Patent Publication Number: US-2018037115-A1

Title: Display device

Description:
TECHNICAL FIELD 
     The present invention relates to a display device having an opening/closing mechanism of covers. 
     BACKGROUND TECHNIQUE 
     There is known a head-up display device mounted near a driver&#39;s seat of a vehicle. Patent Reference 1 discloses an on-vehicle head-up display device including a combiner for displaying images and a cover. In this head-up display device, when the combiner is not in use, the cover is covering the combiner from above. On the other hand, when the combiner is in use, the cover is retreated from the space above the combiner, and the combiner stands up to be exposed. 
     PRIOR ART REFERENCES 
     Patent References 
     Patent Reference 1: Japanese Patent Application Laid-Open under No. 2013-154817 (see.  FIGS. 1 and 5 ) 
     SUMMARY OF THE INVENTION 
     Problem to be Solved by the Invention 
     Since the cover of Patent Reference 1 is of a single plate-type and needs to be moved between a stowed state and an exposed state of the combiner, the area for arranging the cover requires an area of at least twice the cover. The area in front of the driver&#39;s seat of the vehicle, e.g., the area on the dashboard is limited. Therefore, if the cover occupying such a large area is used, the head-up display device becomes large in size. 
     The above is an example of the problem to be solved by the present invention. It is an object of the present invention to provide a display device which occupies small area by the cover and can be miniaturized as a whole. 
     Means for Solving the Problem 
     An invention described in claims is a display device comprising: a display member configured to display information; a housing configured to receive the display member; an opening formed at one surface of the housing; a plurality of covers movable to vary an opened area of the opening, each of the covers being smaller in area than the opening; and a drive device configured to move the covers, wherein one cover of the plurality of covers is moved by the drive device, and wherein another cover of the plurality of covers is moved by the one cover. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIGS. 1A and 1B  are perspective views illustrating a head-up display according to embodiments. 
         FIG. 2  is a perspective view illustrating an internal structure of the head-up display. 
         FIGS. 3A and 3B  are a plan view and a side view illustrating the internal structure of the head-up display. 
         FIGS. 4A to 4D  illustrate operation when covers are opened in a first embodiment. 
         FIGS. 5A to 5D  illustrate operation when the covers are closed in the first embodiment. 
         FIGS. 6A and 6B  are views for explaining an urging structure by urging springs. 
         FIGS. 7A and 7B  are views for explaining operation of a feed screw receiver. 
         FIGS. 8A to 8D  illustrate operation when the covers are closed in a second embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     According to one aspect of the present invention, there is provided a display device comprising: a display member configured to display information; a housing configured to receive the display member; an opening formed at one surface of the housing; a plurality of covers movable to vary an opened area of the opening, each of the covers being smaller in area than the opening; and a drive device configured to move the covers, wherein one cover of the plurality of covers is moved by the drive device, and wherein another cover of the plurality of covers is moved by the one cover. 
     The above display device displays information by the display member. In the display state, an opening formed on one surface of the housing is opened, and the display member is positioned outside the opening. On the other hand, in the non-display state, the display member is received in the housing, and the opening is closed by the plurality of covers. The plurality of covers are movable to vary an opened area of the opening, and each of the covers is smaller in area than the opening. The drive device switches between the display state and the non-display state by moving the plurality of covers. One cover of the plurality of covers is moved by the drive device, and another cover of the plurality of covers is moved by the one cover. 
     In one mode of the above display device, in a state where the opening is closed by the plurality of covers, the one cover is positioned nearer from a user than the another cover. 
     In another mode of the above display device, in a state where the display member is standing up, the another cover is positioned over the one cover. In still another mode of the above display device, in the state where the display member is standing up, the another cover and the one cover are positioned farther from the user than the display member. 
     In still another mode of the above display device, the housing is formed with first guide grooves at positions corresponding to both sides of the one cover, the housing is formed with second guide grooves at positions corresponding to both sides of the another cover, and the first guide grooves extend to a nearer position to the user than the second guide grooves. 
     In still another mode of the above display device, a projecting part is formed at both ends of the one cover and one end of the another cover, and the projecting part of the another cover engages with the projecting parts of the one cover to move the another cover together with the one cover. 
     In still another mode of the above display device, the drive device comprises: a motor configured to generate driving force by rotation; and a transfer unit configured to transfer the driving force to the covers, and the transfer unit comprises: a plurality of gears configured to transfer the rotation of the motor; and a feed screw configured to rotate by rotation of the gears to move the one cover. In a preferred example, the feed screw is arranged on one side of the plurality of covers, and the one cover is formed with a feed screw receiver on the one side of the plurality of covers, the feed screw receiver being formed with a rack. In a preferred example, the display device further comprises a first urging unit configured to urge the rack in a direction of the feed screw. 
     Still another mode of the above display device further comprises a second urging unit configured to urge the another cover downward. Thus, the another cover moves together with the one cover. 
     In a preferred example, the number of the another cover is one. 
     EMBODIMENTS 
     Preferred embodiments of the present invention will be described below with reference to the attached drawings. 
     1st Embodiment 
       FIGS. 1A and 1B  are perspective views illustrating an appearance of a head-up display (hereinafter referred to as “HUD”)  1  according to a first embodiment of the present invention. It is noted that, when the HUD  1  is mounted on a dashboard of a vehicle, 
     “FRONT” in  FIGS. 1A and 1B  is the side of the front glass of the vehicle, and “REAR” is the side of the seats. Therefore, a user (driver) is positioned on the rear side of the HUD  1 . The rear side in  FIGS. 1A and 1B  is the “near side” from the user, and the front side in  FIGS. 1A and 1B  is the “far side” from the user. 
       FIG. 1A  illustrates a state where covers of the HUD  1  are closed. As shown, the HUD  1  is provided with an opening  2   x  on an upper surface of a housing  2 , and the opening  2   x  is closed by a plurality of covers  3   a  and  3   b.  The covers  3   a  and  3   b  are plate-type covers, respectively. As shown, in the state where the covers are closed, the cover  3   a  is positioned on the nearer side of the user than the cover  3   b.    
     For the sake of convenience, the cover  3   a  will be hereinafter referred to as “the main cover  3   a ”, and the cover  3   b  will be hereinafter referred to as “the sub cover  3   b ”. Also, “the covers  3 ” will be used to simply indicate both the main cover  3   a  and the sub cover  3   b.  The main cover  3   a  corresponds to “one cover” of the present invention, and the sub cover  3   b  corresponds to “another cover” of the present invention. 
     In the state where the opening  2   x  of the housing  2  is closed, the main cover  3   a  and the sub cover  3   b  are aligned in the front-rear direction of the HUD  1  and close the opening  2   x  of the housing  2 . This state is a received state (non-display state) of the HUD  1 . 
       FIG. 1B  illustrates a state where the covers  3  are opened (but the combiner  4  has not stood up yet). When a combiner raising mechanism not shown operates in a state where the opening  2   x  of the housing  2  is opened as shown, the combiner  4  stands up in the opening  2   x.  This state is a display state to display images by the HUD  1 . In the state where the combiner  4  is standing up, the main cover  3   a  and the sub cover  3   b  are positioned on the farther side than the combiner  4  from the user. Also, as shown in  FIG. 5A  described later, in the state where the combiner  4  is standing up, the sub cover  3   b  is positioned over the main cover  3   a.  The combiner  4  is an example of the display member of the present invention. 
     Next, a drive device for opening and closing the covers  3  will be described.  FIG. 2  is a perspective view illustrating an internal structure of the HUD  1 . The drive device is a mechanism to drive the main cover  3   a  and the sub cover  3   b,  and mainly includes a motor  10 , a plurality of gears  11  and a rotatable feed screw  12 . The motor  10  is connected to the feed screw  12  via the gears  11 . The rotation of the motor  10  is transferred to the feed screw  12  via the gears  11  to rotate the feed screw  12 . The gears  11  and the feed screw  12  are the transfer unit of the present invention. 
     A spiral groove  12   x  is formed on the outside of the feed screw  12 . On the other hand, the main cover  3   a  is provided with a feed screw receiver  14  formed with a rack  14   x.  The rack  14   x  of the feed screw receiver  14  engages with the groove  12   x  of the feed screw  12 . When the feed screw  12  is rotated by the rotation of the motor  10 , the rack  14   x  of the feed screw receiver  14  moves along the groove  12   x  of the feed screw  12 . As a result, the main cover  3   a  slides in a direction parallel with the feed screw  12 . The main cover  3   a  is provided with two bearings  15  into which the axis of the feed screw  12  is inserted. 
       FIG. 3A  is a plan view illustrating the internal structure of the HUD  1 , and  FIG. 3B  is a side view illustrating the internal structure of the HUD  1 .  FIGS. 3A and 3B  illustrate the state where the covers  3  are opened. In the state where the covers  3  are opened, the main cover  3   a  is received under the sub cover  3   b.    
     As illustrated in  FIG. 3A , the feed screw  12  is arranged along one side of the main cover  3   a  and the sub cover  3   b.  On the inner walls of the housing  2 , guide grooves  16  are formed on both sides of the main cover  3   a  and the sub cover  3   b.  Specifically, a main cover guide groove and a sub cover guide groove are separately formed. The range of the main cover guide groove is shown by the arrow  16   a,  and the range of the sub cover guide groove is shown by the arrow  16   b.  The main cover guide groove and the sub cover guide groove are formed substantially in parallel with the feed screw  12 . Since the main cover  3   a  is received under the sub cover  3   b  in the state where the covers  3  are opened, the main cover guide groove is formed under the sub cover guide groove. The main cover guide groove and the sub cover guide groove are formed with the lengths corresponding to the moving distances of the main cover  3   a  and the sub cover  3   b  for opening and closing the covers  3 , respectively. As shown by the arrows  16   a  and  16   b,  since the moving distance of the main cover  3   a  is longer than the moving distance of the sub cover  3   b,  the main cover guide groove is longer than the sub cover guide groove and extending to the nearer side of the user. The main cover guide groove corresponds to a first guide groove of the present invention, and the sub cover guide groove corresponds to a second guide groove of the present invention. 
     As illustrated in  FIGS. 2A, 2B, 3A and 3B , projections  17  are formed on the sides of the main cover  3   a  and the sub cover  3   b.  The projections  17  formed on the main cover  3   a  engage with the main cover guide groove, and the projections  17  formed on the sub cover  3   b  engage with the sub cover guide groove. Thus, the main cover  3   a  and the sub cover  3   b  slides along the guide grooves, respectively. 
     As described above, the rotation of the motor  10  is transferred to the main cover  3   a  via the gears  11  and the feed screw  12  to move the main cover  3   a.  On the other hand, the rotation power of the motor  10  is not transferred to the sub cover  3   b,  and the sub cover  3   b  moves to follow the movement of the main cover  3   a.  This will be described in more detail. 
       FIGS. 4A to 4D  are side views schematically illustrating slide movement of the main cover  3   a  and the sub cover  3   b  when the covers  3  are opened.  FIG. 4A  illustrates the state where the covers  3  are closed. The main cover  3   a  and the sub cover  3   b  are aligned in the opening  2   x  of the housing  2  to close the opening  2   x.  One end of the main cover  3   a  is formed with a projecting part  3   ax , and the other end  3   ay  is flat. Also, one end of the sub cover  3   b  is formed with a projecting part  3   bx , and the other end  3   by  is flat. In the closed state of the covers  3 , the end  3   ay  of the main cover  3   a  abuts the end  3   by  of the sub cover  3   b.    
     When the covers  3  are opened, the motor  10  is driven to rotate the feed screw  12 , and the main cover  3   a  is slid in the arrow direction as shown in  FIG. 4B . As the main cover  3   a  is slid, the projecting part  3   ax  of the main cover  3   a  abut the end  3   by  of the sub cover  3   b,  and the end  3   ay  of the main cover  3   a  abut the projecting part  3   bx  of the sub cover  3   b.  Thus, the force that the feed screw  12  slides the main cover  3   a  is transferred to the sub cover  3   b.  Thereby, the sub cover  3   b  slides in the direction of the arrow direction together with the main cover  3   a.  Eventually, as shown in  FIG. 4D , the projecting part  3   bx  of the sub cover  3   b  abuts the inner wall of the housing  2 , and the movement of the main cover  3   a  and the sub cover  3   b  is stopped. In this way, the covers  3  are moved, and the opening  2   x  of the housing  2  is opened. After that, while it is not shown in  FIGS. 4A to 4D , the combiner  4  stands up in the opening  2   x.    
       FIGS. 5A to 5D  are side views schematically illustrating slide movement of the main cover  3   a  and the sub cover  3   b  when the covers  3  are closed.  FIG. 5A  illustrates the state where the covers  3  are opened. First, while it is not shown in  FIGS. 5A to 5D , the combiner  4  that was standing in the opening  2   x  is received in the housing  2 . Next, the motor  10  is driven to rotate the feed screw  12 , and the main cover  3   a  is slid in the arrow direction. At this time, since the sub cover  3   b  is on the main cover  3   a  and the sub cover  3   b  is urged downward by urging springs  13  as described later in detail, the sub cover  3   b  slides in the arrow direction together with the main cover  3   a  as shown in  FIG. 5B . 
     When the main cover  3   a  is slid further, as shown in  FIG. 5C , the sub cover  3   b  moves to the end of its movable range, i.e., the end of the sub cover guiding groove, and stops there. Thereafter, only the main cover  3   a  is further slid in the arrow direction. Then, as shown in  FIG. 5D , the main cover  3   a  moves to the end of its movable range, i.e., the end of the main cover guide groove and stops there. In this way, the opening  2   x  of the housing  2  is closed by the main cover  3   a  and the sub cover  3   b.    
     Next, the urging structure by the urging springs  13  will be described. As shown in  FIG. 3A , the urging springs  13  are provided on both sides of the main cover  3   a  and the sub cover  3   b.    FIG. 6A  illustrates the attached state of the urging spring  13 .  FIG. 6B  is a magnified view of the part of the reference numeral  20  in  FIG. 6A . As shown in  FIGS. 6A and 6B , one end of the urging spring  13  is attached to the end of the sub cover  3   b,  and the other end is attached to the inner wall of the housing  2 . By this, the sub cover  3   b  is urged obliquely downward as indicated by the arrow  21 . While the urging spring  13  is attached to the sub cover  3   b  as shown in  FIG. 6B , a part of the urging spring  13  is hooked on the main cover  3   a  so that the urging force is given to both of the main cover  3   a  and the sub cover  3   b.  Thus, vibration at the time of driving the vehicle can be suppressed. Also, by this urging structure, as described with reference to  FIG. 5B , the main cover  3   a  and the sub cover  3   b  slide integrally. The urging springs  13  are an example of the second urging unit according to the present invention. 
     In the example of  FIGS. 6A and 6B , one end of the urging spring  13  is attached to the sub cover  3   b  and a part of the urging spring  13  is hooked on the main cover  3   a  so that the urging force is given to both of the main cover  3   a  and the sub cover  3   b.  Instead, such a structure can be employed that one end of the urging spring  13  is attached to the main cover  3   a  and a part of the urging spring  13  is hooked on the sub cover  3   b  so that the urging force is given to both the main cover  3   a  and the sub cover  3   b.  Otherwise, urging springs may be separately attached to each of the main cover  3   a  and sub cover  3   b.  In this case, two urging springs are provided on each side of the cover  3 . 
     Next, the feed screw receiver  14  will be described in detail.  FIG. 7A  is a perspective view illustrating the internal structure of the HUD  1 , and  FIG. 7B  is a magnified view of the part of the reference numeral  30  in  FIG. 7A . As shown in  FIG. 7B , the teeth  14   y  of the rack  14  of the feed screw receiver  14  is always pressed against the feed screw  12  by the spring  18 . The cover  3  is positioned to be seen from the driver&#39;s seat, and there is such a concern that the covers  3  may be clogged with a foreign substance at the time of closing. In this view, when a certain load is applied to the covers  3 , the point of the rack  14   x,  i.e., the end on the side of the teeth  14   y  moves in the direction of the arrow  31  with using the fulcrum  14   a  of the rack  14  as the center, and the teeth  14   y  of the rack  14   x  is disengaged from the groove  12   x  of the feed screw  12  so that the covers  3  do not receive force larger than a certain level. Thus, damage caused by the clogging of foreign substances can be prevented. The spring  18  is an example of the first urging unit of the present invention. 
     As described above, in this embodiment, since two covers  3   a  and  3   b  are received in the housing  2  in a stacked manner when the covers  3  are opened, the covers  3   a  and  3   b  do not occupy a large area. Therefore, the device can be miniaturized as a whole. 
     2nd Embodiment 
     In the first embodiment described above, the main cover  3   a  and the sub cover  3   b  are urged by a pair of urging springs  13 . In the second embodiment, the urging springs are omitted. 
       FIGS. 8A to 8D  are side views schematically illustrating slide movement when the main cover  3   a  and the sub cover  3   b  are closed in the second embodiment.  FIG. 8A  illustrates the state where the main cover  3   a  and the sub cover  3   b  are opened. First, while it is not shown in  FIGS. 8A to 8D , the combiner  4  that was standing in the opening  2   x  is received in the housing  2 . Next, the motor  10  is driven to rotate the feed screw  12 , and the main cover  3   a  is slid in the arrow direction. At this time, since the sub cover  3   b  is not urged by the urging springs  13  in the second embodiment, the sub cover  3   b  does not move and only the main cover  3   a  slides in the arrow direction as shown in  FIG. 8B . 
     Then, when the main cover  3   a  slides further and the projecting part  3   ay  of the main cover  3   a  engages with the projecting part  3   bx  of the sub cover  3   b,  the sub cover  3   b  also slides by the movement of the main cover  3   a  as shown in  FIG. 8C . Namely, the sub cover  3   b  moves in the arrow direction in a manner drawn by the main cover  3   a.    
     After that, the sub cover  3   b  moves to the end of the movable range, i.e., the end of the sub cover guide groove and stops there. Thereafter, only the main cover  3   a  slides in the arrow direction. Then, as shown in  FIG. 8D , the main cover  3   a  moves to the end of the movable range, i.e., the end of the main cover guide groove and stops there. In this way, the opening  2   x  of the housing  2  is closed by the covers  3   a  and  3   b.    
     In the second embodiment, the operation of opening the covers  3   a  and  3   b  is the same as that in the first embodiment. 
     INDUSTRIAL APPLICABILITY 
     This invention can be used for a display device having a cover opening/closing mechanism. 
     BRIEF DESCRIPTION OF REFERENCE NUMBERS 
     
         
           1  Head-up Display (HUD) 
           2  Housing 
           3   a,    3   b  Cover 
           4  Combiner 
           10  Motor 
           12  Feed Screw 
           13  Urging Spring 
           14  Feed Screw Receiver