JP2011180182A - Electronic signboard - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic signboard capable of suppressing cooling unevenness of the display surface of a flat display. <P>SOLUTION: The electronic signboard 1 is constituted in such a manner that a flat display 10 is housed in a casing 8, which includes, in a position facing the display surface 11 of the flat display 10, a transparent plate 12 by forming a gap from the display surface 11.In the electronic signboard 1 whose display surface 11 is viewable from the outside through the transparent plate 12, cooling wind is blown through a gap 30A from one edge 11B of the display surface 11 to the other end 11A. A part of the cooling wind is branched from the one edge 11B to be supplied between the one edge 11B and the other edge 11A. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an electronic signboard that displays an advertisement on a flat panel display such as a liquid crystal display, and more particularly to a technique for uniformly cooling a display surface of the flat panel display.

  An electronic signboard (also referred to as “digital signage”) that includes a liquid crystal display and displays advertisement information such as images and characters on the liquid crystal display is known. In addition, in order to make it possible to use an electronic signboard outdoors on a street or the like, a liquid crystal display sealed in a casing and protected from wind and rain and dust is known. When the liquid crystal display is sealed in the casing in this way, heat is difficult to escape from the inside of the casing to the outside, and the liquid crystal display cannot be naturally air-cooled. Therefore, conventionally, an air cooling means for air-cooling the liquid crystal display is built in the casing, and the liquid crystal display is forcibly air-cooled (see, for example, Patent Document 1).

JP 2009-296105 A

However, with the recent increase in size and brightness of liquid crystal displays, the amount of heat generated by the liquid crystal display has increased, so the temperature of the liquid crystal display tends to increase, and this reduces the original function of the liquid crystal. A phenomenon (so-called blackout) that an image cannot be displayed on the display surface of the display occurs.
In particular, when an air passage is formed so that cooling air flows from one end to the other end of the display surface of the liquid crystal display, the air temperature rises due to the heat generated by the liquid crystal panel in the process of the cooling air going to the outlet. The temperature at the other end corresponding to the wind outlet becomes relatively high, and blackout occurs at the other end.
Such uneven cooling on the display surface becomes a problem not only in the liquid crystal display but also in other flat displays.
The present invention has been made in view of the above-described circumstances, and an object thereof is to provide an electronic signboard that can suppress uneven cooling of a display surface of a flat display.

  In order to achieve the above object, the present invention provides a flat panel display in a housing, and a transparent plate with a gap between the housing and the display surface at a position facing the display surface of the flat display. In the electronic signboard in which the display surface is visible from the outside through the transparent plate, cooling air is blown from the one end edge of the display surface to the other end edge of the display surface. A part is branched from the one end edge and supplied between the one end edge and the other end edge.

The said structure WHEREIN: You may supply the said cooling air branched from the said one end edge part from the both sides of the said display surface.
The said structure WHEREIN: The supply port which supplies the said cooling wind between the said one end edge part and the said other end edge part may be provided, and this supply port may be arrange | positioned diagonally toward the said other end edge part.
The said structure WHEREIN: The supply air path which supplies the said cooling wind between the said one end edge part and the said other end edge part may be formed, and this supply air path may be coat | covered with a heat insulating material.
In the above-described configuration, the vertically long flat display may be stood in the casing, and the cooling air may flow from the lower end edge to the upper end edge of the display surface.
The said structure WHEREIN: The supply port which supplies the said cooling wind between the said one end edge part and the said other end edge part is provided, and this supply port is made into 1/4 of the length of the said display surface from the said other end edge part. You may arrange | position in the position of.

  According to the present invention, cooling air is blown from the one end edge of the display surface to the other end edge of the display surface, and a part of the cooling air branches from the one end edge to the one end edge and the other end edge. Since the cooling capacity at the other end is enhanced and the temperature difference between the end and the other end is reduced, the unevenness of the display surface is suppressed and the entire display surface is improved. Can be cooled.

It is a perspective view which shows the external appearance structure of the electronic signboard which concerns on embodiment of this invention. It is a figure which abbreviate | omits and shows a part of longitudinal section of an electronic signboard. It is a cross-sectional view of a signboard body. It is a schematic diagram which shows a liquid crystal display, (A) is a longitudinal cross-sectional view which shows a liquid crystal display, (B) is a cross-sectional view which shows a liquid crystal display. It is a figure which shows the relationship between the distance from the upper end part of a liquid crystal display to a supply port, and the maximum temperature of the display surface of a liquid crystal display. It is a figure which shows the analysis result of the temperature of the display surface of a liquid crystal display, (A) is a figure which shows temperature distribution when not arrange | positioning a supply air path, (B) is temperature distribution when the supply air path is arrange | positioned. (C) is a figure which shows the parameter | index of the temperature in (A) and (B).

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a perspective view showing an external configuration of the electronic signboard 1. In addition, the directions such as up and down, left and right, and front and rear described below indicate directions when the electronic signboard 1 is installed and viewed from the front side.
The electronic signboard 1 includes a signboard body 2 that has a flat rectangular parallelepiped appearance, a base 4 that supports the signboard body 2, and a cooling unit 6 that cools the inside of the signboard body 2.

  The signboard body 2 has a vertically long, rectangular parallelepiped casing 8 having a height of about 2 meters and a width of about 1 meter, and a liquid crystal display 10 is placed inside the display surface 11 with the display surface 11 facing the front (front). It has been. The front surface of the housing 8 facing the display surface 11 has a large opening, and a transparent hard glass plate (transparent plate) 12 is fitted into the opening 9 so that the inside can be visually recognized. The entire surface 11 is configured to be visible. Various images and character information are displayed on the display surface 11 and used as a variable display type advertising medium. In addition, the signboard body 2 has a sealed structure such that a packing is disposed between the glass plate 12 and the housing 8, and has a structure that can withstand outdoor use such as on a street.

  The base 4 includes a frame frame 14 assembled in a rectangular frame shape and a pair of left and right support legs 16 that support the frame frame 14, and the signboard body 2 is fitted and fixed in the frame of the frame frame 14. The cooling unit 6 includes a unit case 18 in which a later-described refrigeration cycle 40 (FIG. 2) is incorporated, and is disposed on the lower end side of the signboard body 2. The inside of the signboard body 2, in particular, the liquid crystal display 10 is cooled by the cold air generated by the refrigeration cycle 40 of the cooling unit 6.

FIG. 2 is a view showing a vertical section of the electronic signboard 1 with a part thereof omitted, and FIG. 3 is a transverse sectional view of the signboard body 2.
As shown in FIGS. 2 and 3, a board mounting plate 20 is provided inside the housing 8 included in the signboard body 2, and is partitioned into a front side space 21 </ b> A and a back side space 21 </ b> B by the board mounting plate 20. The liquid crystal display 10 is arranged in the front space 21A. The circuit board mounting plate 20 is provided with various circuits on the surface facing the back space 21B. These circuits include, for example, a display control circuit that controls the display of the liquid crystal display 10, a storage circuit that acquires and holds advertisement information including images and still images displayed on the liquid crystal display 10 from the outside, and a cooling unit A cooling control circuit for driving 6 is included.

  The liquid crystal display 10 is a flat display and includes a display panel (liquid crystal panel) 22. The display panel 22 can have various shapes depending on the application. In the liquid crystal display 10 of this embodiment, the display panel 22 is a vertically long rectangle. The liquid crystal display 10 is fixed in a sealed space 28 formed in the front space 21 </ b> A of the housing 8 by providing a circulation channel 30 through which air circulates.

  As shown in FIG. 2, the circulation flow path 30 includes gaps 30 </ b> A to 30 </ b> D between the sealed space 28 and the liquid crystal display 10. That is, in the sealed space 28 of the front side space 21A, a gap 30A is formed between the display surface 11 of the display panel 22 and the glass plate 12, and a gap 30B is formed between the upper end portion 22A of the display panel 22. A gap 30 </ b> C is formed between the rear surface of the liquid crystal display 10 and a gap 30 </ b> D is formed between the lower end portion 22 </ b> B of the display panel 22. These gaps 30 </ b> A to 30 </ b> D are connected in an annular shape around the display panel 22 in this order, and surround the display panel 22. The glass plate 12 can be adjusted by a spacer 60 provided on the housing 8 so that the upper end of the glass plate 12 protrudes toward the front side.

  By forming such a circulation channel 30, the heat generated in the display surface 11 side portion of the display panel 22 passes through the circulation channel 30 and efficiently moves to the back side of the display panel 22. That is, when two sets of circulation fans 50 provided on the back side of the display panel 22 operate in the sealed space 28 of the housing 8, air is circulated as indicated by arrows in the drawing, and the display surface 11 side is circulated. Heat is transported to the back side. A refrigeration cycle 40 that recovers heat generated on the display surface 11 side is provided on the rear surface of the liquid crystal display 10.

The outline of the refrigeration cycle 40 includes an evaporator 42, a compressor 44, a condenser 46 and an expansion valve 48 disposed below the evaporator 42. Heat is recovered by the evaporator 42 and recovered. Heat is released by the condenser 46. That is, the evaporator 42 is installed in the gap 30 </ b> C on the back surface side at a position near the lower end portion 22 </ b> B of the display panel 22, and recovers heat from the air flowing through the circulation channel 30.
Further, the compressor 44, the condenser 46, and the expansion valve 48 are respectively disposed below the casing 8 and outside the sealed space 28. The condenser 46 faces, for example, a vent hole provided in the casing 8. The heat dissipating fan 51 is disposed adjacent to the condenser 46 to ventilate the heat through the condenser 46, and the heat collected by the evaporator 42 is blown by the heat dissipating fan 51. It discharges outside through the vent hole.

  According to this configuration, since the heavy refrigeration cycle 40 is disposed below the electronic signboard 1, the electronic signboard 1 has a low center of gravity, and the stability of the electronic signboard 1 is improved in outdoor use where the installation environment is unstable. To do. Further, since the evaporator 42 is disposed below the sealed space 28, the cooling efficiency in the sealed space 28 is good, and the heat generated in the display panel 22 is efficiently handled by the evaporator 42 in the process of circulating the air in the circulation channel 30. The recovered liquid is efficiently discharged from the condenser 46 through the vent hole provided in the housing 8, and the liquid crystal display 10 is thereby cooled. Also, the piping efficiency of the evaporator 42, the compressor 44, the condenser 46, and the expansion valve 48 is good. Instead of the refrigeration cycle 40, other heat exchange means capable of exchanging heat with the air flowing along the circulation flow path 30 may be employed.

  The circulation channel 30 is provided with a circulation fan (blower fan) 50 that circulates air in the circulation channel 30 to generate cooling air. The circulation fan 50 is disposed in each of the circulation channel 30 at a position near the upper end 22A of the display panel 22 and a position near the lower end 22B of the gap 30C on the back side of the liquid crystal display 10. The evaporator 42 is disposed downstream of the circulation fan 50 on the lower end 22B side. Although not shown, a plurality of circulation fans 50 are arranged in parallel in the cross section of the flow path (in the same horizontal plane) at each location. These circulation fans 50 are driven and controlled by a control circuit (not shown) provided on the board mounting plate 20.

  Each circulation fan 50 provided on the back side circulates cooling air in the direction of the solid arrow A along the circulation flow path 30. That is, when the circulation fan 50 is driven, the cooling air flows in the gap 30A on the display surface 11 side from the lower end inlet 30A-2 to the upper end outlet 30A-1 in the vertical direction. Then, the air flows from the outlet 30A-1 of the gap 30A through the gap 30B on the upper end 22A side of the display panel 22 to the gap 30C on the back surface side. The cooling air flowing into the gap 30C flows from the top to the bottom in the vertical direction, passes through the evaporator 42, passes through the gap 30D on the lower end 22B side of the display panel 22, and enters the gap 30A on the display surface 11 side. Return.

  In the refrigeration cycle 40, even when the heat generation Wa (unit W) of the liquid crystal display 10 and the heat generation Wb (unit W) due to solar radiation are generated, the temperature of the display panel 22 of the liquid crystal display 10 is set to a target temperature (unit ° C) or less. Designed for cooling capacity that can be maintained. This target temperature is set to a temperature (for example, 60 ° C.) that is lower by a predetermined temperature than a temperature (for example, 65 ° C.) at which a phenomenon that an image cannot be displayed on the display panel 22 (so-called blackout) can occur. The electronic signboard 1 also has a function of reducing the brightness of the display panel 22 when the solar radiation is strong and the cooling capacity is insufficient (when the temperature of the display panel 22 does not fall below the target temperature).

  According to these configurations, since the vertically long liquid crystal display 10 is stood in the casing 8 and the cooling air is flowed from the lower end portion 22B of the display surface 11 toward the upper end portion 22A, Hot air that tends to accumulate in the upper end portion 22A due to the influence of solar radiation or the like can be efficiently discharged from the display surface 11 side, and blackout at the upper end portion 22A of the display surface 11 can be prevented. Further, since the circulation fan 50 is arranged on the back side, the width of the gap 30A can be narrowed to increase the flow velocity of the cooling air passing through the gap 30A, so that the display surface 11 can be efficiently cooled. In addition, since the evaporator 42 is disposed downstream of the circulation fan 50, the evaporator 42 can efficiently recover the heat generated by the various electrical components on the display surface 11 and the back side.

  By the way, in the clearance 30A on the display surface 11 side of the circulation flow path 30, as described above, the cooling air flows from the bottom to the top, so that the cooling air warms in the process of passing through the display surface 11, and the clearance 30 A At the upper end 22A of the display panel 22 where the outlet 30A-1 (FIG. 2) is located, the temperature tends to be higher than that at the lower end 22B. In particular, depending on heat generated by solar radiation, only the upper end portion 22A of the display panel 22 may exceed the temperature at which blackout occurs. Therefore, if the cooling capacity of the refrigeration cycle 40 is further increased and measures are taken, the refrigeration cycle 40 is increased in cost and the size of the apparatus is increased. Moreover, if the brightness | luminance of the display panel 22 is reduced so that the temperature of 22 A of upper end parts of the display panel 22 may not exceed target temperature, the visibility under solar radiation will fall too much.

Therefore, in the present embodiment, in the gap 30A of the circulation channel 30, the surplus cooling capacity of the inlet 30A-2 (FIG. 2) of the gap 30A is distributed to the outlet 30A-1.
4 is a schematic view showing the liquid crystal display 10, FIG. 4A is a longitudinal sectional view showing the liquid crystal display 10, and FIG. 4B is a transverse sectional view showing the liquid crystal display 10. In FIG. 4A, the glass plate 12 is omitted.
The display panel 22 of the liquid crystal display 10 includes a bezel 23 for supporting the display panel 22 around the display surface 11. The bezel 23 includes an upper bezel 23A positioned at the upper end edge (other end edge) 11A of the display surface 11, a lower bezel 23B positioned at the lower end edge (one end edge) 11B of the display surface 11, and the display surface 11. Left and right side portions (both side portions) 11C, 11D and left and right bezels 23C, 23D.

In the display panel 22 of the present embodiment, two supply air passages 31, 32 that supply a part of the cooling air blown from the inlet 30A-2 of the gap 30A to the outlet 30A-1 side are provided on the left and right bezels 23C, 23D. The supply air passage 31 on the left side is arranged between the left side wall 8A of the housing 8, the glass plate 12, the left bezel 23C, and the partition plate 33 by arranging a partition plate 33 that partitions the display surface 11 and the left bezel 23C. It is formed. Further, the right supply air passage 32 is arranged between the right side wall 8B of the housing 8, the glass plate 12, the right bezel 23D, and the partition plate 34 by arranging a partition plate 34 that partitions the display surface 11 and the right bezel 23D. Formed.
The left and right side walls 8A and 8B, the glass plate 12, the left and right bezels 23C and 23D, and the partition plates 33 and 34 of the part forming the supply air passages 31 and 32 are covered with, for example, a heat insulating material 35 made of foamed polystyrene. It is comprised so that it can suppress that a wind warms in the process which flows through the supply air paths 31 and 32. FIG.

The partition plates 33 and 34 and the heat insulating material 35 covering these partition plates 33 and 34 constitute partition members 36 and 37, and these partition members 36 and 37 are relatively thin (for example, about 5 mm) and is fixed to the left and right bezels 23 </ b> C and 23 </ b> D at positions close to the display surface 11. Therefore, each of the partition plates 33 and 34 is preferably formed of a material (for example, iron or aluminum) having a strength that does not cause deformation by the cooling air even if the thickness is relatively thin.
As described above, the partition members 36 and 37 are formed relatively thin and are disposed on the left and right bezels 23C and 23D in the vicinity of the display surface 11, so that the supply air path is not hindered. The channel widths 31 and 32 can be made relatively large, and a relatively large amount of cooling air can be supplied to the outlet 30A-1 side.

One ends 36 </ b> A and 37 </ b> A of the partition members 36 and 37 are disposed on the lower end edge portion 11 </ b> B of the display surface 11. On the other hand, the other end 36B, 37B of each partition member 36, 37 is disposed at a position between the upper end edge 11A and the lower end edge 11B of the display surface 11, and the other end 36B, 37B is the supply air passage. The supply ports 31A and 32A of 31 and 32 are provided.
By providing the supply air passages 31 and 32 in this way, the cooling air blown into the gap 30A is branched into the cooling air flowing between the partition plates 33 and 34 and the cooling air flowing through the supply air passages 31 and 32, Cooling air that is not warmed by flowing through the supply air passages 31 and 32 is supplied between the lower edge 11B and the upper edge 11A. Further, since the cooling air flowing through the supply air passages 31 and 32 is supplied from both side portions 11C and 11D of the display surface 11, the entire width direction of the upper end edge portion 11A can be cooled.

  Each of the supply air passages 31 and 32 includes an inclined portion 38 in which a heat insulating material 35 extending along the left and right side walls 8A and 8B is inclined from the left and right side walls 8A and 8B to the display surface 11 side. 38, the supply ports 31 </ b> A and 32 </ b> A are arranged obliquely toward the upper edge 11 </ b> A of the display surface 11. Thereby, compared with the case where supply port 31A, 32A is provided so that it may orthogonally cross with respect to both sides 11C, 11D, the cooling air from supply air path 31, 32 and the cooling air which flows between partition plates 33, 34 are smooth. Since merging occurs and no stagnation or the like occurs in the merging portion, the display surface 11 in the vicinity of the outlet 30A-1 can be efficiently cooled.

  The temperature of the display surface 11 of the liquid crystal display 10 in the vicinity of the outlet 30A-1 varies depending on which position in the height direction of the display surface 11 the supply ports 31A and 32A are set. In the present embodiment, in the height direction of the display surface 11, the length L1 of the display surface 11 is 1549 mm, the length L2 of the display panel 22 is 1610 mm, and the lengths L3 of the upper and lower bezels 23A and 23B are respectively 30.5 mm. Hereinafter, the arrangement position of the supply ports 31 </ b> A and 32 </ b> A in the height direction of the display surface 11 will be described as a distance D from the upper edge 11 </ b> A of the display surface 11.

FIG. 5 is a diagram showing the relationship between the distance D from the upper edge 11 </ b> A of the display surface 11 to the supply ports 31 </ b> A and 31 </ b> B and the maximum temperature of the display surface 11 of the liquid crystal display 10.
When the distance D is 200 mm and 400 mm, the maximum temperature of the liquid crystal display 10 is lower than when the supply air passages 31 and 32 are not provided (distance D = 0 mm). In particular, when the distance D is 400 mm, the maximum temperature of the liquid crystal display 10 is about 2.9 ° C. lower than when the supply air passages 31 and 32 are not provided. The case where the distance D is 400 mm is a case where the supply ports 31A and 31B are arranged at a position of about 1/4 L1 from the upper end edge portion 11A of the display surface 11.

On the other hand, when the distance D is 600 mm, that is, when the supply ports 31A and 31B are close to the intermediate position between the upper edge 11A and the lower edge 11B of the liquid crystal display 10, the supply air passages 31 and 32 are not provided. The maximum temperature of the liquid crystal display 10 is higher than that.
Therefore, by providing the supply air passages 31 and 32 so that the arrangement positions of the supply ports 31A and 32A are about 1/4 L1 (distance D = 400 mm) from the upper end edge portion 11A of the display surface 11, the maximum of the liquid crystal display 10 can be provided. The temperature can be lowered satisfactorily.

FIG. 6 is a diagram illustrating the analysis result of the temperature of the display surface 11 of the liquid crystal display 10, and FIG. 6A is a diagram illustrating the temperature distribution when the supply air passage 31 is not disposed, and FIG. FIG. 6 is a view showing a temperature distribution when the supply air passage 31 is arranged, and FIG. 6C is a view showing a temperature index in FIGS. 6A and 6B. 6A and 6B show the results of analysis using the left half of the liquid crystal display 10 as a model.
As shown in FIG. 6 (A), when the supply air passage 31 is not arranged, the temperature is lowered from the temperature T0 of about 20 ° C. to the temperature T1 exceeding 50 ° C. from the lower edge 11B of the display surface 11 to the upper edge 11A. And gradually getting higher. The temperature T1 exceeding 50 ° C. occupies most of the upper range Q, which is about a quarter of the height direction of the display surface 11.

On the other hand, as shown in FIG. 6 (B), when the supply air passage 31 is arranged so that the position of the supply port 31A is 400 mm from the upper edge 11A of the display surface 11, it is shown in FIG. 6 (A). Compared to the case where the supply air passage 31 is not arranged, the temperature T0 is approximately the same at about 20 ° C. in the vicinity of the lower end edge portion 11B of the display surface 11; Is low. In particular, in the upper range Q of the display surface 11, the portion of the temperature T1 exceeding 50 ° C. is significantly reduced, and the portion of the temperature T2 to T6 below 50 ° C. occupies most. Therefore, the temperature difference between the lower edge 11B and the upper edge 11A is small.
Further, the temperature gradient from the lower end edge portion 11B to the upper end edge portion 11A was lower by about 2.4 ° C. than in the case where the supply air passage 31 shown in FIG.

  Therefore, by providing the supply air passages 31 and 32 so that the positions of the supply ports 31A and 32A are about 1/4 L1 (400 mm) from the upper end edge portion 11A of the display surface 11, the display surface 11 of the liquid crystal display 10 is provided. In addition to lowering the maximum temperature, the temperature difference between the lower end edge portion 11B and the upper end edge portion 11A is reduced to suppress uneven cooling on the display surface 11, and the display is made more than when the supply air passages 31 and 32 are not provided. The temperature of the surface 11 can be lowered overall.

  As described above, according to the present embodiment, the cooling air is blown from the lower end edge portion 11B of the display surface 11 toward the upper end edge portion 11A in the gap 30A, and a part of the cooling air flows at the lower end edge portion 11B. Branching from the bottom edge 11B and the bottom edge 11B. With this configuration, the cooling capacity of the lower edge 11B is distributed to the upper edge 11A, the temperature at the upper edge 11A is lowered, and the temperature difference between the lower edge 11B and the upper edge 11A can be reduced. As a result, uneven cooling due to cooling air on the display surface 11 can be satisfactorily suppressed.

  Moreover, according to this Embodiment, it was set as the structure which supplies the cooling air branched from the lower end edge part 11B from the both-sides parts 11C and 11D of the display surface 11. FIG. With this configuration, the entire width direction of the upper edge 11A is cooled as compared with the case where the cooling air branched from the lower edge 11B is arranged from one of the left side 11C or the right side 11D of the display surface 11. 11, the temperature difference between the lower edge 11B and the upper edge 11A can be reduced. As a result, uneven cooling due to cooling air on the display surface 11 can be satisfactorily suppressed.

  Further, according to the present embodiment, the supply ports 31A and 32A are arranged obliquely toward the upper edge portion 11A. With this configuration, compared with the case where the supply ports 31A and 32A are provided so as to be orthogonal to the side portions 11C and 11D, the cooling air from the supply air passages 31 and 32 is cooled with the cooling air flowing between the partition plates 33 and 34. Therefore, the display surfaces 11 can be efficiently cooled.

  Further, according to the present embodiment, the supply air passages 31 and 32 for supplying cooling air are formed between the upper end edge portion 11A and the lower end edge portion 11B, and the supply air passages 31 and 32 are formed by the heat insulating material 35. It was set as the structure covered. With this configuration, the cooling air can be prevented from warming in the course of flowing through the supply air passages 31 and 32, so that the temperature at the upper edge 11A is further lowered, and the temperature difference between the lower edge 11B and the upper edge 11A is reduced. Can be small. As a result, uneven cooling due to cooling air on the display surface 11 can be satisfactorily suppressed.

  Further, according to the present embodiment, the vertically long liquid crystal display 10 is stood in the casing 8 and the cooling air is made to flow from the lower end portion 22B of the display surface 11 toward the upper end portion 22A. With this configuration, hot air that tends to accumulate in the upper end portion 22A due to the influence of solar radiation during outdoor installation can be efficiently discharged from the display surface 11 side, and blackout at the upper end portion 22A of the display surface 11 can be prevented. Can do.

  Further, according to the present embodiment, the supply ports 31A and 32A for supplying cooling air are provided between the upper end edge portion 11A and the lower end edge portion 11B, and the supply ports 31A and 32A are connected to the display surface from the upper end edge portion 11A. It was set as the structure arrange | positioned in the position of 1/4 of 11 length L1. With this configuration, the maximum temperature of the display surface 11 of the liquid crystal display 10 can be satisfactorily lowered as compared with the case where the supply air passages 31 and 32 are not arranged. Thereby, blackout at the upper edge portion 11A can be reliably prevented.

However, the above embodiment is an aspect of the present invention, and it is needless to say that the embodiment can be appropriately changed without departing from the gist of the present invention.
For example, in the above embodiment, the supply air passages 31 and 32 are provided on both the left and right bezels 23C and 23D. However, for example, when the width of the display surface 11 is narrow, one of the left and right bezels 23C and 23D is provided. May be provided.
In the above embodiment, the one end 36A, 37A of each partition member 36, 37 is arranged at the lower end edge 11B of the display surface 11, and the cooling air is branched from the lower end edge 11B of the display surface 11. However, the present invention is not limited to this. For example, it may be disposed on the lower bezel 23B, or may be positioned below the lower end 22B of the display panel 22.

In the above embodiment, the supply air passages 31 and 32 are provided on the left and right bezels 23C and 23D of the display panel 22. However, when the left and right bezels 23C and 23D are formed narrow, the outside of the display panel 22 is provided. May be provided.
The supply air passages 31 and 32 are formed by providing the partition plates 33 and 34, but may be formed by ducts. In this case, the duct is covered with a heat insulating material, and ducts extending between the upper edge 11A and the lower edge 11B from the inlet 30A-2 of the gap 30A are arranged on the left and right bezels 23C and 23D, respectively. That's fine.

Moreover, in the said embodiment, although it was set as the structure which flows cooling air from the lower end edge part 11B of the display surface 11 of the liquid crystal display 10 to the upper end edge part 11A, if it is the structure which flows in one direction, cooling air will be arbitrary direction. May be used. In this case, supply ports 31A and 32A may be disposed on the downstream side of the cooling air.
In the above embodiment, the liquid crystal display 10 is arranged in the sealed space 28 and the cooling air is circulated around the liquid crystal display 10. However, the present invention is not limited to this, and the outlet 30 </ b> A- 1 of the gap 30 </ b> A on the display surface 11 side. The cooling air generated from the air may be discharged to the outside.

Moreover, in the said embodiment, although the glass plate 12 was illustrated as a transparent plate arrange | positioned facing the display surface 11, if it is a board | plate material transparent to the extent which an inside can be visually recognized, board | plate materials of arbitrary materials can be used.
Moreover, in the said embodiment, although the liquid crystal display 10 was illustrated to the flat type display, this invention is another flat type display (for example, an organic electroluminescent display, a plasma display, etc.) where it is preferable to cool the display surface 11 uniformly. It can also be applied to an electronic signboard equipped with a).

1 Electronic signboard 8 Case 10 Liquid crystal display (flat display)
11 Display surface 11A Upper end edge (other end edge)
11B Lower edge (one edge)
11C Left side (both sides)
11D Right side (both sides)
12 Glass plate (transparent plate)
30A Clearance 31, 32 Supply air passage 31A, 32A Supply port 35 Insulating material

Claims (6)

A flat display is placed in a housing, a transparent plate is provided in the housing at a position facing the display surface of the flat display with a gap between the display surface, and the display surface is placed outside through the transparent plate. In the electronic signage made visible from
Cooling air is blown from the one end edge portion of the display surface to the other end edge portion in the gap, and a part of the cooling air branches from the one end edge portion and the one end edge portion and the other end edge portion. An electronic signboard that is supplied between   The electronic signboard according to claim 1, wherein the cooling air branched from the edge of the one end is supplied from both sides of the display surface.   2. A supply port for supplying the cooling air is provided between the one end edge and the other end edge, and the supply port is disposed obliquely toward the other end edge. Electronic signboard according to 2.   4. A supply air passage for supplying the cooling air is formed between the one end edge portion and the other end edge portion, and the supply air passage is covered with a heat insulating material. Electronic signboard as described in.   5. The vertically long flat display is housed in a state of standing in the casing, and the cooling air is flowed from the lower end edge to the upper end edge of the display surface. Electronic signboard as described in.   A supply port for supplying the cooling air is provided between the one end edge portion and the other end edge portion, and the supply port is disposed at a position of a quarter of the length of the display surface from the other end edge portion. The electronic signboard according to any one of claims 1 to 5, wherein the electronic signboard is provided.

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