each of the second portions  120 L and  120 R includes a second upper surface  122 . 
     The second upper surface  122  of the second portion  120 L located on the one side in the width direction is connected to the first upper surface  111  of the first portion  110 L and extends forward in a horizontal direction and in the width direction. 
     The second upper surface  122  of the second portion  120 R located on the other side in the width direction is connected to the first upper surface  111  of the first portion  110 R and extends forward in the horizontal direction and in the width direction. 
     The second upper surfaces  122  of the second portions  120 L and  120 R overlap the flat surface  100 F. 
     The third portion  130  is located in front of the second portions  120 L and  120 R. The third portion  130  includes a third upper surface  133  and a fourth upper surface  134 . 
     The third upper surface  133  is connected to the second upper surfaces  122  and extends forward in the horizontal direction and in the width direction. The third upper surface  133  overlaps the flat surface  100 F. 
     As shown in  FIGS.  2  to  5   , the fourth upper surface  134  is inclined downward from a rear end edge of the third upper surface  133  located between the second upper surfaces  122 . 
     Further, each of the second portions  120 L and  120 R includes a first side surface  121 . 
     The first side surface  121  of the second portion  120 L extends downward in a vertical direction and in the front-rear direction from a side end edge of the second upper surface  122  of the second portion  120 L located on the other side in the width direction. The first side surface  121  of the second portion  120 L is connected to one end of the fourth upper surface  134  in the width direction. 
     The first side surface  121  of the second portion  120 R extends downward in the vertical direction and in the front-rear direction from a side end edge of the second upper surface  122  of the second portion  120 R located on the one side in the width direction. The first side surface  121  of the second portion  120 R is connected to the other end of the fourth upper surface  134  in the width direction. 
     The panel housing unit  103  has a panel opening  103 H. The panel opening  103 H is a rectangular opening surrounded by the fifth upper surface  155 , the first upper surfaces  111 , the first side surfaces  121 , and the fourth upper surface  134 . 
     &lt;Display Operation Panel&gt; 
     As shown in  FIGS.  4  to  8   , the display operation panel  3  includes first to fourth sealing members  81  to  84 , a touch panel  10 , a film  19 , a metal plate member  20 , a display panel  30 , a holder  70 , and a control board  50  in this order from top to bottom. 
     &lt;Display Panel&gt; 
     As shown in  FIG.  8   , the display panel  30  has a substantially rectangular flat plate shape, and includes a substantially rectangular display surface  31  on an upper surface  30 U. In the present embodiment, the display panel  30  is a liquid crystal display, and includes a backlight, which is not shown, below the display surface  31 . 
     As shown in  FIG.  4   , the display panel  30  is inclined such that a front end edge  30 A is located below a rear end edge  30 B. 
     &lt;Metal Plate Member&gt; 
     As shown in  FIGS.  6  and  8   , the metal plate member  20  is manufactured by punching and bending a thin steel plate. The metal plate member  20  has a rectangular hole larger than an outer shape of the display panel  30 , and includes a plurality of locking pieces  21 A to  21 G protruding downward from an inner circumferential edge surrounding the rectangular hole. 
     As shown in  FIG.  4   , the metal plate member  20  comes into contact with the front end edge  30 A, the rear end edge  30 B, and a pair of side end edges of the display panel  30  in a state where the locking pieces  21 A to  21 G are elastically deformed, to sandwiches the display panel  30 . In this state, an upper surface of the metal plate member  20  is substantially flush with the display surface  31 . 
     &lt;Film&gt; 
     As shown in  FIGS.  6  and  8   , the film  19  is a substantially rectangular resin thin film having a certain degree of rigidity. The film  19  has a rectangular hole slightly larger than the outer shape of the display panel  30 , and a plurality of marks  19 M are printed, on the film  19 , below the rectangular hole. 
     Although not shown, each mark  19 M is designed such that the user can easily determine that the mark  19 M is a button display corresponding to a specific operation input. As shown in  FIG.  4   , the film  19  overlaps the metal plate member  20  from above. The film  19  exposes the display surface  31  through the rectangular hole. 
     &lt;Holder&gt; 
     As shown in  FIGS.  7 ,  8 , and  9   , the holder  70  is a resin molded product manufactured by injection molding or the like of a thermoplastic resin. 
     As shown in  FIG.  7   , a lower surface  70 D of the holder  70  includes a substantially horizontal surface including lower ends of a plurality of ribs connected to one another in a lattice shape, a stepped surface having a step on the horizontal surface, and the like. 
     As shown in  FIG.  9   , the holder  70  includes four screw holes  70 H. As shown in  FIG.  5   , the panel housing unit  103  includes four bosses  107  on a lower surface thereof. As shown in  FIG.  4   , four screws  70 S pass through the respective screw holes  70 H from below and are screwed into the respective bosses  107 , whereby the holder  70  is fastened to the panel housing unit  103 . 
     As shown in  FIGS.  8  and  9   , an upper surface  70 U of the holder  70  is inclined such that a front end edge  70 UA is located below a rear end edge  70 UB. The holder  70  includes a support surface  73  on the upper surface  70 U. The support surface  73  is a bottom surface of a recessed portion recessed one step lower than the front end edge  70 UA and the rear end edge  70 UB of the upper surface  70 U. 
     As shown in  FIG.  4   , the support surface  73  is inclined along a lower surface  30 D of the display panel  30 . The holder  70  supports the display panel  30  from below by the support surface  73 . 
     As shown in  FIGS.  4  and  7   , the holder  70  includes a contact portion  79  located below the support surface  73 . The contact portion  79  extends downward in a tapered cylindrical shape from substantially the center of the support surface  73 , and protrudes downward in a cylindrical shape from substantially the center of the lower surface  70 D. A lower end  79 D of the contact portion  79  is closed. 
     As shown in  FIG.  4   , the image forming apparatus  1  further includes a frame  90  in the housing  9 . Although not shown, the frame  90  is located between the side cover  6 L and the image forming unit  5  in the width direction and extends in the front-rear direction and an up-down direction. The frame  90  supports the image forming unit  5 . 
     The frame  90  includes a convex portion  97  on an upper surface thereof. The convex portion  97  protrudes upward directly below the contact portion  79 . The lower end  79 D of the contact portion  79  is slightly separated upward from an upper end of the convex portion  97 , and is configured to come into contact with the convex portion  97 . 
     The lower end  79 D of the contact portion  79  is displaced downward by a downward force acting on the support surface  73  in a case where the touch panel  10  is pressed down in a first region A 1  of the touch surface  11 , which will be described later, and comes into contact with the convex portion  97  of the frame  90  from above. 
     The holder  70  includes a holding portion  75  on the lower surface  70 D. The holding portion  75  includes front end locking pieces  75 A and  75 B and a positioning shaft  75 C which are located in front of the contact portion  79 , and a positioning shaft  75 D and fitting claws  75 E and  75 F which are located behind the contact portion  79 . 
     &lt;Control Board&gt; 
     As shown in  FIGS.  7  and  8   , the control board  50  is an electric circuit board that controls the display operation panel  3 . The control board  50  acquires, from the control unit, which is not shown, various kinds of information such as the setting information and the operation status of the image forming unit  5 , controls a display operation of the display panel  30 , and cause the display surface  31  to display the information. In addition, the control board  50  controls the touch panel  10 , acquires the information on the operation input by the user, and transmits the information to the control unit, which is not shown. 
     The control board  50  has a flat plate shape including a plurality of recesses and notches. The control board  50  has a circular opening  50 H substantially at the center thereof In addition, the control board  50  includes a positioning recessed portion  50 C at a front end thereof and a positioning hole  50 D at a rear end thereof. 
     As shown in  FIG.  7   , the holding portion  75  holds the control board  50  in the following manner. That is, an assembly worker brings about a state where the control board  50  is located below the lower surface  70 D of the holder  70  and a state where the contact portion  79  passes through the opening  50 H. 
     Next, the assembly worker brings about a state where the front end of the control board  50  is higher than the rear end thereof, the front end locking pieces  75 A and  75 B lock the front end of the control board  50 , and the positioning shaft  75 C is fitted into the positioning recessed portion  50 C. 
     Further, the assembly worker bring about a state where the rear end of the control board  50  is lifted to the same height as the front end thereof, the fitting claws  75 E and  75 F, which are snap-fits, are fitted to the rear end of the control board  50 , and the positioning shaft  75 D is fitted into the positioning hole  50 D. 
     As a result, as shown in  FIG.  4   , the control board  50  comes into contact with the lower surface  70 D from below at a position below the display panel  30 , and extends in the horizontal direction. In this state, the contact portion  79  protrudes downward to a position below the control board  50 . 
     &lt;First Cable of Display Operation Panel and Connector of Control Board&gt; 
     As shown in  FIGS.  6  and  8   , the display operation panel  3  includes a cable  35 . In the present embodiment, the cable  35  is a flexible printed circuit (FPC) in which wiring is printed on a board made of a flexible film or the like. 
     The cable  35  includes one end  35 A and the other end  35 B. The one end  35 A of the cable  35  is connected to the center of the display panel  30  in the width direction on a front end edge  30 A side. The cable  35  protrudes forward and downward from the one end  35 A, and further extends rearward to the other end  35 B. 
     The control board  50  includes a connector  53 . The connector  53  is located on a lower surface of a portion of the control board  50 , the portion being recessed rearward from the center of the front end in the width direction. 
     As shown in  FIG.  4   , the connector  53  is located behind and below the front end edge  30 A of the display panel  30  in the front-rear direction. The other end  35 B of the cable  35  is located below and behind the one end  35 A. The other end  35 B of the cable  35  is fitted into the connector  53 , thereby being connected to the control board  50 . 
     As shown in  FIGS.  4  and  7   , the control board  50  includes a connector  54  on a rear end edge side thereof. The connector  54  is fitted with one end of a cable, which is not shown, that connects the control board  50  and the control unit, which is not shown. 
     &lt;Touch Panel&gt; 
     As shown in  FIG.  8   , the touch panel  10  has a substantially rectangular flat plate shape and includes the substantially rectangular touch surface  11  on an upper surface  10 U. The touch panel  10  is a user interface that determines which position on the touch surface  11  a finger or the like of the user touched by, for example, an electrostatic capacitance method or a resistive film method. 
     A length of the touch surface  11  in the width direction is slightly larger than a length of the display surface  31  in the width direction. On the other hand, a length of the touch surface  11  in the front-rear direction is significantly larger than a length of the display surface  31  in the front-rear direction. 
     A side end edge of the touch panel  10  located on the one side in the width direction is referred to as a first side end edge  10 L. A side end edge of the touch panel  10  located on the other side in the width direction is referred to as a second side end edge  10 R. 
     As shown in  FIG.  4   , the touch panel  10  is inclined such that the front end edge  10 A is located below the rear end edge  10 B. The touch panel  10  overlaps the display panel  30  from above. In this state, the display surface  31  and the touch surface  11  are parallel to each other. 
     The front end edge  70 UA of the upper surface  70 U of the holder  70  supports the front end edge  10 A of the touch panel  10  with the front end edges of the film  19  and the metal plate member  20  interposed therebetween. 
     The rear end edge  70 UB of the upper surface  70 U of the holder  70  supports the rear end edge  10 B of the touch panel  10  with the rear end edges of the film  19  and the metal plate member  20  interposed therebetween. 
     The touch panel  10  is thinner than the display panel  30 . In the present embodiment, a thickness of the touch panel  10  is less than half of a thickness of the display panel  30 . 
     As shown in  FIGS.  3  and  4   , the panel housing unit  103  covers the front end edge  10 A, the rear end edge  10 B, the first side end edge  10 L, and the second side end edge  10 R of the touch panel  10 , and expose the touch surface  11  through the panel opening  103 H. 
     More specifically, the third portion  130  covers the front end edge  10 A of the touch panel  10  with the fourth upper surface  134  that is inclined downward toward the touch surface  11 . 
     The fifth portion  150  covers the rear end edge  10 B of the touch panel  10  with the fifth upper surface  155 . 
     The two first portions  110 L and  110 R cover the first side end edge  10 L and the second side end edge  10 R of the touch panel  10  with the respective first upper surfaces  111 . 
     The two second portions  120 L and  120 R cover the first side end edge  10 L and the second side end edge  10 R of the touch panel  10  with the respective second upper surfaces  122  and the respective first side surfaces  121 . 
     As shown in  FIG.  4   , the fifth upper surface  155  and the first upper surface  111  are inclined along the touch panel  10 . 
     &lt;First Region and Second Region of Touch Surface&gt; 
     As shown in  FIGS.  2  and  4   , the touch surface  11  includes the first region A 1  and a second region A 2 . 
     As shown in  FIG.  4   , the first region A 1  is a region overlapping the display surface  31  and configured to receive an input operation with respect to the touch panel  10 , in which the display panel  30  displays in the first region A 1 . 
     A front end A 1 A of the first region A 1  coincides with a front end of the display surface  31 . A rear end A 1 B of the first region A 1  coincides with a rear end of the display surface  31 . 
     The second region A 2  is a region not overlapping the display surface  31  and configured to receive the input operation with respect to the touch panel  10 , in which the display panel  30  does not display in the second region A 2 . A rear end of the second region A 2  is in contact with the front end A 1 A of the first region A 1 . 
     As shown in  FIG.  2   , the user can visually recognize each mark  19 M printed on the film  19  in the second region A 2 , and performs an operation input of bringing a finger or the like into contact with one of the marks  19 M. The plurality of marks  19 M are located under the second region A 2  of the touch panel  10 . 
     As shown in  FIG.  4   , the front end edge  30 A of the display panel  30  is located behind and above the front end edge  10 A of the touch panel  10  such that the second region A 2  is located in front of and below the first region A 1 . The second region A 2  is located below the upper surface  9 U of the housing  9 . 
     As shown in  FIG.  2   , a connection point between the first upper surface  111  of the first portion  110 L and the second upper surface  122  of the second portion  120 L is defined as J 1 L. A connection point between the first upper surface  111  of the first portion  110 R and the second upper surface  122  of the second portion  120 R is defined as J 1 R. 
     As shown in  FIG.  4   , a virtual plane VP 1 , which extends in the width direction of the housing  9 , passes through two connection points J 1 L and J 1 R between the respective first upper surfaces  111  and the respective second upper surfaces  122 , and is orthogonal to the touch surface  11 , is set. 
     The front end A 1 A of the first region A 1  of the touch surface  11  is located closer to a rear end edge  10 B side of the touch panel  10  than the virtual plane VP 1 . In other words, in a case where the two connection points J 1 L and J 1 R are virtually projected onto the touch surface  11  in a direction orthogonal to the touch surface  11 , the front end A 1 A of the first region A 1  of the touch surface  11  is located closer to the rear end edge  10 B side than the two projected connection points J 1 L and J 1 R, that is, located above and behind the two projected connection points J 1 L and J 1 R. 
     &lt;First to Fourth Sealing Members&gt; 
     As shown in  FIGS.  5  and  8   , each of the first to fourth sealing members  81  to  84  is made of an easily elastically deformable material such as a soft rubber, an elastomer, or a foam material having closed cells. The first sealing member  81  and the second sealing member  82  linearly extend in the front-rear direction. The third sealing member  83  and the fourth sealing member  84  linearly extend in the width direction. 
     As shown in  FIG.  3   , the first sealing member  81  is located on the one side in the width direction with respect to the panel opening  103 H. The first sealing member  81  seals a gap between the first side end edge  10 L of the touch panel  10  and the panel housing unit  103 . 
     The second sealing member  82  is located on the other side in the width direction with respect to the panel opening  103 H. The second sealing member  82  seals a gap between the second side end edge  10 R of the touch panel  10  and the panel housing unit  103 . 
     As shown in  FIGS.  3  and  4   , the third sealing member  83  is located in front of the panel opening  103 H. The third sealing member  83  seals a gap between the front end edge  10 A of the touch panel  10  and the panel housing unit  103 . 
     The fourth sealing member  84  is located behind the panel opening  103 H. The fourth sealing member  84  seals a gap between the rear end edge  10 B of the touch panel  10  and the panel housing unit  103 . 
     A positional relation of the first to fourth sealing members  81  to  84  with respect to the holder  70  is indicated by a two-dot chain line in  FIG.  9   . The first sealing member  81  and the third sealing member  83  have a joint S 1 . The second sealing member  82  and the third sealing member  83  have a joint S 2 . 
     &lt;Groove and Communication Hole of Holder&gt; 
     As shown in  FIG.  9   , the holder  70  includes grooves  71  and  72  and communication holes  71 H and  72 H. 
     One end of the groove  71  is recessed downward in front of an end portion of the front end edge  70 UA of the upper surface  70 U on the one side in the width direction. In addition, the one end of the groove  71  is located in front of the joint S 1  between the first sealing member  81  and the third sealing member  83 . 
     The groove  71  extends a short distance forward from the one end, then bends, extends toward the other side in the width direction, and reaches the other end. The other end of the groove  71  is connected to the communication hole  71 H. A liquid spilling on the touch surface  11  and entering the housing  9  from the joint S 1  moves on the groove  71  along a dashed arrow Y 1 , passes through the communication hole  71 H, and drips down. 
     One end of the groove  72  is recessed downward in front of an end portion of the front end edge  70 UA of the upper surface  70 U on the other side in the width direction. In addition, the one end of the groove  72  is located in front of the joint S 2  between the second sealing member  82  and the third sealing member  83 . 
     The groove  72  extends a short distance from the one end toward one side in the width direction, then bends, extends forward, and reaches the other end. The other end of the groove  72  is connected to the communication hole  72 H. Liquid spilling on the touch surface  11  and entering the housing  9  from the joint S 2  moves on the groove  72  along a dashed arrow Y 2 , passes through the communication hole  72 H, and drips down. 
     As shown in  FIG.  4   , the frame  90  includes a groove  96  that is recessed downward directly below the groove  71  of the holder  70 . The groove  96  extends in the width direction and is located directly below the communication holes  71 H and  72 H. The groove  96  stores the liquid dripping from the communication holes  71 H and  72 H and guides the liquid toward the side cover  6 L. 
     In this way, the grooves  71  and  72  of the holder  70  cooperate with the groove  96  of the frame  90  to guide the liquid entering from the joints S 1  and S 2  to be away from the image forming unit  3 . 
     &lt;Operation and Effect&gt; 
     In the image forming apparatus  1  according to the embodiment, as shown in  FIG.  4   , the display panel  30  thicker than the touch panel  10  is biased to an upper portion of the display operation panel  3 , and only the touch panel  10  exists in a lower portion of the display operation panel  3 . As a result, in the image forming apparatus  1 , it is possible to reduce a thickness of the lower portion of the display operation panel  3  as compared with a configuration in which the display panel  30  and the touch panel  10  overlap each other even in the lower portion of the display operation panel  3 . 
     Therefore, in the image forming apparatus  1  according to the embodiment, it is possible to reduce an increase in size of the display operation panel  3  in the up-down direction. As a result, in the image forming apparatus  1 , it is possible to prevent an increase in size of the entire apparatus in the up-down direction. 
     In addition, in the image forming apparatus  1 , as shown in  FIG.  2   , the panel housing unit  103  includes the first portions  110 L and  110 R and the second portions  120 L and  120 R. The connection point between the first upper surface  111  of the first portion  110 L and the second upper surface  122  of the second portion  120 L is defined as J 1 L. The connection point between the first upper surface  111  of the first portion  110 R and the second upper surface  122  of the second portion  120 R is defined as J 1 R. As shown in  FIG.  4   , the virtual plane VP 1  is set that extends in the width direction of the housing  9 , passes through the two connection points J 1 L and J 1 R between the respective first upper surfaces  111  and the respective second upper surfaces  122 , and is orthogonal to the touch surface  11 . The front end A 1 A of the first region A 1  of the touch surface  11  is located closer to the rear end edge  10 B side of the touch panel  10  than the virtual plane VP 1 . With this configuration, the user can easily recognize the front end A 1 A of the first region A 1  for display and operation input with reference to the two connection points J 1 L and J 1 R. 
     Further, in the image forming apparatus  1 , the panel housing unit  103  further includes the third portion  130  including the third upper surface  133  and the fourth upper surface  134 . With this configuration, the second portions  120 L and  120 R and the third portion  130  can suitably expose the second region A 2  of the touch surface  11  below the second upper surface  122  and the third upper surface  133 . 
     In addition, in the image forming apparatus  1 , the display operation panel  3  includes the cable  35  and the control board  50  located below the display panel  30 . The cable  35  includes the one end  35 A connected to the front end edge  30 A side of the display panel  30  and the other end  35 B located below and behind the one end  35 A and connected to the control board  50 , protrudes forward and downward from the one end  35 A, and further extends rearward to the other end  35 B. With this configuration, an empty space below the touch panel  10  existing in the lower portion of the display operation panel  3  can be effectively used as a space for the cable  35  to make a U-turn. 
     Further, in the image forming apparatus  1 , the control board  50  includes the connector  53  into which the other end  35 B of the cable  35  is fitted, and extends in the horizontal direction. The connector  53  is located behind and below the front end edge  30 A of the display panel  30  in the front-rear direction. With this configuration, since the U-turn of the cable  35  becomes gentle as compared with a case where the control board  50  is inclined along the display panel  30 , an operation of fitting the other end  35 B of the cable  35  into the connector  53  of the control board  50  can be easily implemented. In addition, since the rear end edge  30 B of the display panel  30  and the rear end edge of the control board  50  are largely separated from each other in the up-down direction, an operation of fitting one end of the cable that is not shown into the connector  54  located on a rear end edge side of the control board  50  can be easily implemented without being affected by the rear end edge  30 B of the display panel  30 . 
     In addition, in the image forming apparatus  1 , the lower end  79 D of the contact portion  79  of the holder  70  is displaced downward by a downward force acting on the support surface  73  in a case where the touch panel  10  is pressed down in the first region A 1  of the touch surface  11 , and comes into contact with the convex portion  97  of the frame  90  from above. With this configuration, the frame  90  can effectively support the force of pressing the touch panel  10  via the support surface  73  and the contact portion  79 . As a result, the image forming apparatus  1  can prevent the touch panel  10  from being damaged. 
     Further, in the image forming apparatus  1 , as shown in  FIG.  7   , the holder  70  includes, on the lower surface  70 D, the holding portion  75  that holds the control board  50 . As shown in  FIG.  4   , the contact portion  79  protrudes downward to a position below the control board  50 , and the lower end  79 D is contactable with the frame  90  from above. The control board  50  includes the opening  50 H through which the contact portion  79  passes. With such an opening  50 H, the layout flexibility of the contact portion  79  and the control board  50  can be improved. 
     In addition, in the image forming apparatus  1 , as shown in  FIG.  9   , the holder  70  includes the groove  71  that guides the liquid entering from the joint S 1  between the first sealing member  81  and the third sealing member  83 . In addition, the holder  70  includes the groove  72  that guides the liquid entering from the joint S 2  between the second sealing member  82  and the third sealing member  83 . Further, the holder  70  includes the communication hole  71 H connected to the other end of the groove  71  and the communication hole  72 H connected to the other end of the groove  72 . The frame  90  includes the groove  96  that stores the liquid dripping from the communication holes  71 H and  72 H and guides the liquid toward the side cover  6 L. With this configuration, it is possible to prevent the occurrence of a defect in the image forming unit  5  due to the liquid entering from the joint S 1  between the first sealing member  81  and the third sealing member  83 , and the joint S 2  between the second sealing member  82  and the third sealing member  83 . 
     Although the present disclosure has been described with reference to the embodiment, it is needless to say that the present disclosure is not limited to the above embodiment and can be appropriately modified and applied without departing from the gist thereof. 
     In the embodiment, the display panel  30  is a liquid crystal display, but the present disclosure is not limited to this configuration. For example, the display panel may be an organic EL display. 
     In the embodiment, the contact portion  79  has a cylindrical shape in which the lower end  79 D is closed, but the present disclosure is not limited to this configuration. For example, the contact portion may be a rib, a columnar protrusion, or the like. 
     In the embodiment, the rear end of the second region A 2  is in contact with the front end A 1 A of the first region A 1 , but the present disclosure is not limited to this configuration. For example, the rear end of the second region may be separated from the front end of the first region A 1 . 
     In the embodiment, the opening  50 H of the control board  50  is a hole, but the present disclosure is not limited to this configuration. For example, the opening of the control board  50  may be a notch or the like. 
     In the embodiment, the cable  35  is a flexible printed circuit, but the present disclosure is not limited to this configuration. For example, the cable may be a flexible flat cable. 
     In the embodiment, the two connection points J 1 L and J 1 R, between the respective first upper surfaces  111  and the respective second upper surfaces  122 , extend in the width direction of the housing  9  and are formed in an angled and recessed shape, but the present disclosure is not limited to this configuration. For example, the two connection points J 1 L and J 1 R may be connected to be continuous in an R shape. In this case, as the connection points J 1 L and J 1 R, for example, virtual portions intersecting in a case where the first upper surfaces  111  and the second upper surfaces  122  are virtually continuous may be regarded as the connection points J 1 L and J 1 R, and a position of the front end A 1 A of the first region A 1  of the touch surface  11  may be set with reference to the regarded connection points J 1 L and J 1 R. A connection point between the first upper surface  111  and the R shape or a connection point between the second upper surface  122  and the R shape may be regarded as the connection points J 1 L and J 1 R. 
     The present disclosure is applicable to, for example, an image forming apparatus or a multifunction machine having a printer function and a scanner function.