Abstract:
A display apparatus according to the present invention comprises a display part, a housing which accommodates the display part, a circulator circulating the air in the housing around the display part in a vertical direction, and a fan provided on a rear side of the display part. The housing makes the display part be seen from outside therethrough. The fan converts the flow of the air circulating in the vertical direction to a horizontal direction in order to disperse heat generated from a rear surface of the display part.

Description:
[0001]    The Japanese patent application Number 2009-167340, upon which this patent application is based, is hereby incorporated by reference. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a display apparatus with a flat image display panel. 
         [0004]    2. Description of Related Art 
         [0005]    In recent years, flat panel display apparatuses for outdoor installation have appeared. In the apparatus, in order to protect the panel from weather, dust and the like, there has been considered to provide the panel within an accommodation chamber having a sealed structure. 
         [0006]    However, in such apparatus, since heat is difficult to release outside from the inside of the accommodation chamber having a sealed structure, temperature of the air in the chamber easily increases due to sunlight or due to heat generated from the panel during operation. Thus, temperature of the panel could be increased, which disables the image displaying on the panel. 
       SUMMARY OF THE INVENTION 
       [0007]    A first display apparatus according to the present invention comprises a display part, a housing which accommodates the display part, a circulator circulating the air in the housing around the display part in a vertical direction, and a fan provided on a rear side of the display part. The housing makes the display part be seen from outside therethrough. The fan converts the flow of the air circulating in the vertical direction to a horizontal direction in order to disperse heat generated from a rear surface of the display part. 
         [0008]    A second display apparatus according to the present invention comprises an accommodation chamber accommodating an image display panel. Here a circulation flow channel surrounding the image display panel is formed in the accommodation chamber. The circulation flow channel includes a rear side vertical flow channel portion extending in a vertical direction on a rear side of the image display panel and having a width smaller than that of the image display panel, a lateral side flow channel portion extending in the vertical direction on a lateral side of the image display panel, and a rear side horizontal flow channel portion extending in a horizontal direction on the rear side of the image display panel along a rear surface of the image display panel. The rear side horizontal flow channel portion allows communication between the rear side vertical flow channel portion and the lateral side flow channel portion. The accommodation chamber is further provided therein with a circulator circulating the air in the circulation flow channel, and a cooler cooling the circulating air. The circulator allows the air in the rear side vertical flow channel portion to flow into the lateral side flow channel portion through the rear side horizontal flow channel portion. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  is a perspective view of a display apparatus according to one embodiment of the present invention seen from a front side; 
           [0010]      FIG. 2  is a perspective view of an accommodation chamber included in the display apparatus seen from a rear side; 
           [0011]      FIG. 3  is a back view of the accommodation chamber; and 
           [0012]      FIG. 4  is a cross sectional view taken along an A-A line shown in  FIG. 3 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0013]    A display apparatus according to a preferred embodiment of the present invention is discussed in detail below with reference to drawings. 
         [0014]      FIG. 1  is a perspective view of the display apparatus seen from a front side. As shown in  FIG. 1 , the display apparatus comprises a housing  1 , a liquid crystal display panel  2  arranged in the housing  1 , a support base  3  with casters for supporting the housing  1 , and a cooling device  4 . The panel  2  includes a display surface viewable from outside the housing  1 . 
         [0015]    Inside the housing  1 , formed is an accommodation chamber where the panel  2  is accommodated. The chamber  5  has a structure in which an air inside is sealed. Therefore, the panel  2  in the chamber  5  does not contact outside air, and thus an outdoor installation of the display apparatus is enabled. That is, the panel  2  in the chamber  5  is protected from weather and dust, when the apparatus is installed outdoors. Also, the cooling device  4  comprises an evaporator, a condenser, and a compressor (not shown). The air in the chamber  5  is cooled by the cooling device  4 . 
         [0016]      FIG. 2  and  FIG. 3  are a perspective view and a plane view of the chamber  5  seen from a rear side, respectively. Also,  FIG. 4  is a cross sectional view taken along an A-A line shown in  FIG. 3 .  FIGS. 2 and 3  show the state of the chamber  5  when a rear wall thereof is taken off. 
         [0017]    As shown in  FIG. 4 , inside the chamber  5 , formed is a circulation flow channel  6  surrounding the panel  2 . As shown in  FIGS. 2 and 3 , the channel  6  includes a rear side vertical flow channel portion  61 , a plurality of rear side horizontal flow channel portions  62 , a pair of lateral side flow channel portions  63 ,  63 , and a lower side flow channel portion  64 . 
         [0018]    The portion  61  extends in a vertical direction on a rear side of the panel  2  at a position where it faces a central part of the panel  2 , and its width is smaller than that of the panel  2 . 
         [0019]    The pair of portions  63 ,  63  extends in a vertical direction on both lateral sides of the panel  2 , and is connected each other at a lower end part through the portion  64 . Here, the portion  64  extends in a horizontal direction on a lower side of the panel  2 . 
         [0020]    The portions  62  are arranged in the vertical direction. Each of the portions  62  contacts with a rear surface  22  of the panel  2 , and extends toward the portion  63  and is arranged in a space between the surface  22  and the portion  61 . Each of the portions  62  has a central part which communicates with the portion  61 , and both end parts which communicates with the portion  63 . 
         [0021]    Thus, the portion  61  and the pair of portions  63 ,  63  are communicated with each other through the portion  62 . 
         [0022]      FIG. 4  is a cross sectional view taken along an A-A line shown in  FIG. 3 . As shown in  FIG. 4 , a radiator plate  8  is formed inside the portion  62 . 
         [0023]    As shown in  FIG. 4 , the channel  6  further has a front side flow channel portion  65  extending in a vertical direction along a front surface  21  of the panel  2 . The portion  65  communicates with the portion  61  in its upper end part, and communicates with the portion  64  in its lower end part via the cooling device  4 . 
         [0024]    As shown in  FIGS. 2 to 4 , a pair of first fans  71 ,  71  and a plurality of second fans  72  for circulating the air in the channel  6  are further arranged in the chamber  5 . 
         [0025]    The fans  71 ,  71  are arranged near the upper end of the portion  65  and lead the air in the portion  65  to the portion  61 . On the other hand, the fans  72  are the fans for cooling a light source (such as LED) of the panel  2 . By arranging each of the fans  72  at the central part of the portion  62 , the fans  72  can be utilized as fans for leading the air in the portion  61  to the portion  62 . 
         [0026]    Therefore, by driving the fans  71  and  72 , the air in the channel  6  circulate in the portions  61 ,  62 ,  63 ,  64 , the device  4 , and the portion  65  as indicated by arrows shown in  FIGS. 3 and 4 . 
         [0027]    By flowing the air inside the portion  61 , the air in the chamber  5  can flow downward on the rear side of the panel  2  efficiently. 
         [0028]    Further, according to the fans  72 , since the air in the portion  61  can easily flow into the portions  62 , pressure loss in the channel  6  can be reduced. 
         [0029]    In the display apparatus described above, by circulating the air in the channel  6  by the fans  71  and the fans  72 , the air cooled by the cooling device  4  is led to the rear side of the panel  2  and flows along the rear surface  22 . Therefore, heat generated from the panel  2  is eliminated from the rear surface  22 . Although the air flowing along the rear surface  22  may be warmed by heat of the panel  2 , the warmed air is led to the portions  63 ,  63 , and the heat is diffused in a horizontal direction. 
         [0030]    Thus, although the air flowing along the rear surface  22  may be warmed by the panel  2 , the air in the rear surface  22  is kept cooler. Therefore, the panel  2  is cooled efficiently, and the temperature increase of the panel  2  is inhibited. Thus the functions of the panel  2  are maintained in good condition. 
         [0031]    Also, in the apparatus described above, since the heat generated from the panel  2  is eliminated. from the front surface  21  also, the panel  2  is cooled more efficiently. 
         [0032]    Further, in the apparatus described above, pressure loss in the channel  6  is reduced, and thus, has a high cooling efficiency. Also, in the apparatus described above, since the radiator plate  8  is formed in the portion  62 , the heat generated from the panel  2  is transmitted to the portion  62 , and thus, the display apparatus has a high cooling efficiency. 
         [0033]    The present invention is not limited to the foregoing embodiment in construction but can be modified variously by one skilled in the art without departing from the spirit of the invention as set forth in the appended claims. In the embodiment described above, the portion  65  communicates with the portion  61  in its upper end part and communicates with the cooling device  4  in its lower end. However, the present invention is not limited to this. For example, upper end parts of the pair of portions  63 ,  63  may be connected each other through an upper side flow channel portion provided on an upper side of the panel  2 , and the portion  61  may be communicated with the lower end part of the portion  65 , while the upper side flow channel portion may be communicated with the upper end part of the portion  65  via the cooling device  4 . 
         [0034]    Also, the constructions employed in the display apparatus described above can be applied not only to the display apparatus with the panel  2 , but also to various flat display apparatuses such as a plasma display, an organic EL (Electro-Luminescence) display. 
         [0035]    In the embodiment described above, the circulating means for circulating the air in the channel  6  may be formed only by the fans  71 , or said circulating means may be formed by both. the fans  71  and the fans  72 . 
         [0036]    When the circulating means is formed only by the fans  71 , the display apparatus may have a construction in which the heat led to the horizontal direction by the fan  72  is not collected by the cooling device  4 . For example, when the display apparatus is for indoor installation, since a sealed structure is not necessarily employed for the chamber  5 , the panel  2  can be cooled only by emitting the air led by the fans  72  from an air outlet provided on a lateral surface of the housing  1 . The air led by the fans  72  may be released outside through a duct, which is leading to the outside air, arranged on the lateral side of the chamber  5 , and extending in the vertical direction. 
         [0037]    On the other hand, when the display apparatus is for outdoor installation, since the sealed structure should be employed for the chamber  5 , it is preferable to collect the air led in the horizontal direction by the fans  72  by the cooling device  4 . 
         [0038]    When the circulating means is formed by both the fans  71  and the fans  72 , the display apparatus may have the structure where the fans  72  flow the air in the vertical direction and the horizontal direction, and the heat led to the horizontal direction is not collected by the cooling device  4 .