JP4656418B2 - Lighting device and image display device - Google Patents

Description

  The present invention relates to the technical field of lighting devices and image display devices. More specifically, the present invention relates to a technical field in which a guide member that guides cooling air to heat radiating fins is arranged to improve cooling efficiency.

  For example, there is an illuminating device that performs illumination using a plurality of light sources such as light emitting diodes. For example, the illumination device is used as an illumination device using a light source as direct illumination, or used in an image display device such as a television receiver using a light source as backlight illumination.

  In such an image display device, heat generation due to light emission of the light source may cause problems such as a decrease in light emission efficiency of the light source and variations in luminance and chromaticity. (For example, refer to Patent Document 1 and Patent Document 2).

Japanese Patent Laid-Open No. 11-266036 JP-A-10-31426

  By the way, in recent years, image display devices such as television receivers tend to increase in size, and the number of required light sources such as light emitting diodes tends to increase. Therefore, the amount of heat generated when the light source emits light is increasing, and it is necessary to improve the cooling efficiency more than ever.

  Therefore, it is an object of the present invention to overcome the above-described problems and improve the cooling efficiency.

In order to solve the above-described problem, the illumination device of the present invention has a housing having an arrangement surface portion formed of a heat conductive material, a plurality of light sources arranged on one surface of the arrangement surface portion, and the other of the arrangement surface portions. An air flow space in which a heat dissipating fin disposed at a position facing the plurality of light sources on the surface and a cover that is attached to the housing and closes the heat dissipating fin is provided, and cooling air is caused to flow by the disposing surface portion of the housing and the cover The cover is provided with an intake hole for taking cooling air into the air flow space, and provided with an exhaust fan attached to the outer surface of the cover for discharging the cooling air flowing in the air flow space. the induction member for inducing cooling air taken from the intake holes to the heat radiation fins arranged, the lower end portion of the placement surface of the guide member, and, collected and separated in the right-left between the heat radiation fins It is what you gave.

In order to solve the above-described problem, the image display device of the present invention includes a heat dissipating fin disposed at a position opposite to the plurality of light sources on the surface opposite to the surface on which the plurality of light sources of the disposition surface portion are disposed, and a housing. And a cover that closes the radiating fins is provided, the arrangement surface portion is formed of a heat conductive material, an air flow space is formed by the arrangement surface portion and the cover to flow cooling air, and cooling air is supplied to the cover and the air flow space. An intake fan is formed, and an exhaust fan that discharges the cooling air that is attached to the outer surface of the cover and flows in the air flow space is provided, and the cooling air taken from the intake hole is guided to the heat radiating fin in the air flow space. An induction member is arranged, and the induction member is attached to the lower end portion of the arrangement surface portion and between the heat dissipating fins so as to be separated to the left and right .

Therefore, in the illumination device and the image display device according to the present invention, the cooling air taken into the air flow path from the air intake hole is efficiently guided to the heat radiating fins by the guide member attached to the left and right between the heat radiating fins. Released from the exhaust fan.

The illuminating device of the present invention has a housing having an arrangement surface portion formed of a heat conductive material, a plurality of light sources arranged on one surface of the arrangement surface portion, and the plurality of light sources on the other surface of the arrangement surface portion. And a cover that is attached to the housing and closes the heat radiation fin to form an air flow space for allowing cooling air to flow by the housing placement surface portion and the cover. An air intake hole that takes in the cooling air is formed in the space, and an exhaust fan that discharges the cooling air that is attached to the outer surface of the cover and flows in the air flow space is provided, and the cooling air taken in from the air intake hole is placed in the air flow space. A guide member for guiding to the heat radiating fin is disposed, and the guide member is attached to the lower end portion of the placement surface portion and spaced apart between the heat radiating fins .

Therefore, the absorption rate by the cooling air of the heat | fever transmitted to the radiation fin by the induction | guidance | derivation member spaced apart on either side between the radiation fins is high, and it can aim at the improvement of the cooling efficiency in an illuminating device.

The image display device of the present invention is an image display device in which an image display unit that displays an image is attached to a housing having an arrangement surface portion, and a plurality of light sources that function as a backlight of the image display portion are arranged on one surface of the arrangement surface portion. And a radiation fin disposed at a position opposite to the plurality of light sources on the surface opposite to the surface where the plurality of light sources of the arrangement surface portion is disposed, and a cover attached to the housing and closing the radiation fins. The placement surface part is made of a heat conductive material, the air flow space that allows cooling air to flow is formed by the placement surface part and the cover, the intake hole that takes the cooling air into the air flow space is formed in the cover, and is attached to the outer surface of the cover An exhaust fan that discharges the cooling air that has flowed in the air flowing space is provided, and the cooling air taken from the intake holes is guided to the heat radiating fin in the air flowing space. The member is arranged, the lower end portion of the placement surface of the guide member, and is characterized in that mounted spaced apart on the left and right between the heat radiation fins.

Therefore, the absorption rate by the cooling air of the heat | fever transmitted to the radiation fin by the induction | guidance | derivation member attached spaced apart between the radiation fins right and left is high, and it can aim at the improvement of the cooling efficiency in an image display apparatus.

  The best mode of the illumination device and the image display device of the present invention will be described below with reference to the accompanying drawings.

  In the best mode shown below, the image display device of the present invention is applied to a television receiver that displays an image on a liquid crystal panel, and the illumination device of the present invention is installed in the back of the television receiver. This is applied to a light illumination device.

  The scope of application of the present invention is not limited to a television receiver having a liquid crystal panel and a backlight illuminating device provided therein, and other various television receivers and image display devices used in personal computers. Etc. and various illumination devices used for these.

  The image display device (television receiver) 1 is configured by disposing required parts inside an outer casing 2 (see FIGS. 1 and 2).

  The outer casing 2 is formed in a box shape that is opened forward and backward flat, and an image display unit 3 that displays an image is disposed at a position that closes the opening from the inside. The image display unit 3 is configured, for example, by sandwiching a transmissive color liquid crystal panel between two polarizing plates from the front and the back, and displays a full-color image by being driven by an active matrix system.

  A lighting device 4 is arranged inside the outer casing 2 (see FIG. 2). The illuminating device 4 is configured by arranging necessary parts in a housing 5.

  The housing 5 is formed in a box shape that is opened forward and backward flattened by a metal material having high thermal conductivity and the like, as shown in FIGS. 2 and 3, the arrangement surface portion 6 facing the front-rear direction and the arrangement surface portion. 6 and a peripheral surface portion 7 protruding forward from the outer peripheral edge.

  An optical function sheet 8 and a diffusion plate 9 are attached to the front end of the housing 5 (see FIG. 2).

  The optical function sheet 8 is, for example, a predetermined sheet such as a diffusion sheet that diffuses light emitted from a light source (light emitting diode) described later, a prism sheet that refracts light to guide the light in a predetermined direction, or a polarization conversion sheet that converts the polarization direction. Various sheets having the optical function are laminated in a layered manner.

  The optical function sheet 8 is attached to the front surface of the diffusion plate 9, and the diffusion plate 9 is disposed so as to face the light source. The diffusing plate 9 has a function of diffusing light emitted from the light source inside the housing 5 to achieve uniform luminance in surface light emission.

  On one surface of the arrangement surface portion 6 of the housing 5, that is, the front surface 6 a, for example, light source units 10, 10,. reference). The light source unit 10 is formed by arranging a plurality of light sources 10b, 10b,... As the light sources 10b, 10b,..., For example, a red light emitting diode that emits red light, a green light emitting diode that emits green light, and a blue light emitting diode that emits blue light are used. These light sources 10b, 10b,... Are used as backlights when displaying images in the image display unit 3.

  A holding frame 11 is attached to the front surface of the housing 5 (see FIG. 2). The image display unit 3 is held at the front end of the holding frame 11.

  Radiation fins 12, 12,... Are attached to the other surface of the arrangement surface portion 6 of the housing 5, that is, the rear surface 6b, at equal intervals on the left and right sides (see FIGS. 2 and 4). The heat dissipating fin 12 is integrally formed with a plate-like attached surface portion 12a attached to the arrangement surface portion 6 and facing in the front-rear direction, and heat radiating surface portions 12b, 12b,... Protruding rearward from the attached surface portion 12a. The heat dissipating surface portions 12b, 12b,... Are formed in a plate shape facing in the left-right direction, extend vertically and are provided at equal intervals on the left and right.

  The heat radiating fins 12, 12,... Are disposed at positions facing the light source units 10, 10,..., That is, positions immediately behind the light source units 10, 10, respectively (see FIG. 3).

  Guide members 13, 13,... Are attached to the lower surface of the rear surface 6b of the arrangement surface portion 6 of the housing 5 so as to be spaced apart from each other (see FIG. 4). Are arranged on the left side of the radiating fin 12 located on the left side and the right side of the radiating fin 12 located on the right side.

  The guide member 13 includes a base portion 13a attached to the arrangement surface portion 6 and a partition portion 13b protruding rearward from the upper end portion of the base portion 13a. The upper end of the partition portion 13b and the lower end of the radiating fin 12 are substantially the same height. Is located.

  A cover 14 is attached to the rear surface 6b of the arrangement surface portion 6 of the housing 5 in a state in which the radiation fins 12, 12,... And the guiding members 13, 13,. reference). The cover 14 is made of a metal material having high thermal conductivity, and has a rectangular base surface portion 15 facing in the front-rear direction, and an upper surface portion 16, a lower surface portion 17, and a side surface portion protruding forward from the outer peripheral edge of the base surface portion 15 18 and 18.

  The cover 14 is attached to the arrangement surface portion 6 with the front ends of the upper surface portion 16, the lower surface portion 17 and the side surface portions 18, 18 in contact with the rear surface 6 b. Therefore, an internal space in which the radiation fins 12, 12,... And the guide members 13, 13,. The base surface portion 15 of the cover 14 is in contact with the heat radiation surface portions 12b, 12b, ... of the heat radiation fins 12, 12, ... (see Fig. 5).

  Exhaust holes 15 a, 15 a, 15 a are formed at positions near the upper end of the base surface portion 15 of the cover 14 so as to be separated from each other in the left-right direction.

  A plurality of intake holes 17a, 17a,... Are formed in the lower surface portion 17 of the cover 14 (see FIGS. 5 and 6).

  Exhaust fans 20, 20, 20 are attached to the rear surface of the base surface portion 15 of the cover 14 (see FIGS. 2 and 7). The exhaust fans 20, 20, 20 are attached to the base surface portion 15 so as to close the exhaust holes 15a, 15a, 15a, respectively.

  A circuit board 21 is disposed inside the outer casing 2 behind the lower end of the casing 5 (see FIG. 2). The circuit board 21 is formed with necessary circuits such as a drive circuit for the image display unit 3, a drive circuit for the light source units 10, 10,... And a drive circuit for the exhaust fans 20, 20, 20.

  In the image display device 1 configured as described above, when an image is displayed on the image display unit 3, the light source units 10, 10,... Are driven, and the light sources 10b, 10b,. Emits light. At this time, heat is generated with the light emission of the light sources 10b, 10b,..., And the generated heat is transmitted from the arrangement surface portion 6 of the housing 5 to the radiation fins 12, 12,.

  When the light sources 10b, 10b,... Emit light, cooling air is taken into the air flow space 19 from the intake holes 17a, 17a,. The cooling air is guided to the radiation fins 12, 12,... By the partition portions 13b, 13b,.

  The cooling air induced to the radiation fins 12, 12,... Radiates heat while absorbing heat transmitted to the radiation fins 12, 12,. Ascending along the fins 12, 12,. .

  The raised cooling air is discharged to the outside of the air flow space 19 from the exhaust fans 20, 20, 20 through the exhaust holes 15 a, 15 a,... Formed in the base surface portion 15 of the cover 14.

  As described above, in the image display device 1, the cooling air is guided and flowed to the radiation fins 12, 12,... By the guide members 13, 13,. The temperature rise of the light sources 10b, 10b,... Due to the accompanying heat is suppressed.

  The heat generated by the light emission of the light sources 10b, 10b,... And transferred to the heat radiation fins 12, 12,... Is forced by the cooling air exhaust fans 20, 20, 20 as described above. In addition to being released, it is transmitted to the cover 14 that is in contact with the radiation fins 12, 12,.

  In addition, air flow holes (not shown) are formed in the back surface and the peripheral surface of the outer casing 2, and cooling air is taken into the air flow space 19 from the intake holes 17 a, 17 a,. Further, the cooling air whose temperature has risen due to heat absorption is discharged from the exhaust fans 20, 20, 20 to the outside of the outer casing 2 through the air flow holes.

  As described above, in the image display device 1, the light source 10 b, the guide members 13, 13,... That guide the cooling air to the heat radiation fins 12, 12,. The temperature rise of the light sources 10b, 10b,... Due to heat generated with the light emission of 10b,.

  Therefore, the absorption rate by the cooling air of the heat transmitted to the radiation fins 12, 12,... Is high, and the cooling efficiency can be improved.

  Moreover, since the temperature rise in the housing 5 is suppressed by the cooling air, the luminous efficiency of the light sources 10b, 10b,... Is improved and the temperature distribution between the light sources 10b, 10b,. Therefore, it is possible to prevent the occurrence of problems such as unevenness in luminance and change in color tone due to changes in wavelength.

  Further, in the image display device 1, since the intake holes 17a, 17a,... For taking in the cooling air are formed below the exhaust fans 20, 20, 20, the cooling air is supplied to the radiating fins 12, 12,. ... can be easily flowed along, and the cooling efficiency can be improved.

  Furthermore, in the image display device 1, since the intake holes 17 a, 17 a,... Are formed in the lower surface portion 17 of the cover 14 that forms the air flow space 19, the cooling air is efficiently used in the air flow space 19. The temperature rise of the light sources 10b, 10b,... Can be efficiently suppressed.

  In addition, in the image display device 1, the cover 14 is formed of a heat conductive material, and the cover 14 is brought into contact with the heat radiation surface portions 12b, 12b,... Of the heat radiation fins 12, 12,. Since heat is also radiated from the cover 14, the cooling efficiency can be further improved.

  In the image display device 1, a circuit board 21 having a drive circuit for the image display unit 3 and drive circuits for the light source units 10, 10,. Accordingly, the circuit board 21 generates heat when each circuit is driven, but a heat shield means may be provided between the cover 14 and the circuit board 21 in order to prevent the generated heat from being transmitted to the cover 14. As such a heat shield means, for example, various means such as a heat insulating film or an infrared reflecting sheet attached to the back surface of the cover 14 can be used.

  In the above, an example in which the vertically long light source units 10, 10,... Having the light sources 10b, 10b,. The arrangement of 10b,... Is not limited to such an arrangement, and any arrangement can be used as long as it effectively exhibits the function as a backlight. For example, as shown in FIG. 8, the light source units 10A, 10A,... May be arranged apart from each other vertically and horizontally, and the light sources 10b, 10b,. .

  Further, the number of exhaust fans 20 and intake holes 17a may be arbitrarily arranged or formed in consideration of cooling efficiency, manufacturing cost, and the like, and the arrangement position or formation position can be arbitrarily set. . For example, it is possible to dispose the exhaust fan 20 below the intake hole 17a and allow the cooling air to flow downward from above, and depending on the arrangement position or formation position of the exhaust fan 20 and the intake hole 17a, cooling can be performed. It is also possible to adopt a configuration in which air flows in the left-right direction or the oblique direction.

  Furthermore, as shown in FIG. 9, for example, a cover 14B in which the air flow space is divided into two upper and lower stages is attached to the housing 5, and the exhaust fans 20 and 20 are respectively attached to the upper part and the lower part of the cover 14B. ,... Can be arranged.

  The specific shapes and structures of the respective parts shown in the above-described best mode are merely examples of the implementation of the present invention, and the technical scope of the present invention is limited by these. It should not be interpreted in a general way.

FIG. 2 to FIG. 9 show the best mode for carrying out the present invention, and this figure is a schematic perspective view showing an image display device. It is a longitudinal cross-sectional view of an image display apparatus. It is a front view which shows a housing | casing and the light source unit arrange | positioned at this. It is a rear view which shows a housing | casing, and the radiation fin and induction member attached to this. It is an expanded sectional view of the principal part. It is a bottom view of a cover. It is a rear view of the cover shown with an exhaust fan. It is a front view which shows the example in which the light source unit was arranged up and down, right and left. It is a rear view which shows the example in which the cover in which an air flow space is divided up and down is provided.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Image display apparatus, 3 ... Image display part, 4 ... Illuminating device, 5 ... Housing | casing, 6 ... Arrangement | positioning surface part, 10b ... Light source, 12 ... Radiation fin, 13 ... Induction member, 13a ... Base part, 13b ... Partition part, DESCRIPTION OF SYMBOLS 14 ... Cover, 17 ... Lower surface part, 17a ... Intake hole, 19 ... Air flow space, 20 ... Exhaust fan, 14B ... Cover

Claims (6)

A housing having an arrangement surface portion formed of a thermally conductive material;
A plurality of light sources arranged on one surface of the arrangement surface portion;
Radiation fins arranged at positions facing the plurality of light sources on the other surface of the arrangement surface portion;
A cover that is attached to the housing and closes the heat dissipating fins;
An air flow space for flowing cooling air is formed by the arrangement surface portion of the housing and the cover,
In the cover, an air intake hole that takes cooling air into the air flow space is formed,
An exhaust fan that exhausts the cooling air that is attached to the outer surface of the cover and flows in the air flow space is provided.
In the air flow space, a guide member that guides the cooling air taken from the intake holes to the heat radiating fins is arranged ,
An illumination device, wherein the guide member is attached to a lower end portion of the arrangement surface portion and spaced apart between the heat dissipating fins . The lighting device according to claim 1, wherein the intake hole is formed below the exhaust fan. The cover is formed in a box shape opened on the arrangement surface side of the housing,
The lighting device according to claim 2, wherein the suction hole is formed in a lower surface portion of the cover. The cover is formed of a heat conductive material,
The lighting device according to claim 1, wherein the cover is in contact with the radiating fin. The induction member includes a base portion attached to the arrangement surface portion and a partition portion protruding backward from the upper end portion of the base portion, and the upper end of the partition portion and the lower end of the radiating fin are positioned at substantially the same height. ing
The lighting device according to claim 1. An image display device in which an image display unit that displays an image is attached to a housing having an arrangement surface unit, and a plurality of light sources that function as a backlight of the image display unit are arranged on one surface of the arrangement surface unit,
A heat dissipating fin disposed at a position opposite to the plurality of light sources on the surface opposite to the surface on which the plurality of light sources of the arrangement surface portion are disposed;
A cover that is attached to the housing and closes the heat dissipating fins;
The placement surface part is formed of a heat conductive material,
An air flow space for flowing cooling air is formed by the arrangement surface portion and the cover,
In the cover, an air intake hole that takes cooling air into the air flow space is formed,
An exhaust fan that exhausts the cooling air that is attached to the outer surface of the cover and flows in the air flow space is provided.
In the air flow space, a guide member that guides the cooling air taken from the intake holes to the heat radiating fins is arranged ,
An image display device, wherein the guide member is attached to a lower end portion of the arrangement surface portion and between the heat dissipating fins so as to be separated from each other on the left and right .

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