JP5028035B2 - Image display device - Google Patents

Description

  The present invention relates to an image display device that displays television images and the like, and more particularly to a heat dissipation structure thereof.

  2. Description of the Related Art In recent years, image display devices that display television images and the like have become thinner, and image display devices using so-called flat display panels such as plasma display panels and liquid crystal panels have become mainstream in place of conventional CRTs.

  FIG. 1 is a perspective view from the image display surface side of a plasma display which is an example of such a flat image display device. As shown in the figure, a plasma display 1 is configured by covering a panel 2 which is a plasma display panel (PDP), a circuit board for driving the panel 2 and displaying an image with a front cover 3 and a back cover 4. Has been.

  FIG. 10 is a schematic cross-sectional view showing the internal configuration of the conventional plasma display 1. As shown in the figure, inside the front cover 3 and the back cover 4 of the plasma display 1 are a panel 2 for displaying an image, a chassis 5 for supporting the panel 2 on the front side, and a panel fixed to the back side of the chassis 5. A plurality of circuit boards 6 for driving 2 are housed.

  Here, from the operating principle of displaying an image using gas discharge in the glass panel, the panel 2 of the plasma display tends to be hot, but when the panel 2 becomes hot, the electrodes formed inside the panel 2 Defects such as a change in electric capacity and the failure of normal discharge occur. Therefore, for the purpose of keeping the panel 2 at a predetermined temperature (as an example, 70 to 80 ° C.) or lower, a resin sheet 7 having high thermal conductivity is provided between the chassis 5 and the panel 2 as shown in the figure. The heat of the panel 2 is effectively transmitted to the chassis 5 by sandwiching, and the effect of heat radiation and the effect of temperature equalization are obtained at the same time.

  Further, vent holes 18 and 19 are provided in the upper and lower portions of the back cover 4 to generate an air flow as indicated by an arrow 10 in the figure between the space 20 inside the back cover 4 and the outside, thereby The chassis 5 and the circuit board 6 in the cover 4 are cooled by natural convection of the outside air. Note that the vent holes 18 and 19 are actually a collection of minute openings as shown in FIG. 11, but in FIG. 10, only their positions are roughly shown.

  FIG. 11 is a view of the back cover 4 of the conventional plasma display 1 as seen from the back side. The upper vent hole 18 and the lower vent hole 19 are both circular holes having a diameter of 3 to 5 mm with a center interval of 6 mm. The back cover 4 is arranged over almost the entire region in the left-right direction, arranged in 5 rows at a pitch of ˜8 mm. Moreover, as an opening rate represented as a ratio of the total area of the opening with respect to the whole part in which the vent hole is formed, it is about 30 to 60%.

In the following description of the present invention, the up and down direction refers to the up and down direction when the image display device is placed in a normal use state (ie, the vertical direction), and the left and right direction refers to a direction orthogonal to this (ie, horizontal Direction). Usually, the panel 2 is held in a horizontally long state to perform image display. Therefore, the up and down direction corresponds to the short side direction of the panel 2, and the left and right direction corresponds to the long side direction of the panel 2.
Japanese Patent Laid-Open No. 10-240138

  As described above, in an image display device, particularly a plasma display, it is important to keep the panel 2 in an operating state below a certain temperature. It is assumed that the number of electrodes in the vertical direction and the horizontal direction in 2 needs to be increased, and the amount of heat generated in the panel 2 is further increased, such as an increase in discharge locations.

  Then, the heat transferred from the panel 2 through the chassis 5 to the air flowing from the lower vent hole 19 of the back cover 4 further increases, and the air reaches the vent hole 18 at the upper portion of the back cover 4 more. It absorbs a lot of heat and gets hot. If it becomes like this, sufficient cooling will become impossible as it approaches the upper ventilation hole 18, and it will become difficult to keep the panel 2 below predetermined temperature.

  Even if it is not as prominent as a plasma display, the problem of countermeasures against the temperature rise inside the back cover caused by the high quality of the display image is the display panel itself, the built-in light source, and driving these. This is common in liquid crystal display panels, so-called cold cathode display panels, EL display panels, and the like as the temperature of circuit boards and the like increases.

  In view of the above-described problems, the present invention provides an image display device that can sufficiently suppress natural temperature convection from a vent hole provided in a back cover, due to a high image quality of a panel. With the goal.

In order to solve the above problems, an image display device of the present invention includes a panel for displaying an image, a chassis that supports the panel on the front surface, and a plurality of circuits that are fixed to the rear surface of the chassis with a predetermined gap therebetween. An image display device comprising a board, and a front cover and a back cover for accommodating them, wherein the chassis and the back cover are arranged at positions where the circuit board is not disposed between the chassis and the back cover. A partition plate is provided to divide the space inside the back cover into a plurality of regions in the vertical direction, and the back cover corresponds to the region divided by the partition plate. It has the several ventilation hole provided so that it may do.

  According to the present invention described above, the air path inside the back cover is shortened and the temperature rise of the air is suppressed, so that the effect of suppressing the temperature rise due to natural convection through the vent hole can be sufficiently obtained, and the display image It is possible to obtain an image display device that avoids the adverse effects of temperature rise associated with higher image quality.

  In the image display device described above, it is preferable that the partition plate divides the space inside the back cover into two vertically. In addition, a plurality of the vent holes are provided in the upper and lower portions of the region, and further, the vent hole provided in the lower portion of the same region as the vent hole provided in the upper portion of the region. Are preferably positioned so that at least a part thereof overlaps in the left-right direction. By doing in this way, the air path can be shortened by the partition plate, and the effect of cooling the inside of the back cover can be effectively exhibited.

  Further, the vent hole provided in the lower portion of the region and the vent hole provided in the upper portion of the other region located below the region are in a position where they do not overlap in the left-right direction, or The vent hole provided on the lowermost side of the region is at the same height or lower than the vent hole provided on the uppermost side of the other region located below the region. It is preferable to be located at. In this way, air whose temperature has risen due to passing through the lower area of the image display device does not flow again into the upper area, so that the cooling effect inside the back cover by the outside air is effective. Can get to.

  The chassis and the circuit board are cooled by natural convection of outside air through the vent hole without using a fan, the panel is a plasma display panel, the panel and the chassis, A resin sheet is preferably provided between the two.

  Furthermore, the cross-sectional shape of the partition plate is a trapezoidal shape in which the chassis member side is wide and the back cover side is narrow, the partition plate is formed integrally with the chassis, or the partition plate However, it is preferably formed integrally with the back cover.

  Hereinafter, an image display apparatus of the present invention will be described with reference to the drawings.

(Embodiment 1)
The image display apparatus according to the first embodiment of the present invention will be described using a plasma display example as in the conventional example. First, the external appearance seen from the image display surface side is the same as the conventional one as shown in FIG. 1, and the plasma display 1 has a configuration in which a panel 2 as an image display panel is covered with a front cover 3 and a back cover 4. Has been. Further, the internal structure of the plasma display 1 is as shown in a schematic sectional view in FIG. 2, and the basic configuration is the same as the conventional one shown in FIG.

  Although not shown in detail in FIG. 2, the panel 2 is configured by bonding front and back glass substrates having transparent electrodes, and neon gas or xenon gas is inserted into a minute gap between the two glass substrates. A discharge gas such as is enclosed. A voltage is applied to the electrode to cause discharge, and the discharge gas is turned into a plasma to generate ultraviolet light. This ultraviolet light stimulates the red, blue, and green phosphors applied to the back glass substrate to display an image. Let For example, electrodes are arranged in the horizontal direction on the front glass and in the vertical direction on the rear glass, so that light emission at the intersection can be controlled. One glass substrate has a thickness of about 1.5 to 3 mm. In order to display an image with such a mechanism, the panel 2 repeatedly discharges over the entire surface and itself tends to become high temperature. While the power consumption of the entire set in the plasma display 1 is 300 to 450 W, the power consumption of the panel 2 is about 200 to 300 W, accounting for about two-thirds of the whole. It is an important issue to keep the temperature at a predetermined temperature of 70-80 ° C.

  The front cover 3 and the back cover 4 are configured to cover the chassis 5 to which the panel 2 and the circuit board 6 are attached, and are made of steel having a thickness of 0.5 to 2 mm. Among these, the front cover 3 also serves as an escutcheon frame that covers the periphery of the image display surface of the panel 2. As will be described in detail later with reference to FIG. 3, one back cover 4 has a vent hole for taking in and discharging outside air in order to suppress the temperature rise of the panel 2 by cooling the chassis in the back cover 4. 13, 14, 15, and 16 are provided.

  A space between the panel 2 and the chassis 5 that supports the panel 2 is filled with a resin sheet 7 having high thermal conductivity. The area of the resin sheet 7 viewed from the front is substantially equal to the panel 2 and is rectangular, and the thickness is about 1 to 2 mm. By interposing the resin sheet 7 therebetween, the panel 2 basically composed of a glass substrate and the chassis 5 which is a metal are brought into close contact with each other, and the heat conduction effect from the panel 2 to the chassis 5 is enhanced. For this reason, as the material of the resin sheet 7, silicon or the like having both flexibility and thermal conductivity is used.

  The chassis 5 is substantially the same shape and area as the panel 2 as viewed from the front, and is made of metal having a thickness of about 1.5 to 3 mm. The role of holding the panel 2 within the front cover 3 and the back cover 4 to support the whole and the heat conducted from the panel 2 via the resin sheet 7 are diffused in the in-plane direction of the chassis 5 itself. It plays the role of heat so as to dissipate heat to the spaces 11 and 12 between the chassis 5 and the back cover 4. For this reason, as the material of the chassis 5, aluminum having a good thermal conductivity is used, and a heat radiating fin may be formed on the back surface portion on the back cover 4 side as necessary. Further, the chassis 5 may be provided with ribs in the vertical direction and the horizontal direction for reinforcement.

  On the back side of the chassis 5, there are a plurality of circuit boards 6 constituting a power supply unit and a tuner unit for displaying an image, and a signal processing circuit and a drive circuit for applying a signal to the electrodes of the panel 2 to display an image. Are fixed to the boss of the chassis 5 so as to be parallel to the panel 2.

  The plasma display 1 according to the present embodiment is different from the conventional plasma display 1 shown in FIG. 10 in that a partition plate 8 is provided that divides the space in the back cover 4 in the vertical direction to form a plurality of regions. The back cover 4 has ventilation holes 13, 14, 15, and 16 for taking in and discharging outside air correspondingly to the upper area 11 and the lower area 12 divided by the partition plate 8. It is a point provided.

  The partition plate 8 is made of resin, and as shown in FIG. 3 which is a state of the back cover 4 viewed from the back, in the present embodiment, the partition plate 8 is formed in the entire center in the vertical direction of the panel 2 over the entire horizontal direction. ing. That is, the space inside the back cover 4 is vertically divided into two regions, an upper region 11 and a lower region 12, which are substantially the same size. In the present embodiment, the partition plate 8 is screwed using a screw hole provided in the chassis 5. However, even if the partition plate 8 is formed integrally with the chassis 5, it is also integrated with the back cover 4. It may be formed. However, in any case, the gap between the chassis 5 and the back cover 4 is tightly closed in the height direction of the partition plate 8, that is, in the thickness direction of the plasma display 1. That is, it is preferable that substantial air movement is blocked between the two regions 11 and 12 divided by the partition plate 8.

  Further, as shown in FIG. 2, the partition plate 8 has a trapezoidal shape in which the chassis 5 side is wide and the back cover 4 side is narrow, and the width is 40 mm on the chassis 5 side and 20 mm on the back cover 4 side. . In addition, the height of the partition plate 8 of the present embodiment, that is, the distance between the chassis 5 and the back cover 4 is 60 mm. By making the cross section trapezoidal in this way, the air flow 10 in the vicinity of the partition plate 8 is controlled so that natural convection is more likely to occur. That is, as shown in FIG. 2, the opening 14 provided in the lower portion of the upper region 11 makes it easier for outside air to enter the upper region 11, and conversely, the opening provided in the upper portion of the lower region 12. In the vicinity of the portion 15, the air inside the lower region 12 tends to come out to the outside of the back cover 4. However, the cross-sectional shape of the partition plate 8 is not limited to such a trapezoidal shape, and may be a triangle, a semicircle, a rectangle, or a square. In order to make the air flow near the partition plate 8 smoother as described above, the width of the back cover 4 side is made smaller than the width of the partition plate 8 on the chassis 5 side, or at least the same. It is preferable to use a width. Therefore, when the partition plate 8 is formed integrally with the back cover 4, it is difficult to reduce the width on the back cover 4 side due to processing restrictions, so the cross-sectional shape of the partition plate 8 should be rectangular. Is preferred. Further, regarding the cross-sectional width direction of the partition plate 8, that is, the thickness in the vertical direction, considering the strength of the partition plate 8 itself, the effect of blocking the temperature of the air between adjacent regions across the partition plate 8, and the like. On average, about 30 mm is considered appropriate. However, the present invention is not limited to this.

  In the present embodiment, the material of the partition plate 8 is easily processed, adheres to the chassis 5 and the back cover 4, and exchanges heat between the upper region 11 and the lower region 12. Considering the difficulty, it is made of resin. However, it may be made of metal, including the case where it is formed integrally with the metal chassis 5 and the back cover 4. In particular, when the partition plate 8 is made of metal, for example, aluminum having high thermal conductivity, the thermal conductivity between the partition plate 8 and the chassis 5 or the back cover 4 is increased. It can be expected that the heat of the air accumulated in the upper portion of the region 12 formed on the side is released to the other through the partition plate 8. Further, the heat of the panel 2 can be transferred from the chassis 5 to the back cover 4 through the partition plate 8 and directly escaped to the outside.

  As shown in FIGS. 2 and 3, the back cover 4 has a plurality of ventilation holes in the upper and lower portions of each region 11 and 12 divided vertically by the partition plate 8. Yes. Specifically, the ventilation hole 13 provided at the upper part of the upper region 11, the ventilation hole 14 provided at the lower part, the ventilation hole 15 provided at the upper part of the lower region 12, and the ventilation hole 16 provided at the lower part. is there. In this way, by forming vent holes in the upper and lower parts of each of the two regions where the movement of the mutual air is substantially blocked by the partition plate, as shown by arrows 10 in the figure, An air flow is generated by natural convection in the area, and the cooling effect on the chassis 5 and the circuit board 6 in each area is exhibited. In FIG. 2, which is a schematic cross-sectional view, only the position of the vent hole is shown as in FIG. 10 showing the conventional example.

  As is apparent from FIG. 3, the arrangement of the air holes at each location is substantially the same as that of the conventional plasma display 1 shown in FIG. The vent hole 13 formed in the upper part of the upper region 11, the vent hole 14 formed in the lower part, the vent hole 15 formed in the upper part of the lower region 12, and the vent hole 16 formed in the lower part are respectively The back cover 4 is formed substantially symmetrically about the center in the left-right direction, and is formed over substantially the entire left-right direction. In addition, the shape and interval of each of the air holes 13 to 16 are the same as the air holes 18 and 19 of the conventional plasma display 1, and in this embodiment, circular holes with a diameter of 4.5 mm are formed at intervals of 6.5 mm. They are arranged in 5 rows and the aperture ratio is 40%.

  The shape of the vent hole is not limited to a circle, and may be other shapes such as an ellipse, an oval, a quadrangle, and the like. Of course, a larger opening ratio of the air holes is desirable from the viewpoint of heat dissipation, but should be appropriately determined from the problem of the strength of the back cover 4 and the safety of the set as the plasma display 1. Is.

  Next, the effect in this embodiment is demonstrated.

  As described above, in the plasma display 1 of this embodiment, the space in the back cover 4 is divided into the upper region 11 and the lower region 12 by the partition plate 8. And the vent holes 13, 14, 15, and 16 are provided in the back cover 4 of the position corresponding to the upper part and the lower part of each area | region. Therefore, as indicated by an arrow 10 in FIGS. 2 and 3, in the upper region 11, air entering from the lower vent hole 14 is discharged from the upper vent hole 13, and in the lower region 12, the lower vent hole is exhausted. An air flow in which air entering from 16 is discharged from the upper vent 15 is generated as natural convection. For this reason, the temperature of the space inside the back cover 4 can be lowered for each region.

  That is, in the plasma display 1 of the present embodiment, the path from the air flowing into the space inside the back cover 4 until it flows out is shortened, so that the temperature of the panel 2 is transmitted to the chassis 5 and the circuit board 6. The contact time with a heating element such as an IC mounted on the IC is shortened, and the temperature rise of the air itself is not increased so much that it is discharged to the outside. Further, since the space inside the back cover 4 is partitioned in the vertical direction, only the uppermost part of the space inside the back cover 4 is not particularly heated, and the chassis 5 is effectively cooled, so that the panel 2 The entire temperature can be made lower than a predetermined temperature.

  On the other hand, in the conventional plasma display 1 shown in FIG. 10 and FIG. 11, the space 20 inside the back cover 4 is one large area, so that the air flowing in from the lower vent hole 19 The path to flow out of the vent hole 18 is long. As a result, it takes a long time for the air that has entered the interior of the back cover 4 to come into contact with a heating element such as an IC mounted on the chassis 5 or a plurality of circuit boards 6 that has been heated by the heat of the panel 2. Become. For this reason, the temperature of the air in the interior space of the back cover 4 rises, and the temperature of the upper portion of the space 20 inside the back cover 4 becomes particularly high. As a result, the temperature of the panel 2 can be lowered sufficiently. Probably not.

  In FIG. 3, the arrangement of the vent holes 13 to 16 in the back cover 4 is shown as being symmetrically formed around the central portion of the back cover 4 in the left-right direction. In order to obtain a uniform and effective cooling effect by applying outside air to as large an area as possible with respect to the chassis 5, it is preferable to make the lateral length of the vent hole as large as possible and to make it symmetrical. Needless to say, in the actual plasma display panel 1, the back cover 4 must be provided with a video signal input / output terminal portion, etc., and the position of the vent hole is determined in consideration of only the heat radiation effect. There are many cases where this is not possible. FIG. 4 shows the arrangement pattern of the vent holes in such a case.

  In FIG. 4, the upper vent hole 13 and the lower vent hole 14 of the upper region 11 are formed at the same position in the upper and lower directions although they are slightly leftward in the left-right direction. Compared with the vent hole 15, the lower vent hole 16 is formed in a state shifted to the right side, and the width in the left-right direction is also narrowed. As described above, in one region (here, the lower region 12), the upper and lower vent holes have different positions and widths in the left and right direction, the number of vent holes and the aperture ratio due to various restrictions. Even if they cannot be formed in the same way, the panel temperature reduction effect according to the present invention can be obtained by natural convection through the air holes if at least a part of them is provided in the left-right direction. It is done. In other words, as described above, if each of the regions divided by the partition plate 8 is provided with the upper and lower ventilation holes at positions where a part thereof overlaps in the left-right direction, The air path in the part is reliably shortened by the partition plate 8. For this reason, the temperature distribution within the back cover 4 such as the position and shape of the heat radiating fins provided on the chassis 5 and the heat generation state of the circuit board attached to the rear surface of the chassis are also taken into consideration, and the panel is more efficiently It can be seen that the arrangement pattern of the air holes that can lower the temperature may be determined.

(Embodiment 2)
FIG. 5 shows the back cover 4 of the second embodiment of the plasma display 1 according to the present invention as seen from the back side.

  Here, the partition plate 8 provided in the central portion of the back cover 4 in the vertical direction divides the space inside the back cover 4 into two regions, and a plurality of regions above and below each region. This is the same as the first embodiment in that individual ventilation holes are provided. The feature of this embodiment is that the lower ventilation hole 14 in the upper region (corresponding to the region 11 in FIG. 2 although a sectional view is not shown) and the lower region (similarly, lower than that region) The upper ventilation hole 15 corresponding to the region 12 in FIG. 2 is provided at a position that does not overlap in the left-right direction. Specifically, as shown in FIG. 5, the air holes 13 and 14 provided in the upper region are both divided into three portions formed at predetermined intervals in the lateral direction, In the region, the vent holes 15 and 16 corresponding to the upper part and the lower part are provided only at two places in the interval portion where the vent hole is not provided in the upper region.

  By doing so, the air flow is as shown by the arrow 10 in the figure, and in the lower region, once enters from the lower vent hole 16 and is discharged from the upper vent hole 15 in a state where the temperature is increased. It is possible to prevent the air from entering the upper region from the lower vent 14 of the upper region. For this reason, the temperature of the outside air entering the upper region is always at or close to the environmental temperature (so-called room temperature), and the space inside the back cover 4 in the upper region can be effectively cooled.

  In addition, in FIG. 5 which shows the vent hole formation pattern of this Embodiment, in the upper side area | region and the lower side area | region, about the vent hole formation position and arrangement | positioning of the left-right direction about the vent holes 13 and 14 and the vent holes 15 and 16, respectively. The pattern is the same, and the upper area is divided into three and the lower area is divided into two. However, from the viewpoint of entering the back cover 4 in the lower region and preventing the temperature-increased air from entering the upper region again as shown in this embodiment, the shape is not limited to this shape. . In short, if the vent hole provided in the lower part of a certain area and the vent hole provided in the upper part of the other area located below that area are provided in positions that do not overlap in the left-right direction Good. Specifically, in FIG. 5, the upper vent hole 13 in the upper region and the lower vent hole 16 in the lower region are formed over almost all of the back cover 4 in the left-right direction, thereby allowing more outside air to enter and exit. It is also possible to facilitate natural convection in each area as an easy to be performed.

  Here, in order to confirm the effect of the present invention described above, the results of numerical analysis of the panel 2 temperature of the plasma display 1 according to the present embodiment are shown in FIGS.

  FIG. 6 is a temperature contour diagram showing the panel surface temperature distribution of the structure according to this embodiment. Note that the shape and arrangement of the ventilation holes of the partition plate 8 and the back cover 4 are as shown in FIG. That is, the inner space of the back cover 4 is divided into two vertically by a partition plate 8 provided in the center in the vertical direction of the panel, and no air movement occurs between the two divided areas. The ventilation holes are as shown in FIG. 5, and upper and lower ventilation holes 13 and 14 in the upper region and upper and lower ventilation holes 15 and 16 in the lower region are arranged in the lateral direction of the panel 2. Avoid overlapping positions. As other analysis conditions, assuming that an actual plasma display 1 having a panel size of 42 inches is assumed, the panel size is 920 mm wide and 520 mm high, and the circuit board 6 attached to the rear surface of the chassis 5 is shown in FIG. The arrangement was as shown in FIG. Reference numerals 21 to 24 in FIG. 8 denote substrates on which panel drive circuits are mounted. The power consumption (heat generation amount) of each substrate is 20 W for both 21 and 22, and 3 W for each one is 23 W. Was 10 W. In addition, since 25 is a substrate on which a power supply circuit for driving the panel is mounted, the power consumption is set to 50 W. The heating value of the panel itself was 200 W, and there was no difference in the heating value of each part of the panel.

  On the other hand, FIG. 7 is a temperature contour diagram of the surface of the panel 2 of the conventional plasma display 1, and the space 20 inside the back cover remains as one region without providing a partition plate, and is provided in the back cover 4. The arrangement of the vents is the same as that shown in FIG. 11, that is, the vent hole 18 provided in the upper part and the vent hole 19 provided in the lower part. About the calorific value of the panel 2 and the circuit board 6, the shape and arrangement of the circuit board 6, the shape / material / thickness of the chassis 5, the material of the resin sheet 7, etc., all of the panel according to this embodiment shown in FIG. The conditions for temperature calculation were exactly the same. For the numerical analysis, the finite volume method was used, and the analysis region was divided into about 3 million elements for calculation.

  6 and 7, when comparing the area of the portion where the panel surface temperature is 75 ° C. or higher, FIG. 6 showing the panel 2 according to the present embodiment is less than half of the entire panel area. It can be seen that the temperature of the panel 2 can be clearly reduced as compared with FIG. Further, the highest temperature in the calculation is 80.4 ° C. for the panel according to this embodiment of FIG. 6 and 82.8 ° C. for the conventional panel of FIG. The maximum temperature of the panel is 2.4 ° C lower.

  Further, looking at the trend of the temperature distribution of the panel, in FIG. 7 showing the conventional example, a high value of 80 ° C. or higher is obtained in a considerably wide area from the vicinity of the substrate 25 on which the power circuit for driving the panel is mounted to the upper part of the panel. Show. On the other hand, in the case of the present embodiment shown in FIG. 6, the vicinity of the substrate 25 on which the power supply circuit is mounted is the maximum temperature, and this portion exceeds 80 ° C., but the range is very narrow. In other words, in the conventional example, since the path through which the air entering from the vent hole is discharged is long, the temperature of the air inside the back cover becomes high, and the heat of the chassis hardly diffuses inside the back cover, so that the panel temperature is lowered. On the other hand, in this embodiment, in each of the upper and lower regions divided into two by the partition plate 8, the temperature rise of the air is suppressed by the amount of the shortened path, via the chassis. It is thought that the heat release from the panel was sufficiently performed.

  From the above results, by dividing the space inside the back cover 4 and shortening the path of the air passing through the inside space, in other words, by making the air cooling effect by natural convection independent in each region, the panel 2 It can be seen that the temperature rise is effectively suppressed. Moreover, even if it sees by the average value of the temperature in all the analysis points, in the case of the panel which concerns on this embodiment shown in FIG. 6, it will be 72.8 degreeC in the case of the conventional panel of FIG. It can be seen that the overall panel temperature can be reduced.

  Note that the panel surface temperature contour diagram shown in FIGS. 6 and 7 is a diagram showing the surface temperature distribution of the panel, and is a diagram viewed from the front side of the panel where the display image is originally observed. However, in order to confirm the effect of the present invention that the panel temperature is reduced by the structure on the back side of the chassis 5, and the consistency with FIGS. 5, 8, and 11 showing the structure on the back side. Therefore, here, the analysis results are shown reversed right and left so as to be a view as seen from the back side of the panel.

(Embodiment 3)
FIG. 9 is a view showing the back cover 4 according to the third embodiment of the plasma display 1 according to the present invention.

  In the third embodiment, the partition plate 8 that divides the region of the back cover 4 into upper and lower portions is arranged so as to form one step at the left and right intermediate portions of the panel 2 unlike the previous embodiments. There is a feature in that. That is, as shown in FIG. 9, the partition plate 8 is formed so as to be on the upper side in the left side portion and on the lower side in the right side portion from the left and right intermediate portion of the panel 2. Of course, a partition plate 8 having a cross-sectional shape similar to the other is also provided in the central vertical direction portion connecting these left and right step portions, and the space inside the back cover 4 is an upper region (not shown, but in the region 11 of FIG. 2). And the lower region (corresponding to the region 12) are divided into two regions in which the movement of air is blocked between each other.

  The vent holes are provided at four locations, ie, the upper and lower portions of the upper region and the upper and lower portions of the lower region, but the vent holes 14 provided at the lower portion of the upper region are lower in the region. It is formed on the lower side in the vertical direction of the panel with respect to the vent hole 15 provided in the upper portion of the lower region on the side.

  By doing in this way, it is possible to prevent the air whose temperature has risen through the inside of the lower region from entering the upper region again like the vent hole of the second embodiment shown in FIG. The panel temperature can be effectively lowered by the outside air. The above-described effect in the present embodiment is that the lowermost vent hole is formed in the upper region portion, and the lowermost vent portion is formed in the lower region portion. As compared with the vent hole provided on the uppermost side, it is obtained in the same manner by being formed at the same height or lower side in the vertical direction of the panel.

  As described above, this embodiment is effective in obtaining a cooling effect by natural convection of the outside air, and the panel 2 is arranged in the left-right direction of the panel 2 depending on, for example, the arrangement of the built-in circuit board 6 and the structure of the chassis 5. If there is a difference in the amount of heat transmitted from the back cover 4 or the like, or if it is desired to divide the inner area of the back cover 4 in the left-right direction, or depending on the position of an obstacle in the back cover 4, such as the circuit board 6, This is considered to be particularly effective when the linear partition plate 8 cannot be formed up to both ends. In these cases, as shown in FIG. 9, in the two upper and lower regions divided by the partition plate 8, vent holes 13 and 14, and 15 and 16 provided at the upper and lower portions thereof are the panels. Needless to say, it is advantageous to form at least a part of the two in the left-right direction in order to shorten the air path inside each region.

  In addition, as shown in FIG. 9, the ventilation holes 17 are also provided in the side portions of the back cover 4 corresponding to the upper and lower portions corresponding to the respective regions, so that natural convection of outside air can be promoted more efficiently. It is considered effective for cooling the temperature of the panel 2. Further, in this way, the formation of the air hole in the side portion of the back cover is not limited to the third embodiment, and can be similarly applied to other plasma display panels 1 according to the present invention, It goes without saying that similar effects can be obtained.

  As mentioned above, although this invention has been demonstrated using embodiment, in dividing | segmenting the space inside the back cover 4 by the partition plate 8 in this invention, it divides | segments to the up-down direction by the partition plate 8, in other words, division | segmentation. It is important that the regions to be recognized can be recognized as those located on the upper side and those located on the lower side. In other words, if even a part of the area divided by the partition plate 8 is positioned above the part of the other area, the air path for cooling the inside of the area can be shortened in that part. Can be obtained.

  Moreover, although only the example divided into the upper and lower two regions by the partition plate 8 is shown, the present invention is not limited to this, and it is possible to divide into two or more regions such as three or four.

  Furthermore, in the description of each of the above embodiments, the plasma display 1 that reduces the temperature of the panel 2 using only natural convection of outside air has been described in all cases, but the present invention is not limited to this. It can also be applied to the case where the temperature inside the back cover is forcibly cooled using a fan. That is, the partition plate 8 divides the space inside the back cover 4 into a plurality of vertical regions, and with the help of a fan in all of these regions, or in those regions that particularly require temperature reduction measures. Inhalation and discharge of outside air can be accelerated, and in that case, a synergistic effect with the effect of the present invention can be expected.

  Further, in the above description of the present invention, as an example of an image display device, a description has been given using a plasma display in which heat generation of the panel is an important problem due to its operation principle, but the present invention is limited to this. However, the present invention can be applied to a liquid crystal display, a so-called cold cathode display, an EL display, and the like, and the same effects can be obtained.

  INDUSTRIAL APPLICABILITY The present invention is effective in suppressing an increase in the temperature of the back cover internal space in an image display device using a flat image display panel, and is particularly useful for a plasma display using a plasma display panel.

A perspective view showing an image display device Schematic sectional view of an image display device according to the present invention The figure which shows the back cover of the image display apparatus which concerns on the 1st Embodiment of this invention. The figure which shows the other example of the back cover of the image display apparatus which concerns on the 1st Embodiment of this invention. The figure which shows the back cover of the image display apparatus which concerns on the 2nd Embodiment of this invention. Temperature contour diagram showing the panel surface temperature distribution of the image display device according to the present invention Temperature contour diagram showing the panel surface temperature distribution of a conventional image display device Diagram showing circuit board layout used for panel temperature calculation The figure which shows the back cover of the image display apparatus which concerns on the 3rd Embodiment of this invention. Schematic sectional view of a conventional image display device The figure which shows the back cover of the conventional image display apparatus

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image display apparatus 2 Panel 3 Front cover 4 Back cover 5 Chassis 6 Circuit board 7 Resin sheet 8 Partition plate 10 Air flow 11 Upper area | region 12 Lower area | region 13 Upper ventilation hole 14 of upper area | region Lower ventilation hole of upper area | region 15 Ventilation hole at the upper part of the lower region 16 Venting hole at the lower part of the lower region 17 Venting hole provided on the side surface of the back cover 19 Upper ventilation hole 19 in the conventional image display device 19 Lower ventilation hole 20 in the conventional image display device Space inside back cover in conventional image display device

Claims (1)

A panel that displays an image; a chassis that supports the panel on the front surface; a plurality of circuit boards that are fixed to the rear surface of the chassis with a predetermined gap; and a front cover and a back cover that house these inside. An image display apparatus, wherein the gap between the chassis and the back cover is blocked at a position where the circuit board is not disposed between the chassis and the back cover so that air movement is blocked, and the back cover A partition plate that divides an internal space into a plurality of regions in the vertical direction is provided, and the back cover has a plurality of vent holes provided so as to correspond to the regions divided by the partition plate. An image display device.

Images