Abstract:
An image display device installed for a rear seat passenger of a vehicle, including: a display section for displaying an image information that includes an image of an outside rear part of the vehicle which is taken with a back camera; and a driving sensor for detecting that the vehicle is set to a rearward driving mode, wherein when the driving sensor detects the setting of the rearward driving mode, the display section is rotated to allow a driver who turns to a rear side of the vehicle to see the image of the outside rear part of the vehicle.

Description:
CROSS REFERENCE OF RELATED APPLICATION  
       [0001]     This application is based on and claims priority under 35 U.S.C. § 119 with respect to Japanese Patent Application No. 2004-158759 filed on May 28, 2004, the entire content of which is incorporated herein by reference.  
       BACKGROUND OF THE INVENTION  
       [0002]     The present invention relates to an image display device and an installation device thereof.  
         [0003]     These days, a vehicle provided with a monitor system for displaying an output image from a navigation device, a TV tuner, a DVD player, etc., which includes a monitor for a front seat (a front monitor) installed adjacent to a dash board and a monitor for a rear seat (an image display device), has been disclosed in the related art (see JP-A-2004-90722).  
         [0004]     A monitor system  1  described in JP-A-2004-90722 includes a front monitor  3  which is installed adjacent to a dash board  2 , a back camera  5  which is installed on a roof panel above a rear seat  4 , and an image display device  6  which is suspended from the roof panel in front of the rear seat  4 .  
         [0005]     In the monitor system  1 , while a vehicle is in a forward driving mode, an output image from a navigation device, a TV tuner, etc. can be displayed on the front monitor  3  and/or the image display device  6 . Meanwhile, while the vehicle is in a rearward driving mode, an image from the back camera  5  is displayed on the front monitor  3  so that an outside rear part of the vehicle can be checked from the image appearing on the front monitor  3 .  
         [0006]     Further, in the monitor system  1 , while the vehicle travels rearward, the image display device  6  can be received in the roof panel so that the driver can directly view the outside rear part of the vehicle without being obstructed by the image display device  6 .  
         [0007]     As described above, in the conventional monitor system  1  which is provided with the back camera  5  for photographing the outside rear part of the vehicle, when the vehicle travels rearward, the driver can see through the front monitor  3  the image of the outside rear part of the vehicle which is obtained by the back camera  5 .  
         [0008]     In this regard, since the back camera  5  cannot properly photographs a dead spot and limitations necessarily exist in a display window size and a resolution of the front monitor  3 , it is not preferred in view of safety that the driver drives the vehicle rearwards only relying on the image which is obtained by the back camera  5  and displayed on the front monitor  3 .  
         [0009]     For this reason, during rearward driving of the vehicle, while the driver faces forward and sees the front monitor  3  on which the image from the back camera  5  is displayed, it is necessary for the driver to sometimes turn around and directly check the outside rear part of the vehicle through a rear wind shield glass. Therefore, as a procedure in which the driver faces forward and turns around is repeated, difficulties are caused when driving the vehicle rearwards.  
       SUMMARY OF THE INVENTION  
       [0010]     The present invention has been made to solve the problems occurring in the related art, and an object of the present invention is to eliminate the difficulties which are caused when driving a vehicle rearwards due to the fact that a procedure in which a driver sees a front monitor on which an image from a back camera is displayed while facing forward and turns around to directly check an outside over the rear window of the vehicle is repeated.  
         [0011]     According to a first aspect of the invention, there is provided an image display device installed for a rear seat passenger of a vehicle, including: a display section for displaying an image information that includes an image of an outside rear part of the vehicle which is taken with a back camera; and a driving sensor for detecting that the vehicle is set to a rearward driving mode, wherein when the driving sensor detects the setting of the rearward driving mode, the display section is rotated to allow a driver who turns to a rear side of the vehicle to see the image of the outside rear part of the vehicle.  
         [0012]     According to a second aspect of the invention, there is provided an installation device for the image display device of the first aspect of the invention, including: a rotation mechanism for rotating the image display device; and a maintaining member for maintaining the rotation mechanism at a shaft of a headrest of a front seat of the vehicle. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]     These and other objects and advantages of this invention will become more fully apparent from the following detailed description taken with the accompanying drawings in which:  
         [0014]      FIG. 1  is a view illustrating location of a conventional image display device;  
         [0015]      FIG. 2  is a plan view illustrating an image display device and an installation device thereof in accordance with a first embodiment of the present invention;  
         [0016]      FIG. 3  is a perspective view illustrating the image display device and the installation device thereof according to the first embodiment of the present invention;  
         [0017]      FIG. 4  is an exploded view illustrating a main part of the image display device installation device according to the first embodiment of the present invention;  
         [0018]      FIG. 5  is a perspective view illustrating an image display device and an installation device thereof in accordance with a second embodiment of the present invention; and  
         [0019]      FIG. 6  is an exploded view illustrating a main part of the image display device installation device according to the second embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0020]     Hereafter, an image display device and an installation device thereof in accordance with preferred embodiments of the present invention will be described with reference to the attached drawings.  
       First Embodiment  
       [0021]     Referring to  FIG. 2 , a monitor system  10  provided to a vehicle  11  includes an image display device  17  which is installed to the seat back  15  of a front passenger seat  14  through an image display device installation device  16 , and a back camera  19  which is installed (for example, on a roof panel behind a rear seat  18 ) to photograph an outside rear part of the vehicle  11 . That is to say, the monitor system  10  in accordance with a first embodiment of the present invention as shown in  FIG. 2  includes the image display device  17  and the installation device  16  thereof.  
         [0022]     The monitor system  10  further includes a controller  12  for controlling display of an image from the back camera  19  and operation of a rotation mechanism  22 .  
         [0023]     A general front monitor  13  for displaying an output image from a navigation device, a TV tuner, a DVD player, etc. may be provided in front of a driver seat  20 .  
         [0024]     In the first embodiment of the present invention, the image display device installation device  16  is positioned at least more rearward than the driver seat  20  and includes the rotation mechanism  22  (see  FIGS. 3 and 4 ) for rotating the image display device  17  to allow a display section  21  (see  FIG. 3 ) of the image display device  17  to be seen from the driver seat  20  when a driver turns around.  
         [0025]     A concrete example of the image display device installation device  16  will be described below. Referring to  FIG. 3 , a stay  24  is placed on the upper end  15   a  of the seat back  15  of the front passenger seat  14 . The stay  24  is defined with a pair of holes  25 . By respectively inserting a pair of shafts  27  of a headrest  26  through the pair of holes  25  of the stay  24 , the stay  24  is installed on the upper end  15   a  of the seat back  15 . An arm  28  is coupled to the stay  24 , and the image display device  17  is installed to the distal end  28   a  of the arm  28  so that the image display device  17  can be freely rotated in directions shown by the arrows through the operation of the rotation mechanism  22 .  
         [0026]     As shown in  FIG. 4 , in the rotation mechanism  22 , an insertion groove  31  is defined on the lower surface  29  of the image display device  17  in a manner such that an inner surface  31   a  which extends from a lowermost opening  31   b  of the insertion groove  31  to the bottom  31   c  of the insertion groove  31  is diverged. The rotation mechanism  22  includes an insertion part  33  which is inserted into the insertion groove  31 . The edge of the insertion part  33  is formed as an inclined outer surface  33   a  in conformity with the inner surface  31   a  of the insertion groove  31 . Due to this fact, when the insertion part  33  is inserted into the insertion groove  31 , the insertion part  33  can be securely held in the insertion groove  31 . A rod  34  is connected to the insertion part  33 . The rod  34  is rotatably coupled to a support rod  35  which is installed to the distal end  28   a  (see  FIG. 3 ) of the arm  28 .  
         [0027]     Terminals  37  serving as electrical contacts are placed on the bottom  31   c  of the insertion groove  31 , and a surface  33   b  of the insertion part  33  which faces the bottom  31   c  of the insertion groove  31  is provided with contacts (not shown) which are brought into electric contact with the terminals  37 .  
         [0028]     Also, instead of arranging the electrical contacts on the bottom  31   c  of the insertion groove  31  and the insertion part  33 , separate electrical wirings such as electric cords (not shown) may be used.  
         [0029]     Due to the provision of the rotation mechanism  22 , the image display device  17 , which is installed at a position where a rear seat passenger can see the display section  21  while facing forward, can be rotated by about 180° so that the display section  21  can be seen by the driver when the driver turns around toward the rear part of the vehicle  11 .  
         [0030]     The display section  21  of the image display device  17  is constructed in a manner such that it can display an image from the back camera  19  which is installed to photograph the outside rear part of the vehicle  11 . As a consequence, when the driver turns around toward the rear part of the vehicle  11 , the driver can see the image from the back camera  19  which is displayed on the display section  21  of the image display device  17 .  
         [0031]     Further, the image display device  17  and the installation device  16  thereof are controlled in their operation by the controller  12  so that, when the vehicle  11  is set to travel rearward, the image from the back camera  19  is displayed on the image display device  17  and the image display device  17  is automatically rotated by about 180° toward the driver to allow the driver who turns around to see the image from the back camera  19 .  
         [0032]     A switch (not shown) for rotating the image display device  17  can be installed at a predetermined position. In this case, before driving the vehicle  11  in a rearward direction, the driver can manipulate the switch to rotate the image display device  17  so that the display section  21  faces the driver in advance. Then, as the vehicle  11  travels rearward, the image from the back camera  19  is displayed on the display section  21 .  
         [0033]     The image display device  17  according to this first embodiment of the present invention is installed for the rear seat passenger of the vehicle  11 . The image display device  17  can display the image from the back camera  19  which is installed to photograph the outside rear part of the vehicle  11  and can allow the driver to see the image from the back camera  19  when the driver turns around toward the rear part of the vehicle  11 . The image display device  17  is constructed to display the image from the back camera  19  when the vehicle  11  is set to a rearward traveling mode.  
         [0034]     Since the image display device  17  of this preferred embodiment can be rotated by about 180°, it is possible to use a monitor display which is provided with the display section  21  only on one surface thereof.  
         [0035]     In this preferred embodiment, because the monitor display can be attached to and detached from the image display device installation device  16 , the existing monitor displays can be freely employed without departing from the scope and spirit of the present invention.  
         [0036]     Also, in the present embodiment, although it becomes impossible to freely attach and detach the monitor display to and from the image display device installation device  16 , it can be envisaged that the insertion groove  31  and the insertion part  33  are integrally constructed with each other, whereby the image display device  17  can be integrated with the image display device installation device  16 .  
         [0037]     Hereafter, operation of the monitor system  10  for the vehicle  11  which includes the image display device  17  and the image display device installation device  16  will be described.  
         [0038]     In the monitor system  10  shown in  FIG. 2 , when the driver moves a shift lever (not shown) to a rearward (backward) driving position, that is, when gear shift to a back gear is effected in a transmission to allow rearward traveling of the vehicle  11 , if an image is not displayed on the image display device  17  (that is, a power switch of the image display device  17  is turned off), the power switch of the image display device  17  is turned on. Then, the image from the back camera  19  is displayed on the image display device  17 .  
         [0039]     When the vehicle  11  is set to travel rearward, in the case that an image from a TV or DVD player is displayed on the image display device  17 , the display of the image from the TV or DVD player is stopped, and instead, the image from the back camera  19  is displayed on the image display device  17 .  
         [0040]     At the same time, as the rotation mechanism  22  is controlled by the controller  12  to be driven, the image display device  17  is automatically rotated by about 180° so that the display section  21  of the image display device  17  faces the driver.  
         [0041]     Therefore, as the driver turns around toward the rear part of the vehicle  11 , the driver can directly check the rear part of the vehicle through a rear wind shield glass  39  (see  FIG. 2 ) while seeing the image from the back camera  19  displayed on the display section  21  of the image display device  17 . In this way, since the driver can drive the vehicle  11  rearward while facing the same rearward direction (toward the rear part of the vehicle  11 ), rearward driving of the vehicle  11  can be easily implemented.  
         [0042]     Meanwhile, if the rearward travel of the vehicle  11  is stopped and the driver moves the shift lever to a forward driving position or a parking position, the display of the image from the back camera  19  on the display section  21  of the image display device  17  is ceased, and the image display device  17  returns to the previous condition before the shift lever is moved to the rearward driving position. Further, the rotation mechanism  22  is driven to automatically rotate the image display device  17  by about 180° so that the display section  21  of the image display device  17  can face the rear seat  18 .  
         [0043]     When actually driving the vehicle  11  rearward (for example, when parking the vehicle  11 ), gear shift manipulation is repeated several times in the forward and rearward directions in a manner such that the shift lever is moved to the forward driving position for a little while to allow the vehicle  11  to be slightly moved forward, and then, the shift lever is moved to the rearward driving position to allow the vehicle  11  to be moved rearward to be properly parked in a parking lot. At this time, since switching of the image display of the image display device  17  and operation of the rotation mechanism  22  are continuously repeated, operational reliability of the monitor system  10  can be deteriorated. In this consideration, in the present invention, the monitor system  10  can be controlled in a manner such that, only when a speed of the vehicle  11  exceeds a predetermined speed (or a predetermined time is lapsed) after the shift lever is moved to the forward driving position, the display condition of the image display device  17  can return to an original state and the image display device  17  can be rotated to allow the display section  21  of the image display device  17  to face rearward.  
         [0044]     Also, the display of the image from the back camera  19  and the rotation of the image display device  17  can be implemented after the rearward travel of the vehicle  11  is sensed. For example, when the rearward travel of the vehicle  11  is sensed using a sensor for sensing a rotating direction or a speed of a wheel of the vehicle  11 , the display of the image from the back camera  19  and the rotation of the image display device  17  can be implemented.  
         [0045]     Moreover, the rotation mechanism  22  for rotating the image display device  17  can be constructed to manually rotate the image display device  17 . In this case, before driving the vehicle  11  rearward, it is necessary to manually rotate the image display device  17  so that the display section  21  of the image display device  17  faces the driver seat  20 . Also, it can be envisaged that switching (turning-on or turning-off of the display of the image from the back camera  19 ) the display state of the display section  21  is effected through manipulation of a manual switch (not shown) by the driver.  
       Second Embodiment  
       [0046]     Next, an image display device  52  and an image display device installation device  51  in accordance with a second embodiment of the present invention will be described with reference to  FIGS. 5 and 6 . In this second embodiment of the present invention, the component parts which are the same as those of the first embodiment will be designated by the same reference numerals as those of the first embodiment.  
         [0047]     A monitor system  50  according to this second embodiment is constructed in the same manner as the monitor system  10  according to the first embodiment aforementioned above, except a structure by which an image display device  52  is installed to the seat back  15  of the front passenger seat  14  (see  FIG. 2 ) through an image display device installation device  51 .  
         [0048]     Differently from the image display device  17  of the first embodiment, the image display device  52  of the second embodiment as shown in  FIG. 5  is provided with display sections  53  and  54  on its front and rear surfaces thereof.  
         [0049]     The image display device installation device  51  of the second embodiment is positioned at least rearward of the driver seat  20  (see  FIG. 2 ) and installs the image display device  52  in a manner such that the rear seat passenger seating on the rear seat  18  can see the display section  53  of the image display device  52  and the driver seating on the driver seat  20  can see the display section  54  of the image display device  52  when the driver turns around toward the rear part of the vehicle  11 .  
         [0050]     A concrete example of the image display device installation device  51  will be described below.  
         [0051]     As in the image display device installation device  16  according to the first embodiment as shown in  FIG. 3 , in the image display device installation device  51  according to this second embodiment, a stay  24  is placed on the upper end  15   a  of the seat back  15  of the front passenger seat  14 . The stay  24  is defined with a pair of holes  25 . By respectively inserting a pair of shafts  27  of a headrest  26  through the pair of holes  25  of the stay  24 , the stay  24  is installed on the upper end  15   a  of the seat back  15 . An arm  28  is coupled to the stay  24 .  
         [0052]     Also, in the image display device installation device  51 , as shown in  FIG. 5 , the image display device  52  is installed to the arm  28  through a support mechanism  55 .  
         [0053]     As shown in  FIG. 6 , in the support mechanism  55 , an insertion groove  57  is defined on the side surface  56  of the image display device  52  in a manner such that an inner surface  57   a  which extends from a lowermost opening  57   b  of the insertion groove  57  to the bottom  57   c  of the insertion groove  57  is diverged. The support mechanism  55  includes an insertion part  58  which is inserted into the insertion groove  57 . The edge of the insertion part  58  is formed as an inclined surface  58   a  in conformity with the inner surface  57   a  of the insertion groove  57 . Due to this fact, when the insertion part  58  is inserted into the insertion groove  57 , the insertion part  58  can be securely held in the insertion groove  57 . A support rod  59  is connected to the insertion part  58 . The support rod  59  is installed to the distal end  28   a  (see  FIG. 2 ) of the arm  28 .  
         [0054]     Terminals  61  serving as electrical contacts are placed on the bottom  57   c  of the insertion groove  57 , and a surface  58   b  of the insertion part  58  which faces the bottom  57   c  of the insertion groove  57  is provided with contacts (not shown) which are brought into electric contact with the terminals  61 .  
         [0055]     Also, instead of arranging the electrical contacts on the bottom  57   c  of the insertion groove  57  and the surface  58   b  of the insertion part  58 , separate electrical wirings such as electric cords (not shown) may be used.  
         [0056]     The image display device  52  according to this second embodiment of the present invention is installed for the rear seat passenger of the vehicle  11  and has the display section  53  on one surface which can be seen by the rear seat passenger and the display section  54  on the other surface which can be seen by the driver when the driver turns around.  
         [0057]     In the image display device  52 , the display section  54  facing the driver seat  20  can display the image from the back camera  19  which is installed to photograph the outside rear part of the vehicle  11 . Also, when the driver turns around the rear part of the vehicle  11 , the driver can see the image from the back camera  19  displayed on the display section  54  which faces the driver seat  20 .  
         [0058]     In addition, the image display device  52  is constructed so that, when the vehicle  11  is set to the rearward traveling mode, the image from the back camera  19  can be automatically displayed on the display section  54  which can be seen by the driver.  
         [0059]     Due to the fact that the image from the back camera  19  can be automatically displayed on the display section  54  which can be seen by the driver, the driver can concentrate attention on driving.  
         [0060]     Also, the image display device  52  can be constructed in a manner such that, when it is necessary to drive the vehicle  11  in the rearward direction, a manual switch (not shown) can be manipulated to allow the image from the back camera  19  to be automatically displayed on the display section  54  which can be seen by the driver.  
         [0061]     As in the case of the first embodiment, in the image display device installation device  51  according to this second embodiment, since the monitor display can be freely attached to and detached from the image display device installation device  51 , the existing monitor displays having display sections on both surfaces thereof can be freely employed as the image display device  52  according to this second embodiment of the present invention without departing from the scope and spirit of the present invention.  
         [0062]     Also, in the image display device  52  of the present embodiment, although it becomes impossible to freely attach and detach the monitor display to and from the image display device installation device  51 , it can be envisaged that the insertion groove  57  and the insertion part  58  are integrally constructed with each other, whereby the monitor display can be integrated with the image display device installation device  51 .  
         [0063]     Hereafter, operation of the monitor system  50  for the vehicle  11  which includes the image display device  52  and the image display device installation device  51  will be described.  
         [0064]     In the monitor system  50  shown in  FIGS. 5 and 6 , when the driver moves a shift lever (not shown) to a rearward driving position, that is, when gear shift to a back gear is effected in a transmission to allow rearward traveling of the vehicle  11 , the image from the back camera  19  is displayed on the display section  54  of the image display device  52  which faces the driver seat  20 .  
         [0065]     Therefore, as the driver turns around toward the rear part of the vehicle  11 , the driver can directly check the rear part of the vehicle through a rear wind shield glass  39  (see  FIG. 2 ) while seeing the image from the back camera  19  displayed on the display section  54  of the image display device  52 . In this way, since the driver can drive the vehicle  11  rearward while facing the same rearward direction (toward the rear part of the vehicle  11 ), rearward driving of the vehicle  11  can be easily implemented.  
         [0066]     Meanwhile, if the rearward travel of the vehicle  11  is stopped and the driver moves the shift lever to a forward driving position or a parking position, the display of the image from the back camera  19  on the display section  54  of the image display device  52  is ceased, and the image display device  52  returns to the previous condition before the shift lever is moved to the rearward driving position.  
         [0067]     When actually driving the vehicle  11  rearward (for example, when parking the vehicle  11 ), gear shift manipulation is repeated several times in the forward and rearward directions in a manner such that the shift lever is moved to the forward driving position for a little while to allow the vehicle  11  to be slightly moved forward, and then, the shift lever is moved to the rearward driving position to allow the vehicle  11  to be moved rearward to be properly parked in a parking lot. At this time, since switching of the image display of the image display device  52  is continuously repeated, operational reliability of the monitor system  50  can be deteriorated. In this consideration, in the present invention, the monitor system  50  can be controlled in a manner such that, only when a speed of the vehicle  11  exceeds a predetermined speed (or a predetermined time is lapsed) after the shift lever is moved to the forward driving position, the display condition of the image display device  52  can return to an original state.  
         [0068]     Also, the display of the image from the back camera  19  can be implemented after the rearward travel of the vehicle  11  is sensed. For example, when the rearward travel of the vehicle  11  is sensed using a sensor for sensing a rotating direction or a speed of a wheel of the vehicle  11 , the display of the image from the back camera  19  can be implemented.  
         [0069]     Moreover, it can be envisaged that display switching (turning-on or turning-off of the display of the image from the back camera  19 ) of the display section  54  of the image display device  52  is effected through manipulation of a manual switch (not shown) by the driver.  
         [0070]     In this embodiment of the present invention, since the image display device  52  is provided on both surfaces thereof with the display sections (that is, the display section  53  facing the rear seat  18  and the display section  54  facing the driver seat  20 ), even in the case that an image from a TV or a DVD player is displayed on the display section  53  facing the rear seat  18 , in a state in which the display on the display section  53  can be maintained as it is, the image from the back camera  19  can be displayed on the display section  54 .  
         [0071]     In the first and second embodiments of the present invention, while the back camera  19  is installed as shown in  FIG. 2  to photograph the outside rear part of the vehicle  11 , the back camera  19  can be installed at another place, a photographing direction can be changed, or a plurality of back cameras can be installed so that an image can be appropriately selected. For example, a camera for photographing the front part of the vehicle  11  can be installed, so that, when parking the vehicle in a parking lot, the image from the front camera can be displayed on the image display device  17  and  52 .  
         [0072]     As is apparent from the above description, the image display devices  17  and  52  according to the first and second embodiments which are installed for the rear seat passenger can display the image from the back camera  19  installed to photograph the outside rear part of the vehicle  11  and is constructed to allow the driver to see the image from the back camera  19  when the driver turns around the rear part of the vehicle  11 . Due to this fact, since the image display devices  17  and  52  on which the image from the back camera  19  is displayed are positioned in the same rearward direction toward the rear part of the vehicle  11 , when driving the vehicle  11  in the rearward direction, the driver can drive the vehicle  11  rearward while facing the same rearward direction.