JP3975506B2 - Liquid crystal display device and cooling method of lamp part of liquid crystal display device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a liquid crystal display device capable of radiating heat from a lamp efficiently and without deteriorating dustproofness, and a cooling method for a lamp portion of the liquid crystal display device .
[0002]
[Prior art]
As a heat dissipation measure in a device equipped with a lamp, in the case of air cooling, a cooling method using natural convection or forced convection is used.
[0003]
For example, in a display device having a backlight, the following methods are known.
[0004]
(1) A method of cooling by directly applying external air to the lamp (2) A method of cooling the lamp by temporarily transferring the heat of the lamp to another member and then applying air to the member.
[0005]
The method (1) is a direct air cooling method. For example, as shown in the apparatus a of FIGS. 8 and 9, a plurality of lamps c, c,... The reflectors d are disposed behind them, and the fans e and e for blowing are disposed below these members. A dust-proof filter f is disposed under the fans e and e so that dust does not enter the apparatus. Openings g and g are formed between the display part b and the reflection plate d at the upper and lower parts of the lamps c, c,... As shown in FIG. 4, the lamp is formed so that it passes between the display part b and the reflector d and blows upward from the opening g, whereby the heat of the lamps c, c,. Become.
[0006]
The method (2) is an indirect air cooling method. For example, as shown in the apparatus of FIG. 10, the radiation fins i and i are respectively placed at predetermined positions on both side surfaces of the housing portions h of the lamps c, c,. By attaching the heat, the heat of the lamps c, c,... Is conducted to the heat radiation fins i, i and then radiated to the outside of the apparatus.
[0007]
[Problems to be solved by the invention]
Incidentally, the above-described method has the following problems in terms of dust resistance and cooling efficiency.
[0008]
That is, the method (1) has a disadvantage that dust easily enters the apparatus due to direct application of outside air to the lamp. Therefore, it is necessary to use a member such as the filter f for dust prevention. However, in the case of performing forced air cooling using a fan, there remains a problem that the dust-proof member causes a windage loss.
[0009]
Further, in the method (2), there is no problem of dust prevention as in the method (1). However, since heat is easily generated in the apparatus, the cooling efficiency is low, and the heat is transferred to another member. Since a material with good conductivity must be selected, the range of material selection is narrowed, which hinders freedom of design.
[0010]
Therefore, an object of the present invention is to provide a lamp cooling mechanism and method having high cooling efficiency without deteriorating the dustproof property.
[0011]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention is arranged in a horizontally-long rectangular box-shaped storage unit whose front and rear surfaces are open, a liquid crystal display unit disposed on the front surface of the storage unit, and a rear surface of the storage unit. a reflector unit for reflecting light forward, an internal housing portion between the reflecting plate portion liquid crystal display unit, arranged in the vertical direction with a predetermined interval, the central axes of the plurality extending in a horizontal direction The lamp part and the right and left side surfaces of the housing part, which has a height substantially equal to the height of the housing part, are airtight or hermetically sealed by the liquid crystal display part and the reflecting plate part so that air outside the apparatus does not enter. After the air heated by the lamp unit from the upper part of the housing part by natural convection flows into the outside, the heat of the heated air is radiated from the housing to the outside and cooled. two ducts in which the U-shaped air flow out to the bottom of the housing portion Has bets, air of the accommodating portion and the duct portion are those isolated from the outside. Alternatively, a horizontally-long rectangular box-shaped storage unit with the front and rear surfaces open, a liquid crystal display unit disposed on the front surface of the storage unit, and a reflector plate disposed on the rear surface of the storage unit and reflecting light forward , an internal housing portion between the reflecting plate portion liquid crystal display unit, arranged in the vertical direction with a predetermined interval, and a plurality of ramps which central axis extends in the horizontal direction, the height of the accommodating portion substantially Each end is fixedly connected to the left and right side surfaces of the housing part that has the same height and is airtight or sealed between the liquid crystal display part and the reflector part so that air outside the apparatus does not enter . A cooling method for a lamp part of a liquid crystal display device having a duct part, wherein the air in the accommodating part and the duct part is isolated from the outside, and air heated by the lamp part by natural convection from the upper part of the accommodating part An inflow step to be introduced into the duct section and an inflow step. A cooling step of heat dissipating cooled outside the heat of the heated air that is allowed to flow into the duct portion from the housing of the duct section in flops, outflow step of discharging the air that has been cooled in the cooling step to the lower housing portion It has.
[0012]
Therefore, according to the present invention, the cooling space of the duct portion communicating with the accommodating portion that is airtight or hermetically sealed by the liquid crystal display portion and the reflector plate portion, and the air in the lamp accommodating portion are isolated from the air outside the apparatus. Therefore, there is no need for a dust-proof member, the cause of windage loss during forced air cooling is eliminated, and the air heated by the lamp from the lamp housing is introduced into the duct from the top of the housing. Since the air is cooled and then returned to the lower part of the lamp housing, heat is not generated in the housing. And since the air in the accommodating part heated by the lamp is cooled by natural convection in a state where it is isolated from the outside, the cooling efficiency can be increased, and for that purpose, the range of material selection for the accommodating part Does not narrow. And since the temperature distribution in the housing part of the lamp is made uniform, for example, when using a plurality of lamps, there is no disparity in the brightness of each lamp, and uniform irradiation light can be obtained, and the lamp Variations in life can be reduced. Further, by attaching the duct portion to the end portion in the direction along the longitudinal direction of the lamp in the housing portion, the depth of the apparatus can be prevented from increasing with the attachment of the duct portion.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a basic configuration of an apparatus according to the present invention. In the apparatus 1, the cooling mechanism 2 has an accommodating part 4 for accommodating lamps 3, 3,. After the air heated by is introduced, the cooling unit 5 is configured to cool the air and return it to the housing unit 4.
[0014]
The device 1 includes a device that directly uses lamp light and a device that uses lamp light as display light. Examples of the former include illumination lamps and the like, and examples of the latter include devices (image display devices, advertising lights, etc.) provided with display means including a backlight (display devices, translucent display plates, etc.). In the present invention, lamp light is used as display light. The type of the lamp 3 can be applied to various lamps that emit light and generate heat, and the number of lamps to be used is not limited.
[0015]
The cooling part 5 has a cooling space 5a communicating with the housing part 4, and the air in the cooling space 5a and the housing part 4 is isolated from the air outside the apparatus. Therefore, the air in the housing part 4 heated by the heat generated by the lamp 3 moves to the cooling space 5a of the cooling part 5, and then moves into the housing part 4 after being cooled here. The air warmed by the heat generated by the lamp 3 moves upward, and the air cooled by the cooling unit 5 moves downward, so that air is introduced into the cooling unit 5 from the upper part of the housing unit 4 and cooled. It is preferable to employ a configuration in which air is returned from the portion 5 to the lower portion of the accommodating portion 4. At that time, if a filter or the like is provided at the communication part between the cooling part 5 and the accommodating part 4, convection is hindered or windage loss of the air blowing means described later is caused. In the present invention, such a member is provided. It is desirable to reduce the ventilation resistance of the communication part as much as possible.
[0016]
The casing 5b of the cooling unit 5 is formed using a material having a good thermal conductivity, for example, a metal material or a ceramic material. In particular, by using a metal material such as aluminum or copper, the casing 5b The heat of the lamp 3 can be efficiently radiated outside the apparatus.
[0017]
In addition to natural convection , the cooling unit 5 can further improve the heat dissipation effect by providing the heat dissipation means 6 or the air blowing means 7 as shown in FIG. The heat dissipating means 6 includes heat radiating fins and other members (heat dissipating members) for expanding the heat dissipating area, heat exchangers such as heat pipes, and cooling means (for example, cooling / heating means such as Peltier elements). It is. The air blowing means 7 includes all means for forced air circulation such as a fan.
[0018]
In addition, as shown in FIG. 3, forming a space in the pipes 8 and 8 or the cooling space 5 a that connects the accommodating portion 4 and the cooling portion 5 in a labyrinth is a factor that increases the heat dissipation effect. If this is not done, it will cause an increase in ventilation resistance.
[0019]
3 is a view of the cooling mechanism as viewed from the longitudinal direction of the lamps 3, 3,..., And when the display means 9 is disposed in front of the lamp 3 (the direction indicated by the arrow “F”), the lamp 3 Since the cooling unit 5 is located behind the device, the depth “W” of the apparatus becomes large. Therefore, in order to reduce this W, as shown in FIG. 1, it is preferable to attach the cooling part 5 to the end part in the direction along the longitudinal direction of the lamp 3 in the accommodating part 4, and such an arrangement is as follows. It is suitable for an apparatus having an advantage of thinness such as a plasma display.
[0020]
Thus, according to the present invention, the air in the accommodating portion 4 of the lamp 3 and the cooling space 5a communicating with the accommodating portion 4 is isolated from the air outside the apparatus, and the air heated by the lamp 3 is exchanged with the accommodating portion 4 of the lamp. After the air is introduced into the cooling space 5a, the air is cooled and then returned to the lamp accommodating portion 4, so that a dustproof member is unnecessary and heat is generated in the accommodating portion 4. The cooling efficiency can be increased by releasing the heat of the lamp 3 to the outside by the heat radiation in the cooling space 5a. And since the temperature distribution in the accommodating part 4 becomes uniform, the brightness of a lamp | ramp can be equalized (that is, if the temperature of the upper part of the accommodating part 4 is high, the brightness of the lamp located upward will become downward. Inconveniences such as darkening as compared with the brightness of the lamp located at.
[0021]
【Example】
Hereinafter, an embodiment in which the present invention is applied to an apparatus having a backlight cooling mechanism will be described with reference to FIGS. 4 to 7 together with a basic configuration example thereof.
[0022]
In the apparatus 10, the accommodating portion 12 of the lamps 11, 11,... Has a horizontally long rectangular box shape, and the lamps 11, 11,... Are disposed between the display portion 13 and the reflection plate 14 (see FIG. 5). .. are arranged at predetermined intervals in the vertical direction. In addition, the inside of the accommodating part 12 is made into an airtight or sealed state, so that air outside the apparatus does not enter the accommodating part 11.
[0023]
A liquid crystal display device is used for the display unit 13, and a cylindrical fluorescent lamp is used for the lamp 11 that irradiates the backlight to the display unit 13, and its central axis is in the horizontal direction. It is arranged to extend.
[0024]
The reflecting plate 14 for reflecting the lamp light to the display unit 13 side is preferably a metal material from the viewpoint of heat resistance and heat dissipation, but is not limited thereto, and other materials such as a ceramic material can be used. .
[0025]
In the apparatus 10, as shown in FIG. 4, the cooling units 15 and 15 are made of metal ducts 16 and 16 attached to both side surfaces (both ends in the longitudinal direction of the lamp 11) of the housing unit 12 (the above-described housing 5b). It is formed by. The U-shaped ducts 16 and 16 have one end portions 17 and 17 coupled to the upper part of the side surface of the accommodating portion 12, and communication holes 17 a and 17 a are formed between the accommodating portions 12. The other end portions 18 and 18 are coupled to the lower portion of the side surface of the accommodating portion 12, and communication holes 18 a and 18 a are formed between the other end portions 18 and 18 and the accommodating portion 12.
[0026]
The air heated by the heat of the lamp 11, as shown by the arrow in FIG. 4, is carried to the upper part in the accommodating part 12, and then moves into the ducts 16 and 16 through the communication holes 17a and 17a. Cooled by heat dissipation. And the cooled air moves in the accommodating part 12 through the communicating holes 18a and 18a, and the lamp | ramp 11 is cooled by this.
[0027]
In this configuration, circulation by natural convection is used. However, in addition to circulation by natural convection, as shown in the apparatus 10A in FIG. 6, the fans 19 and 19 are forcibly attached to the ducts 16 and 16, respectively. When the air is circulated between the accommodating portion 12 and the cooling portions 15 and 15 (see the arrows in the figure), the temperature of the lamps 11, 11,. And the brightness can be increased. And the temperature of lamp | ramp 11,11 ... is equalized and the temperature difference between the upper and lower sides in the accommodating part 12 becomes small, Therefore The lamp life and the variation in a brightness | luminance can be reduced.
[0028]
Further, as shown in the apparatus 10B of FIG. 7, the cooling parts 15 and 15 are provided by attaching the heat radiation fins 20 and 20 to the ducts 16 and 16 or expanding the heat radiation area by the shape design of the ducts 16 and 16, respectively. The heat dissipation efficiency can be increased.
[0029]
【The invention's effect】
As apparent from the above description, according to the first and fourth aspects of the invention, the cooling of the duct portion communicating with the accommodating portion that is hermetically or hermetically sealed between the liquid crystal display portion and the reflecting plate portion. Since the air in the space and the lamp housing is isolated from the air outside the device, a dust-proof member is unnecessary, the cause of windage damage during forced air cooling is eliminated, and the lamp is heated from the lamp housing. Since the air thus introduced is introduced into the duct part from the upper part of the housing part, the air is cooled and then returned to the lower part of the housing part of the lamp, so that no heat is generated in the housing part . And since the air in the accommodating part heated by the lamp is cooled by natural convection in a state where it is isolated from the outside, the cooling efficiency can be increased, and for that purpose, the range of material selection for the accommodating part Does not narrow. And since the temperature distribution in the housing part of the lamp is made uniform, for example, when using a plurality of lamps, there is no disparity in the brightness of each lamp, and uniform irradiation light can be obtained, and the lamp Variations in life can be reduced. Moreover, by attaching a duct part to the end part in the direction along the longitudinal direction of the lamp in the housing part, the depth of the apparatus can be prevented from increasing with the attachment of the duct part.
[0030]
According to the invention which concerns on Claim 2, the heat | fever of a lamp | ramp can be efficiently thermally radiated from this housing | casing to the exterior by forming the housing | casing of a duct part with a metal material.
[0031]
According to the invention which concerns on Claim 3 , the efficiency of heat dissipation can be achieved by providing a heat radiating means or a ventilation means in a duct part .
[Brief description of the drawings]
FIG. 1 is a conceptual diagram showing a basic configuration of an apparatus according to the present invention.
FIG. 2 is a conceptual diagram showing a configuration in which a heat dissipating unit and a blowing unit are provided in a cooling unit.
FIG. 3 is a conceptual diagram illustrating an example in which a cooling unit is configured in a maze shape.
FIG. 4 shows an embodiment together with FIGS. 5 to 7 together with an example of the basic configuration of the present invention . FIG. 4 is a schematic sectional view when the apparatus is cut along a vertical plane along the longitudinal direction of the lamp. It is.
FIG. 5 is a schematic cross-sectional view when the apparatus is cut along a vertical plane perpendicular to the longitudinal direction of the lamp.
FIG. 6 is a diagram showing a configuration in which a fan is attached to a cooling unit.
7 is a diagram showing a configuration in which heat dissipating fins are further provided in the configuration of FIG. 6;
FIG. 8 shows a conventional configuration example together with FIG. 9, and is a schematic cross-sectional view when the apparatus is cut along a vertical plane along the longitudinal direction of the lamp.
FIG. 9 is a schematic cross-sectional view of the apparatus cut along a vertical plane perpendicular to the longitudinal direction of the lamp.
FIG. 10 is a schematic cross-sectional view showing a conventional configuration example in which a heat radiating fin is attached to a lamp housing portion.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Apparatus, 3 ... Lamp, 4 ... Accommodating part, 5 ... Cooling part, 5b ... Housing | casing, 6 ... Radiating means, 7 ... Air blower , 11 ... Lamp part, 12 ... Accommodating part, 13 ... Liquid crystal display part, 14 ... reflector plate, 16 ... duct part, 17 ... one end part (end part), 18 ... other end part (end part), 19 ... air blowing means, 20 ... heat dissipation means

Claims (4)

A horizontally-long square box-shaped storage unit with the front and rear surfaces open,
A liquid crystal display disposed on the front surface of the housing;
A reflector plate disposed on the rear surface of the housing portion and reflecting light forward;
A plurality of lamp portions arranged in the vertical direction at a predetermined interval between the liquid crystal display portion and the reflection plate portion inside the housing portion, the central axis extending in the horizontal direction;
Each of the left and right side surfaces of the housing portion has a height substantially equal to the height of the housing portion and is airtight or sealed between the liquid crystal display portion and the reflector plate so that air outside the apparatus does not enter. After the air heated by the lamp unit from the upper part of the housing part is allowed to flow by natural convection, the heat of the heated air is radiated from the housing to the outside and cooled. , Two U-shaped duct parts that flow out the cooled air to the lower part of the housing part,
The liquid crystal display device, wherein air in the housing part and the duct part is isolated from the outside. 2. The liquid crystal display device according to claim 1, wherein the casing of the duct part is formed of a metal material, and heat of air heated by the lamp part is radiated from the casing to the outside. The liquid crystal display device according to claim 1, wherein a heat radiating unit or a blower unit is provided in the duct portion. A horizontally-long rectangular box-shaped storage unit with an open front surface and a rear surface, a liquid crystal display unit disposed on the front surface of the storage unit, a reflector unit disposed on the rear surface of the storage unit and reflecting light forward A plurality of lamp units arranged in the vertical direction with a predetermined interval between the liquid crystal display unit and the reflection plate unit inside the storage unit, the central axis extending in the horizontal direction, and the storage unit The end portions on the left and right side surfaces of the housing portion are substantially equal to the height of the liquid crystal display portion and are airtight or sealed between the liquid crystal display portion and the reflection plate portion so that air outside the apparatus does not enter. A cooling unit for a lamp part of a liquid crystal display device, wherein the housing part and the air in the duct part are isolated from the outside.
An inflow step for causing air heated by the lamp portion by natural convection to flow into the duct portion from an upper portion of the housing portion ;
A cooling step in which the heat of the heated air that has flowed into the duct portion in the inflow step is radiated from the casing of the duct portion to the outside and cooled;
An outflow step of flowing out the air cooled in the cooling step to a lower portion of the housing portion. A method for cooling a lamp unit of a liquid crystal display device.

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