KR100920827B1 - Coling system of lcd device - Google Patents

Abstract

PURPOSE: A cooling system of an LCD device is provided to improve the heat-radiation characteristic of the front and rear sides of a backlight. CONSTITUTION: A cooling system of an LCD device comprises a liquid crystal panel(130), a backlight unit(120), a case(110), a front side flow channel, a rear side flow channel and a connection flow channel. The backlight unit is equipped at the back side of the liquid crystal panel. The case surrounds the circumference of the liquid crystal panel and backlight unit. An exposure hole is formed on the case so that the front side of the liquid crystal panel can be exposed. The front side flow channel is formed so as to make the airflow possible.

Description

Cooling system of LCD device {Coling system of LCD device}

The present invention relates to a cooling system of an LCD device, and more particularly, to form front and rear flow paths through which air can flow before and after a backlight unit, and by flowing air cooled through a flow path by an air circulation unit to dissipate heat radiation of the LCD device. It relates to a cooling system of the LCD device to improve the.

The liquid crystal display displays an image by using electrical and optical characteristics of the liquid crystal. Liquid crystal displays have the advantages of being very small in volume and light in weight compared to cathode ray tubes (CRTs). As a result, they are widely used in portable computers, communication devices, liquid crystal televisions, and aerospace industries.

The liquid crystal display device includes a liquid crystal controller for controlling liquid crystal and a backlight for supplying light to the liquid crystal. The liquid crystal controller includes a pixel electrode disposed on the first substrate, a common electrode disposed on the second substrate, and a liquid crystal interposed between the pixel electrode and the common electrode. The pixel electrode is formed in plural in correspondence with the resolution, and the common electrode is made of one and facing the pixel electrode. A thin film transistor (TFT) is connected to each pixel electrode to apply a pixel voltage having a different level, and a reference voltage of the same level is applied to the common electrode. The pixel electrode and the common electrode are made of a transparent material having conductivity.

Light supplied from the backlight sequentially passes through the pixel electrode, the liquid crystal, and the common electrode. In this case, the display quality of the image passing through the liquid crystal largely depends on the luminance and luminance uniformity of the rear light source. In general, the higher the luminance and the uniformity of the luminance, the better the display quality.

Conventionally, a backlight of a liquid crystal display device mainly uses a cold cathode fluorescent lamp (CCFL) having a rod shape or a light emitting diode (LED) having a dot shape. Cold cathode ray tube lamp has the advantage of high brightness, long life, and very low heat generation compared to incandescent lamps. On the other hand, the light emitting diode has the advantage of high power consumption but high luminance. However, cold cathode ray tube type lamps or light emitting diodes have poor brightness uniformity. Therefore, the rear light source having the cold cathode ray tube lamp or the light emitting diode as the light source has uniform luminance.

In order to increase the properties, optical members such as a light guide panel (LGP), a diffusion member, a prism sheet, and the like are required. As a result, a liquid crystal display using a cold cathode ray tube lamp or a light emitting diode has a problem in that the volume and weight of the optical member are greatly increased.

As a backlight for a liquid crystal display device, a flat fluorescent lamp (FFL) as a surface light source has been proposed.

1 and 2 show the main components of the liquid crystal display device employing the surface light source 10 as a backlight. A rear surface light source 10 is disposed behind the liquid crystal panel 12 with the optical member 11 interposed therebetween, and the cases 20 and 22 are coupled to the front and rear surfaces, respectively, to form a system. A discharge voltage is applied from the driver 13 to the surface light source to transmit visible light to the front liquid crystal panel through discharge.

The problem of heat dissipation of the backlight in a liquid crystal display device is very serious in terms of display quality and lifetime of the device. The surface light source generates severe heat due to the discharge, and the gap between the liquid crystal panel and the surface light source is very narrow, and each component is closely coupled to each other as shown in FIG. 3 to realize a thin display.

As the size of the liquid crystal display device increases, it is necessary to solve the heat radiation problem of the surface light source.

Although it is a major technical task, no effective alternative has been proposed.

Conventionally, heat dissipation is difficult by the optical member and the liquid crystal panel in the front part of the backlight, and the rear part of the backlight is also blocked by the rear case, which makes heat dissipation difficult. Currently, the backlight mounted on the large-area LCD displays severe heat generation due to high voltage discharge, but there is no heat dissipation means other than heat transfer through the contact area with the rear case, so localized heat concentration or temperature gradient is induced. There is a problem such as causing a luminance unevenness during operation, thereby shortening the lifetime and product reliability is low.

Therefore, there is a need for improvement.

The present invention is created by the necessity as described above, by forming a flow path through which air can flow in the front and rear of the backlight, respectively, by circulating and cooling the air in the flow path provided in the rear of the case, It is an object of the present invention to provide a cooling system of an LCD device that improves heat dissipation.

The cooling system of the LCD device according to the present invention includes a liquid crystal panel, a backlight unit which is provided on the rear side of the liquid crystal panel and supplies a light source to the liquid crystal panel, and wraps around the liquid crystal panel and the backlight unit so that the front surface of the liquid crystal panel is exposed. The front channel is formed to form a case, and the liquid crystal panel and the backlight unit are spaced apart to allow air flow, and the rear channel is formed to be spaced apart from the back of the backlight unit and the case to allow air flow. Connection flow paths formed at upper and lower edges of the backlight unit to be spaced apart from the case so that the flow paths are connected to each other, and an air circulation unit and air that are provided at the rear of the case to circulate air through the rear flow path and the front flow path and cool the circulated air. The rear flow path is provided so that air circulated by the circulation portion enters the front flow path through the rear flow path. It includes Ryan walls.

The gap maintaining member is interposed between the backlight unit and the liquid crystal panel to form a front flow path.

The air circulation unit is provided at the rear side of the case, and is provided in the interior of the guide case, a first circulation fan that guides the air sucked by the first circulation fan, a first circulation fan that sucks air entering the rear flow path through the front flow path, and the inside of the guide case. And a second circulation fan configured to heat the air circulated with the circulated air to cool the air, and to blow the air cooled by the heat radiating part into the rear flow path to circulate the front flow.

The heat dissipation unit may include a heat dissipation fin provided on the inner surface of the guide case and a heat absorbing portion of the thermoelectric element to widen the heat exchange area of air.

And, the guide case is characterized in that the discharge hole for emitting the heat of the heat generating portion of the thermoelectric element to the outside.

In addition, the discharge hole is characterized in that the heat radiation fan is further provided.

In addition, the upper surface of the guide case is characterized in that the heat sink made of aluminum so as to heat exchange with the outside air.

As described above, the cooling system of the LCD device according to the present invention, unlike the conventional invention forms a front flow path and a rear flow path through which air can flow, respectively, in the front and rear of the backlight, the flow path in the air circulation provided on the rear of the case By circulating the air, the heat dissipation of the front and rear of the backlight is improved to prevent luminance unevenness due to heat concentration or temperature gradient in the backlight.

Accordingly, durability and lifespan may be improved by preventing overheating during operation of the backlight or the liquid crystal display including the same.

In addition, the air circulated by the thermoelectric element having a heat dissipation fin on the side of the guide case is cooled, and the upper surface of the guide case is made of a heat sink made of aluminum to improve heat dissipation.

In addition, by forming a flow guide wall in the center of the rear channel, there is an advantage that can circulate a large amount of air to the front channel as well as the rear channel.

Hereinafter, a preferred embodiment of a cooling system of an LCD device according to the present invention with reference to the accompanying drawings. In this process, the thickness of the lines or the size of the components shown in the drawings may be exaggerated for clarity and convenience of description. In addition, terms to be described below are terms defined in consideration of functions in the present invention, which may vary according to the intention or convention of a user or an operator. Therefore, definitions of these terms should be made based on the contents throughout the specification.

Figure 4 is an exploded perspective view showing a cooling system of the LCD device according to an embodiment of the present invention, Figure 5 is a rear perspective view showing the inside in a combined state of the cooling system of the LCD device according to an embodiment of the present invention, 6 is a side cross-sectional view of a cooling system of the LCD device according to an embodiment of the present invention, Figure 7 is a view showing the air flow of the cooling system of the LCD device according to an embodiment of the present invention.

As illustrated, the cooling system of the LCD device according to the present invention includes a liquid crystal panel 120, a backlight unit 130 provided at a rear side of the liquid crystal panel 120, and a circumference of the liquid crystal panel 120 and the backlight unit 130. A case 110 having an exposure opening 113 formed to cover the front surface of the liquid crystal panel 120 and a front flow path formed between the liquid crystal panel 120 and the backlight unit 130 so as to allow air flow. The rear channel 150 and the rear channel 150 which are formed between the rear surface of the backlight unit 130 and the case 110 so as to allow air flow, and the rear channel 150 and the front channel 140 are connected to each other. Upper and lower edges of the backlight unit 130 are connected to the flow path 145 formed to be spaced apart from the case 110, and are provided at the rear of the case 110 to circulate air through the rear flow path 150 and the front flow path 140. And by the air circulation unit 160 and the air circulation unit 160 for cooling the air circulated. It includes a flow path guide wall 152 to allow the air circulated to flow into the connection flow path through the rear flow path (150).

The case 110 includes a front case 112 having an opening 113 in the center so that the liquid crystal panel 120 is exposed, and a rear case protecting the liquid crystal panel 120 and the backlight unit 130. 114).

It is preferable that the tempered glass 115 is provided between the front case 112 and the liquid crystal panel 120.

The backlight unit 130 includes a light guide plate disposed adjacent to the liquid crystal panel 120 and a light source for irradiating light to the light guide plate, and the light transmitted from the light source to the light guide plate is transferred to the liquid crystal panel through a diffusion plate and / or a prism. Guided to 120 side.

In addition, a space maintaining member 125 is interposed between the backlight unit 130 and the liquid crystal panel 120 to form a front flow path 140.

As shown in FIG. 4, the gap maintaining member 125 is interposed between edges of the backlight unit 130 and the liquid crystal panel 120 and is spaced apart from each other.

In addition, the rear surface of the backlight unit 130 and the rear case 114 are spaced apart to form a rear flow path 150, and the upper and lower portions of the backlight unit 130 are spaced apart from the upper and lower portions of the front case 112, respectively, and the front flow path ( The connection flow passage 145 is formed so that the 140 and the rear flow passage 150 are connected to each other.

In this case, a flow path guide wall 152 is formed on the central rear surface of the backlight unit 130 to protrude toward the rear case 114 to partition the upper and lower portions.

On the other hand, the air circulation unit 160 for circulating air through the front channel 140, the rear channel 150, the connection channel 145 formed as described above is provided on the rear of the case 110.

The air circulation unit 160 is provided at the rear of the case 110, and includes a first circulation fan 162 and a first circulation fan 162 that suck air that enters the rear channel 150 through the front channel 140. Cooling by the heat dissipation unit 165 and the heat dissipation unit 165 for guiding the air sucked by the air) and the heat exchanged with the circulated air provided in the guide case 164 to cool the air. It consists of a second circulation fan 168 for blowing the air into the rear flow path 150 to circulate to the front flow path 140.

The first circulation fan 162 is formed at the upper end of the rear case 114, the second circulation fan 168 is preferably formed at the lower end of the rear case 114.

The heat dissipation unit 165 includes a thermoelectric element 166 provided on the inner surface of the guide case 164 and a heat dissipation fin 167 provided on the heat absorbing portion of the thermoelectric element 166 to widen the heat exchange area of air.

The thermoelectric element 166 absorbs heat from a low temperature heat source and heats the high temperature heat source. When a direct current voltage is applied to both ends of the thermoelectric element 166, the heat moves from the heat absorbing portion to the heat generating portion.

That is, the first circulation fan 162 and the second circulation fan 168 are provided on the same line, and the heat absorbing portion of the thermoelectric element 166 is formed on the same line to exchange heat with air circulated. Therefore, the contact area is increased to improve heat exchange performance.

In addition, the side of the guide case 164 is preferably formed with a discharge hole (164a) for discharging the heat of the heat generating portion of the thermoelectric element 166 to the outside, the heat radiation fan 170 is formed in the discharge hole (164a). .

The upper surface of the guide case 164 is characterized in that the heat sink 163 made of aluminum so as to heat exchange with the outside air.

In order to improve heat exchange, the heat sink 163 has a plurality of pieces spaced apart from each other to widen the contact area with the external air, and the printed circuit board 180 is provided on the lower surface of the guide case 164 to transmit external data and power.

Hereinafter, the operation and effect of the cooling system of the LCD device according to an embodiment of the present invention.

First, when data and power are supplied to the printed circuit board 180 provided in the guide case 164, the first and second circulation fans 162 and 168 formed on the rear case 114 are rotated, and the thermoelectric element is rotated. A direct current voltage is applied to 166 to form an endothermic portion and an outer side heat generating portion.

In addition, the front channel 140 is formed between the backlight unit 130 and the liquid crystal panel 120 by the gap maintaining member 125, and the backlight unit 130 and the rear case 114 are separated from each other by the rear channel 150. ) Is formed, and the front passage 140 and the rear passage 150 are communicated with each other by the connection passage 145.

The first circulation fan 162 sucks air from the front channel 140 and the rear channel 150, and blows air into the front channel 140 and the rear channel 150 by the second circulation fan 168. It will be put.

That is, the first circulation fan 162 is formed in the upper portion of the rear case 114, the second circulation fan 168 is formed in the lower portion of the rear case 114, so that the flow of air from below to upward, the backlight The hot heat generated in the unit 130 is discharged through the upper portion, and after the heat exchange is introduced through the lower portion, has the advantage of smoothing the circulation of air.

At this time, the air sucked by the first circulation fan 162 is cooled by heat exchange with the heat absorbing portion of the thermoelectric element 166 formed on the inner surface of the guide case 164, and then the rear flow path by the second circulation fan 168. It passes through the 150 and flows into the front passage 140 to dissipate the LCD device 100.

The heat dissipation fin 167 is formed on the heat absorbing portion side of the thermoelectric element 166 to increase the heat exchange area with the circulating air to improve heat exchange performance.

This allows the air circulated by the first and second circulation fans 162 and 168 to be cooled by the thermoelectric element 166 even when the external temperature is high, thereby maximizing the heat dissipation effect.

In addition, a flow path guide wall 152 is formed in the backlight unit 130 to divide the rear flow path 150 into an upper part and a lower part so that air circulates through only the rear flow path 150 adjacent to the first and second circulation fans 162 and 168. It is to prevent the air to be circulated through the front passage 140 to maximize the heat dissipation.

On the other hand, the upper plate of the guide case 164 is made of a heat sink 163 made of aluminum heat exchange with the outside air to double the heat dissipation effect.

This is because the hot air heat-exchanged by the heat of the backlight unit 130 is discharged to the upper by the first circulation fan 162, the first heat exchange is made in the heat sink 163, and the second by the thermoelectric element 166 By heat exchange, the heat radiation effect is doubled.

In addition, a discharge hole 164a is formed at a side surface of the guide case 164, and a heat radiating fan 170 is provided at the heat generating part side discharge hole 164a of the thermoelectric element 166 to direct heat generated from the heat generating part to the outside. Release.

By forming a flow path through which air can be circulated in the front and rear of the backlight unit as described above, forcibly circulating the internal air by a fan, and cooling the air by the thermoelectric element during circulation, thereby maximizing the heat dissipation effect. have.

This can directly contribute to the improvement of display quality and lifespan of the LCD device 100.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely exemplary, and various modifications and equivalent other embodiments are possible to those skilled in the art. Will understand.

Therefore, the true technical protection scope of the present invention will be defined by the claims.

1 is an exploded perspective view showing a main configuration of a liquid crystal display according to the related art.

Figure 2 is a side view showing the main configuration of a conventional liquid crystal display device.

Figure 3 is a side view showing a backlight according to the prior art.

Figure 4 is an exploded perspective view showing a cooling system of the LCD device according to an embodiment of the present invention.

Figure 5 is a rear perspective view showing the inside in the combined state of the cooling system of the LCD device according to an embodiment of the present invention.

Figure 6 is a side cross-sectional view of a cooling system of the LCD device according to an embodiment of the present invention.

7 is a view showing the air flow of the cooling system of the LCD device according to an embodiment of the present invention.

<Description of Symbols for Main Parts of Drawings>

100: LCD device 110: case

112: front case 113: exposure opening

114: rear case 115: tempered glass

120: backlight unit 125: spacing members

130: liquid crystal panel 140: front euro

145: connection euro 150: rear euro

152: euro guide wall 160: air circulation

162: first circulation fan 163: heat sink

164: guide case 164a: discharge hole

165: heat dissipation unit 166: thermoelectric element

167: heat dissipation fin 168: second circulation fan

170: heat dissipation fan 180: printed circuit board

Claims (7)

A liquid crystal panel; A backlight unit provided on the rear side of the liquid crystal panel; A case surrounding the circumference of the liquid crystal panel and the backlight unit and having an exposed port to expose the entire surface of the liquid crystal panel; A front flow path spaced between the liquid crystal panel and the backlight unit to allow air flow; A rear flow path formed between the rear surface of the backlight unit and the case so as to allow air flow; A connection flow path formed at upper and lower edges of the backlight unit to be spaced apart from the case so that the rear flow path and the front flow path are vented with each other; An air circulation unit provided at a rear side of the case to circulate air through the rear channel and the front channel and to cool the air circulated; And And a flow path guide wall through which the air circulated by the air circulation part flows into the connection flow path through the rear flow path. The method of claim 1, Cooling system of the LCD device, characterized in that the spacer between the backlight unit and the liquid crystal panel to form a front surface path (spacer) is interposed. The method of claim 1, A first circulation fan provided at a rear surface of the case and sucking air entering the rear channel through the front channel; A guide case for guiding the air sucked by the first circulation fan; A heat dissipation unit provided inside the guide case and heat-exchanging with circulated air to cool the air; And a second circulation fan for blowing air cooled by the heat dissipation unit to the rear channel to circulate the front channel. The method of claim 3, wherein The heat dissipation unit is a thermoelectric element provided on the inner surface of the guide case; And Cooling system of the LCD device including a heat radiation fin provided on the heat absorbing portion of the thermoelectric element to widen the heat exchange area of the air. The method of claim 4, wherein Cooling system of the LCD device, characterized in that the guide case is formed with a discharge hole for emitting heat to the outside of the heat generating portion of the thermoelectric element. The method of claim 5, Cooling system of the LCD device characterized in that the discharge hole is further provided with a heat radiating fan. The method according to any one of claims 3 to 5, Cooling system of the LCD device, characterized in that the upper surface of the guide case is a heat sink made of aluminum so as to heat exchange with the outside air.

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