KR20000074192A - Radiating apparatus of Plasma Display Panel - Google Patents

Abstract

PURPOSE: A heat emitting device of a plasma display panel is provided to obtain a clear image in the plasma display panel by allowing the plasma display panel to have a uniform temperature distribution. CONSTITUTION: A heat emitting device of a plasma display panel comprises a heat conductive sheet(2) and a heat emitting plate(3) which are sequentially formed at a rear portion of a panel portion(1). The heat emitting plate(3) has at least one opening(3a) in such a manner that the heat emitting plate(3) can directly transfer the heat from the rear side of the panel portion(1) through the convection and radiation. The opening(3a) of the heat emitting plate(3) is positioned corresponding to a center of an upper portion of the panel portion(1) into which the heat is focused.

Description

Radiating apparatus of plasma display panel

The present invention relates to a plasma display panel, and more particularly, to a heat dissipation apparatus of a plasma display panel for smoothly dissipating heat generated during operation in order to stably maintain the operation of the plasma display panel.

In general, a plasma display panel (PDP) is a type of light emitting device in which two glass substrates are bonded and fixed with airtightness and display an image using a gas discharge phenomenon therein. There is no need to install an active element every time, so the manufacturing process is simple, the screen is easy to enlarge, and the response speed is fast.The direct-view image display device having a large screen, especially the image display device for HDTV (High Definition TeleVision) era. It is used for applications such as televisions, monitors, indoor and outdoor display devices.

In addition, the PDP is in the spotlight in a large (40 to 60 inch) display element region, in which two glass substrates are sealed by frit glass, and discharge gas is 100 to 600 Torr in the sealed structure. It is filled with the pressure of, and the main discharge gas currently used is helium (He) and penning gas including xenon (Xe).

In the image display section of the panel, the intersections of the plurality of electrodes correspond to each pixel (cell). During driving, a voltage of 100 volts or more is applied between the intersecting electrodes, and the gas is glow discharged to display an image using light emission at that time. In addition, the panel unit serves as a display element in combination with the driving unit.

Such PDPs are classified into two-electrode type, three-electrode type, and four-electrode type according to the number of electrodes assigned to each cell. Among them, the two-electrode type has two electrodes for addressing and sustaining. The voltage is applied together, and the three-electrode type is generally called a surface discharge type to be switched or maintained by a voltage applied to an electrode located on the side of the discharge cell.

On the other hand, the PDP inevitably generates a high temperature due to the gas discharge during driving, and the rapid heat dissipation is related to the stable operation and life of the PDP.

1 and 2 illustrate a heat dissipation device of a PDP according to the prior art, wherein a thermal conductive sheet 2 and a heat dissipation plate 3 are sequentially positioned on a rear surface of the panel 1 sealed by frittgrass. The position is fixed by the double-sided tape 4.

At this time, the thermal conductive sheet 2 is usually made of a silicone material with adhesiveness, and the heat sink 3 is usually made of a high thermal conductive aluminum material, the thermoelectric between the rear panel 1 and the heat sink 3 Adhesion of the conductive sheet 2, positioning the double-sided tape 4 around the thermal conductive sheet 3 to have a strong fixing force, and then applying sufficient compressive force to heat the heat generated from the panel portion 1 to the thermal conductive sheet 2 ) And the heat sink (3) to be easily conducted.

Here, the heat generated from the panel portion 1 is largely radiated through two paths, the first path is heat generated inside the panel portion 1 is passed through the panel by conduction of the panel portion 1 At the front surface, heat transfer by convection and radiation with the atmosphere occurs at the same time, and in the second path, heat generated inside the panel portion 1 passes through the panel and passes through the rear surface of the panel portion 1 through the thermally conductive sheet 2. And heat transfer by heat from the surface of the heat sink 3 to convection with the atmosphere and radiation to the PCB (not shown).

By the way, since an image is displayed on the front surface of the panel portion 1, the temperature cannot be adjusted artificially in this portion.

That is, the increase in the amount of heat dissipation through the rear surface of the panel unit 1, the thermal conductive sheet 2, and the heat sink 3 is closely related to the efficient heat dissipation of heat generated from the panel unit 1.

On the other hand, the heat dissipation device of the PDP according to the prior art has a high thermal conductivity to the rear of the panel portion, the thermal conductive sheet, and the heat sink, and also has high heat transfer due to convection between the heat sink surface and the atmosphere, but the emissivity due to radiation because the surface of the heat sink is smooth. Since this is considerably low as about 0.04, the heat transfer effect by radiation can hardly be expected.

Due to this heat transfer inconsistency, heat generated from the panel part is not completely radiated and residual heat is concentrated on a part of the area. Since the outer part of the panel part is close to the atmosphere, heat can be radiated smoothly by convection. Because the site is far from the atmosphere, heat transfer due to convection is relatively poor. In addition, since heat has a property of rising, a concentration phenomenon of residual heat has occurred in the center upper end portion 1a when the panel portion is faced as shown in FIG. 3.

In this way, since the temperature difference between the central upper end portion 1a of the panel portion in which the heat is concentrated is severely different from other portions, the deterioration of components such as phosphors and electrodes in the PDP during long periods of time may not be able to provide a clear image. In addition, there is concern about deflation.

Accordingly, the present invention has been proposed in view of the above, and provides a heat dissipation device of a plasma display panel that maximizes the overall heat dissipation by improving heat transfer efficiency by radiation as well as heat transfer by convection in performing heat dissipation through a back substrate. Its purpose is to.

1 is an exploded perspective view of a heat radiator of a conventional plasma display panel;

2 is a cross-sectional view of a heat radiation device coupled to a conventional plasma display panel;

3 is a temperature distribution diagram of a conventional plasma display panel,

4 is an exploded perspective view of a heat radiator of a plasma display panel according to the present invention;

5 is a cross-sectional view illustrating a heat radiation device coupled to the plasma display panel according to the present invention.

*** Explanation of symbols for main parts of drawing ***

1: Panel part 1a: Center upper part of panel part

2: thermally conductive sheet 2a: opening of thermally conductive sheet

3: heat sink 3a: opening part of heat sink

4: double sided tape

The heat dissipation device of the plasma display panel according to the present invention for achieving the above object is a plasma display in which the thermal conductive sheet and the heat sink are sequentially positioned on the rear surface of the panel unit in order to dissipate heat generated during driving of the panel unit which is an image display surface. In the panel: The heat sink is characterized in that the panel portion has at least one opening so as to allow direct convection heat transfer and radiant heat transfer.

Preferably, the opening is located at a portion corresponding to the central upper portion of the panel portion where heat is concentrated.

Optionally, the thermally conductive sheet is characterized in that the location portion corresponding to the opening is opened.

In this way, the heat generated from the panel portion is conducted to the thermally conductive sheet and the heat sink to provide convective and convective heat transfer and weak radiant heat transfer from the surface of the heat sink, and the panel portion is directly convection through the opening of the thermal conductive sheet and the heat sink. Heat transfer and radiant heat transfer are possible.

As a result, the temperature of the panel portion can be maintained at an appropriate level, and in particular, it is possible to smoothly dissipate heat of the central upper portion of the panel portion where heat is concentrated, thereby improving the reliability of the product.

And, there may be a plurality of embodiments of the present invention, hereinafter will be described in detail with respect to the most preferred embodiment.

This preferred embodiment allows for a better understanding of the objects, features and advantages of the present invention.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the heat radiating device of the plasma display panel according to the present invention.

In addition, in drawing used for description, about the component same as FIG. 1 thru | or FIG. 3, the same code | symbol may be attached | subjected, and the overlapping description may be abbreviate | omitted.

As shown in FIGS. 4 and 5, the heat dissipation device of the plasma display panel according to the present invention is a thermally conductive sheet positioned at the rear side of the panel unit 1 to dissipate heat generated during driving of the panel unit 1. Openings 2a and 3a are formed in (2) and the heat sink 3, and the openings 2a and 3a are arranged above the center of the panel portion 1 where heat is concentrated.

As described above, the panel unit 1 generates a high temperature due to a gas discharge phenomenon during driving, and rapidly dissipating such heat is related to stable driving and life of the PDP.

Here, when the heat dissipation method according to the prior art is described, heat from the panel portion 1 is conducted to the thermal conductive sheet 2 and the heat dissipation plate 3, and convective heat transfer and radiant heat transfer from the surface of the heat dissipation plate 3 are described. To dissipate heat.

Theoretically calculating the heat dissipation at this time by taking the temperature of each part experimentally measured from 42 "wide PDP as an example, the heat sink 3 temperature is 52.4 ℃, the ambient air temperature is 43.1 ℃, and the PCB average temperature is 44.5 ℃. In this case, the convective heat transfer rate on the surface of the heat sink 3 is about 15.5W, and the radiant heat transfer rate is about 1.21W, so the total heat dissipation from the heat sink 3 is about 16.7W.

Here, the reason for the convective heat transfer rate >> radiant heat transfer rate is that the emissivity due to radiation decreases to about 0.04 because the surface of the heat sink 3 is smooth, so that the effect due to the radiation has little effect.

Therefore, it can be seen that it is ideal to obtain both the heat transfer effect by convection and the heat transfer effect by radiation in order to increase the amount of heat radiation from the above-described prior art.

The present invention is applied to the above theory, a method for greatly increasing the amount of heat dissipation of heat generated from the panel portion 1, a method for greatly reducing the conductive thermal resistance of the thermal conductive sheet 2 and the heat sink 3, and the heat sink ( The method of increasing the heat dissipation by changing the structure of 3) can be mentioned, and the latter is applied.

That is, when the openings 2a and 3a are formed in the thermal conductive sheet 2 and the heat sink 3, the rear surface of the panel 1 in this region is in direct contact with the outside air, and thus heat can be transferred by the outside air and convection. . In addition, since the rear part of the panel 1 of this part is directly shaped to the PCB not shown in the drawing, heat transfer by radiation to the PCB substrate is possible.

In addition, in the portion where the openings 2a and 3a are not formed, the heat generated from the panel 1 is conducted to the thermal conductive sheet 2 and the heat sink 3 so that heat transfer and minute radiation by convection as in the prior art. Heat transfer by

Theoretically calculating the heat dissipation amount at this time by taking the temperature of each part experimentally measured from a 40 "PDP as an example, the temperature of the panel part 1 is 55 degreeC, the heat sink 3 temperature is 52.4 degreeC, and the ambient air temperature is At 43.1 ℃ and PCB's average temperature is 44.5 ℃, the heat transfer rate by convection becomes 18.04W, which is the sum of the convective heat transfer rate (8.50W) directly from the panel 1 and the heat transfer rate (9.54W) from the heat sink 3 surface. The heat transfer rate by radiation becomes 16.9W, which is the sum of the radiation heat transfer rate 16.2W directly from the panel unit 1 and the radiation heat transfer rate 0.74W from the surface of the heat sink 3, so that the total heat dissipation is 35W.

Accordingly, when comparing the heat dissipation amount according to the present invention with the heat dissipation amount according to the present invention, the heat transfer rate due to convection is increased about 14.1%, and the heat transfer rate due to radiation is increased about 93%. It shows an improvement of about 52.3%.

This is a comparison of the heat dissipation amount according to a specific PDP model, it is obvious that the above numerical value does not apply to all models, but shows a significant heat dissipation increase effect.

On the other hand, when comparing the overall temperature distribution of the panel portion 1, the temperature of the center upper end (1a), which is the high temperature part and the lowest end of the low temperature part is 5 ~ 7 ℃ difference in the case of 40 "PDP, according to the present invention When the openings 2a and 3a of the thermal conductive sheet 2 and the heat sink 3 are disposed at the same position as the central upper end 1a of the panel portion 1, which is a high temperature portion, the panel portion 1 is directly Convection and radiative heat transfer effects can be increased to show concentrated cooling effects.

In fact, when the openings 2a and 3a are disposed at the same position as the central upper end portion 1a of the panel portion 1, it exhibits a cooling effect of about 5 ° C at this portion, and thus the entire panel portion 1 The temperature distribution becomes uniform.

In addition, although specific embodiments of the present invention have been described and illustrated above, it is obvious that the present invention may be variously modified and implemented by those skilled in the art.

Such modified embodiments should not be individually understood from the technical spirit or the prospect of the present invention, and such modified embodiments should fall within the appended claims of the present invention.

It is clear from the above description that, according to the present invention, the average heat dissipation amount is increased in the entire panel part, and thus, stable driving and lifespan are extended. In this part, deterioration of components is prevented, and the effect is that a clear image can be provided on the entire display screen.

Claims (3)

In a plasma display panel in which a thermally conductive sheet and a heat sink are sequentially positioned on a rear surface of the panel unit to dissipate heat generated during driving of the panel unit, which is an image display surface: The heat sink is, And at least one opening to allow convective heat transfer and radiant heat transfer directly from the rear surface of the panel unit. The method of claim 1, And the opening is positioned at a portion corresponding to a central upper portion of the panel portion where heat is concentrated. The method according to claim 1 or 2, The heat conductive sheet of the plasma display panel, characterized in that the position portion corresponding to the opening is opened.