JP2010002882A - Display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device capable of effectively dissipating the heat generated in a plasma display panel, even when air cannot be fully convected. <P>SOLUTION: The display device 1 includes a plasma display panel 10 comprising two glass substrates 11, 12 laminated to each other; a chassis 30 disposed in the back face 10a side of the plasma display panel 10; and a back cover 40 disposed in the back face 30a side of the chassis 30, wherein the chassis 30 has an emissivity of ≥0.5 on the surface 30a opposing to the back cover 40, giving a gap X of ≤20 mm from the back cover 40. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention includes a plasma display panel formed by bonding two glass substrates, a chassis disposed on the back side of the plasma display panel, and a back cover disposed on the back side of the chassis. The present invention relates to a display device, and more particularly, to a display device that can efficiently dissipate heat even in a situation where airflow between the chassis and the back cover is hindered due to a reduction in thickness.

  A display device used for a plasma television or the like generally includes a plasma display panel and a back cover disposed on the back surface thereof.

  In such a display device, the plasma display panel generates heat together with light, and this heat accumulates in the display device, resulting in a short life of a circuit or the like and deterioration of each member and contact due to thermal stress. was there. Furthermore, as the current plasma displays are becoming thinner, larger, and brighter, the heat generated from the plasma display panel is increasing. Therefore, measures against this heat generation are considered to be very important. ing.

  As countermeasures for the above heat generation, conventionally, heat generated from the plasma display panel is conducted to the chassis located on the back side thereof, and forced convection using air or a fan is used on the back side of the heated chassis. A display device that dissipates heat by convection is exemplified. For example, as disclosed in Patent Document 1, by optimizing the material of the heat conductive sheet located on the back side of the plasma display panel, the plasma display panel and the heat conductive sheet can be easily brought into close contact with each other. As a result, heat can be transferred uniformly to the chassis located on the back side of the display device, so that there is a display device that can efficiently dissipate heat by the thermal convection of the chassis.

  However, although the display device of Patent Document 1 has a certain heat dissipation effect, when it is adopted in a television that is currently increased in size and thickness, a path for air to convection becomes longer due to the increase in size, Since the gap between the chassis and the back cover located on the back surface of the chassis is narrowed, there is a problem that it is difficult to obtain a sufficient heat radiation effect due to difficulty in heat convection of the conventional chassis.

Japanese Patent No. 3499848

  An object of the present invention is to provide a display device that can effectively dissipate heat generated in a plasma display panel even when sufficient air convection cannot be achieved by optimizing the chassis and the back cover. It is to provide.

  As a result of diligent research to solve the above problems, the inventors of the present invention have a conventional chassis with a metal surface. When the distance from the back cover is 20 mm or less, convection is hindered. Compared to the case, the chassis temperature rises, but by setting the emissivity of the surface of the chassis facing the back cover to 0.5 or more, the heat generated by the chassis is added to the conventional heat dissipation by convection. Since the heat can be transferred to the back cover as infrared rays to dissipate heat, effective heat dissipation can be achieved even when the space between the back cover and the back cover is narrow and sufficient air convection is not possible. It was.

The present invention has been made based on such findings, and the gist thereof is as follows.
(1) A display comprising a plasma display panel formed by bonding two glass substrates, a chassis disposed on the back side of the plasma display panel, and a back cover disposed on the back side of the chassis. The display device according to claim 1, wherein the chassis has an emissivity of a surface facing the back cover of 0.5 or more, and a distance from the back cover of 20 mm or less.

(2) The display device according to (1), wherein the chassis is a surface-treated metal plate formed by forming a film having the emissivity on at least a surface facing the back cover.

(3) the _{coating, SiO 2, ZrO 2, TiO} 2, Al 2 O 3, Fe 2 O 3, Al 2 Si 4 O 10 (OH) 2, muscovite, fluorite, talc, of SiC and carbon black The display device according to (2), wherein the display device is a coating film including at least one of them.

(4) The display device according to (2), wherein the film is a composite layer formed by sequentially forming a blackened electric Zn-Ni plating layer and an organic resin film.

(5) The display device according to any one of (1) to (4), wherein the back cover has an emissivity of a surface facing the chassis of 0.5 or more.

  ADVANTAGE OF THE INVENTION According to this invention, even if it is a case where sufficient air convection cannot be performed, it became possible to provide the display apparatus which can thermally radiate the heat | fever which generate | occur | produced in the plasma display panel effectively.

It is the disassembled perspective view which showed the principal part of the display apparatus by this invention typically. FIG. 3 is an exploded cross-sectional view schematically showing a main part of the display device according to the present invention.

Hereinafter, the configuration of the present invention and the reasons for limitation will be described with reference to the drawings.
FIG. 1 is an exploded perspective view schematically showing main parts of a display device according to the present invention, and FIG. 2 is an exploded cross-sectional view schematically showing main parts of the display device according to the present invention.

  1 and 2, the display device according to the present invention includes a plasma display panel 10, a chassis 30 disposed on the back surface 10a side of the plasma display panel 10, and a back surface 30a side of the chassis. The display device 1 includes a back cover 40 that has been made. In the present invention, for the front and back of the chassis 30 and the back cover 40, the plasma display panel side is referred to as b-plane and the opposite side is referred to as a-plane.

In the display device 1 according to the present invention, the chassis 30 has an emissivity of the surface 30a facing the back cover 40 of 0.5 or more, and an interval X between the chassis 30 and the back cover 40 is 20 mm or less. Features. By adopting such a configuration, after the heat generated from the plasma display panel 10 is conducted to the chassis 30, in addition to heat radiation by conventional convection, the heat radiated from the surface 30 a is converted into infrared rays as the back cover 40. As a result of heat conduction to the back cover 40 and heat dissipation, the space X between the chassis 30 and the back cover 40 is narrow, and effective heat dissipation is possible even when air convection is not sufficient. Become.
Here, the interval X refers to a minimum interval where the chassis 30 of the display device 1 and the back cover 40 are in contact with each other through the atmosphere. For example, as shown in FIGS. 1 and 2, Arbitrary at least one line P1, P2 extending in the stacking direction of the members 10 to 50 of the display device 1 is moved in a direction C perpendicular to the longitudinal direction L of the plasma display panel, and the chassis 30 at each point. And the back cover 40 are measured, and the minimum value among them can be determined as the distance X. 1 and 2 are both exploded views, and for convenience, the position of the interval X is shown.

The reason why the emissivity of the surface 30a of the chassis 30 facing the back cover 40 is 0.5 or more depends on the temperature of the chassis 30 and the emissivity of the back cover 40, but on the surface where the emissivity is less than 0.5. This is because a heat dissipation effect of about 3 ° C or higher is recognized. In general, when the amount of radiant heat transfer per unit area radiated from the surface A is not reflected from the atmosphere,
W (unit _{area) = σ × ε A × (} T A 4 -T X 4)
σ: Stefan Boltzmann constant, ε _A : emissivity of surface A, T _A : surface A temperature (K), T _X : ambient temperature (K)
It is represented by Therefore, it can be seen that if (T _A ⁴ −T _X ⁴ ) is the same, the greater the emissivity ε _A radiates more heat.

  The distance X is limited to 20 mm or less in a region where heat dissipation by conventional convection or forced convection cannot be expected, and the surface 30a of the chassis 30 facing the back cover 40 has an emissivity of 0.5 or more. This is because a remarkable heat dissipation effect can be obtained. The surface where the emissivity of the present invention is 0.5 or more may be the entire surface 30a facing the back cover 40 of the chassis 30 or only the surface where the distance X is 20 mm or less. Moreover, it is good also as a full width part of C direction including the part from which the said space | interval X becomes 20 mm or less (the width | variety of L direction is arbitrary). Further, as will be described later, a circuit board (not shown) is formed on the surface 30a facing the back cover of the chassis 30. The surface of the circuit board portion has an emissivity of 0.5 or more. There is no need. This is because it is difficult to adjust the emissivity of the circuit portion, and if the surface portion 30a on which the circuit board is not formed has an emissivity of 0.5 or more, a sufficient heat dissipation effect can be obtained as the entire display device. .

Below, the detail about each member which comprises the display apparatus 1 of this invention is described.
The configuration of the plasma display panel 10 of the present invention is a member formed by bonding two glass substrates (a front plate 11 and a rear plate 12) as shown in FIGS. 1 and 2, and a display using gas discharge. It is a member for performing. The configuration is not particularly limited in the present invention. For example, elongated electrodes (address electrodes) are arranged in the vertical direction, and red, green, and blue phosphors that are the three primary colors of light are applied thereon. A commonly used plasma display panel may be used in which the rear plate 12 and the front plate 11 in which electrode pairs are arranged in the horizontal direction on the glass surface are bonded together and a rare gas is sealed therebetween.

  In addition, as shown in FIG. 2, the display device 1 of the present invention preferably further includes a cover glass 50 on the front surface 10 b side of the plasma display panel 10. The cover glass 50 is a member for fulfilling the role of protecting the plasma display panel and the like, and is a light-transmitting material. If the cover glass 50 can fulfill the above-mentioned role, the cover glass 50 is not limited to glass, and plastic or the like can be used. It is.

  Furthermore, as shown in FIG. 2, the display device 1 of the present invention preferably further includes a heat transfer sheet 20 on the back surface 10 a side of the plasma display panel 10. The heat transfer sheet 20 is a member that serves to efficiently transfer the heat generated from the plasma display panel 10 to the chassis 30. The configuration is not particularly limited as long as heat can be transferred efficiently, and for example, a silicon resin or a urethane foam resin can be used, and the shape thereof is a single plate shape as shown in FIG. A thing can be used, or a plurality of plate-like pieces can be collected and formed.

  As shown in FIGS. 1 and 2, the chassis 30 of the present invention is provided on the back surface 10a side of the plasma display panel 10 (in the figure, the back surface 20a side of the heat transfer sheet 20), and the plasma display panel 10 is disposed on the back surface side. It is a member that is held from the outside, and also serves to absorb heat generated from the plasma display panel 10 and release it to the outside. A plurality of circuit boards (not shown) are provided on the rear surface 30a side of the chassis 30 to drive and control the light emission of the plasma display panel 10. Further, the chassis 30 is made of a material having a high thermal conductivity so that heat generated from the plasma display panel 10 can be absorbed, and an emissivity of the surface 30a facing the back cover 40 being 0.5 or more. Although a specific material is not specifically limited, For example, although an aluminum plate, a steel plate, a copper plate, etc. can be used, it is preferable to use the steel plate excellent in balance of rigidity, workability, mass, and cost.

  The chassis 30 is preferably a surface-treated metal plate formed by forming a film having the emissivity on at least the surface 30a facing the back cover 40. If the film is formed, a metal plate (aluminum plate, steel plate, copper plate, etc.) used in a normal chassis can be used, and a desired emissivity can be obtained relatively easily only by forming the film. Because it can. Furthermore, although the said metal plate secures the outstanding workability and corrosion resistance, the kind of plating is not limited, It is more suitable to use a plated steel plate.

The coating is composed of SiO ₂ , ZrO ₂ , TiO ₂ , Al ₂ O ₃ , Fe ₂ O ₃ , Al ₂ Si ₄ O ₁₀ (OH) ₂ , muscovite, fluorite, talc (Mg ₃ Si ₄ O ₁₀ A coating film containing at least one of (OH) ₂ ), SiC and carbon black is preferable. This is because if the coating film containing the above components is formed on the metal plate, the required emissivity of 0.5 or more can be obtained.
Moreover, it is preferable that the sum total of content of each said component in the said coating film shall be 10 mass% or more. This is because a higher emissivity can be obtained if the content is 10% by mass or more. The upper limit of the total content is not particularly limited and is not limited as long as it does not cause defects that cause problems in design and rust prevention. For example, it may be a composition made of an inorganic material such that (SiO ₂ ) _n is 100%.
Further, the film thickness is preferably 2 to 20 μm. If it is 2 μm or more, it is possible to improve the emissivity of the back surface 30a of the chassis 30 formed with a coating on a metal surface having an emissivity of less than 0.1 to 0.5 or more. This is because a desired emissivity can be secured without using a film and the workability of the chassis is not affected.

Moreover, it is preferable that the said film | membrane is a composite layer which formed the electric Zn-Ni plating layer and organic resin film | membrane which were blackened in order. This is because if the composite layer is formed on the metal plate, an emissivity of 0.5 or more can be obtained as in the case where the coating film is formed. Examples of the composite layer include a composite layer in which an organic resin layer such as an acrylic resin or a polyester resin is formed on a blackened electric Zn-Ni plating layer.
The film thickness of the composite layer is preferably 1 to 5 μm. This is because if the thickness is 1 μm or more, the emissivity of the back surface 30a of the chassis 30 can be 0.5 or more, and if it is 5 μm or less, a desired emissivity can be secured without uselessly forming a thick film.

  As shown in FIGS. 1 and 2, the back cover 40 of the present invention is disposed on the rear surface 30a side of the chassis 30 and covers the plasma display panel 10 and the chassis 30 of the display device 1 of the present invention from the outside. It is a member for protection.

  The back cover 40 is mainly made of a pre-coated steel plate. The pre-coated steel sheet preferably forms a coating film with excellent scratch resistance in order to prevent the coating film from rubbing by being hit with a mold during press working and preventing deterioration of the design feeling. In addition, in order to prevent leakage of electromagnetic waves, at least the surface 40b on the chassis 30 side is made conductive so that the junction of the back cover 40 can be made conductive and electromagnetic waves generated from internal electronic devices can be blocked. It is preferable to form an excellent chemical conversion coating.

The back cover 40 preferably has an emissivity of a surface 40b facing the chassis 30 of 0.5 or more. This is because the infrared rays radiated from the chassis 30 can be more effectively absorbed by increasing the emissivity (ε _B ) of the surface 40 _b facing the chassis 30. Furthermore, a more preferable emissivity is 0.8 or more.
In addition, in order to obtain the emissivity, as in the case of the chassis 30, a coating film for improving the emissivity is formed on the surface of the electroplated Zn-Ni plated layer or blackened. A composite layer having an organic resin layer such as an acrylic resin or a polyester resin may be formed thereon.

  The above description is merely an example of the embodiment of the present invention, and various modifications can be made within the scope of the claims.

Examples of the present invention will be described.
(Examples 1-8, Comparative Examples 1-4, Reference Example)
As Examples 1 to 8, Comparative Examples 1 to 4 and Reference Examples, as shown in FIG. 2, from two glass substrates having a thickness of 1.8 mm in which a cover glass 50 having a thickness of 2.7 mm is formed on the surface side 10b A plasma display panel 10 and a heat transfer sheet 20 having a thermal conductivity of 0.6 W / m · K and a thickness of 0.8 mm made of foamed acrylic rubber disposed on the back surface 10 a side of the plasma display panel 10. The display device 1 including the chassis 30 disposed on the back surface 20a side of the heat transfer sheet 20 and the back cover 40 disposed on the back surface 30a side of the chassis 30 was produced. The type of metal plate on the entire surface 30a of the chassis 30 facing the back cover 40, the type / amount of coating (g / m ² ), the presence / absence / type / film thickness (μm) and emissivity of the coating. Table 1 shows the type and emissivity of the entire surface 60b of the back cover 40 facing the chassis 30. In addition, A1 and A2 and B1 and B2 are respectively the same in the kind / attachment amount of the plating layer and the kind / film thickness of the film.
The interval X was measured at the center of the chassis 30 (intersection of diagonal lines connecting the corners of the chassis 30). In addition, about the emissivity, the spectral emissivity was measured and it calculated by the integrated intensity of the measurement wavelength range. The measurement conditions are shown below.
Instrument strength: JIR-E far infrared spectroradiometer JIR-E500, measurement temperature: 100 ° C., measurement wavelength: 4.5 to 25 μm, resolution: 8 cm ⁻¹ , integration count: 100 times, other conditions: JIS R1801: Compliant with 2002

  The display device obtained as described above was evaluated. The evaluation method is shown below.

(Evaluation methods)
The display device obtained in each example and each comparative example was used as a 42V type plasma display (340W), and the white space was continuously lit for 30 minutes, and then the interval X was measured (center portion of the chassis 30). A thermocouple was attached to the surface 30a of the chassis 30 facing the back cover 40, and the temperature (° C.) was measured.
The measured temperature was evaluated according to the following evaluation criteria, and the measurement results and evaluation results are shown in Table 1.
: Less than 55 ° C
○: 55 ℃ or more, less than 60 ℃
×: 60 ° C or higher

  According to Table 1, it turns out that the display apparatus of Examples 1-8 has the outstanding heat dissipation compared with Comparative Examples 1-4. Further, although the reference example has the same heat dissipation as that of the fourth embodiment, it is considered that the heat dissipation effect by convection is exhibited because the distance between the chassis and the back cover is as large as 30 mm.

  ADVANTAGE OF THE INVENTION According to this invention, even if it is a case where sufficient air convection cannot be performed, it is possible to provide the display apparatus which can thermally radiate the heat | fever which generate | occur | produced in the plasma display panel effectively.

DESCRIPTION OF SYMBOLS 1 Display apparatus 10 Plasma display panel 20 Heat-transfer sheet | seat 30 Chassis 40 Back cover 50 Cover glass X Distance P1, P2 line of a chassis and a back cover

Claims (5)

In a display device comprising a plasma display panel formed by laminating two glass substrates, a chassis disposed on the back side of the plasma display panel, and a back cover disposed on the back side of the chassis,
The display device, wherein the chassis has an emissivity of a surface facing the back cover of 0.5 or more, and a distance from the back cover of 20 mm or less.   The display device according to claim 1, wherein the chassis is a surface-treated metal plate formed by forming a film having the emissivity on at least a surface facing the back cover. The _{coating, SiO 2, ZrO 2, TiO} 2, Al 2 O 3, Fe 2 O 3, Al 2 Si 4 O 10 (OH) 2, muscovite, fluorite, talc, at least one of SiC and carbon black The display device according to claim 2, wherein the display device is a coating film including one.   3. The display device according to claim 2, wherein the coating is a composite layer formed by sequentially forming a blackened electric Zn-Ni plating layer and an organic resin coating.   The display device according to claim 1, wherein an emissivity of a surface of the back cover facing the chassis is 0.5 or more.

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