JPS6255837A - Projection type cathode-ray tube - Google Patents

Abstract

PURPOSE:To increase furthermore the cooing effect of a fluorescent screen panel by a coolant, by contacting and furnishing a good thermal conductive metallic member at the surface contacting to the setting position of a radiator plate. CONSTITUTION:At the front surface 7c side of a radiator plate 7 contacting to a setting position 12, is arranged a good thermal conductive metallic member 13 contacting and laminating numerous sheets of aluminum foil, for example, of a good thermal conductivity and a low hardness. Since the good thermal conductive metallic member 13 has little rigidity and a relatively good flexibility, it is suitable to place between the front surface 7c of the radiator plate 7 and the setting position 12, produces no distortion when installed, and reduces the thermal resistance by contacting closely. Therefore, the heat of the radiator plate 7 is partially transmitted and displaced to the setting position 12 through the good thermal conductive metallic member 13, resulting in an improvement of the thermal radiation effect.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a liquid-cooled projection cathode ray tube used in color projectors and the like.

[Background of the invention]

Generally, in a color projector using a cathode ray tube system, images of each color are obtained using a plurality of monochromatic cathode ray tubes, such as a two-tube or three-tube type, and these images are projected onto a projection screen, and each pixel is synthesized on this screen. I am trying to get a colored image.

It is preferable to use a high-intensity cathode ray tube for such a glodictor, but since the high-intensity cathode ray tube has a high output, the temperature of the front panel increases as the tube is operated for a long time, causing the projection screen to rise. There is a problem that the white balance of the projected color image becomes out of order.

One solution to this problem is to create a sealed chamber in which liquid is sealed in contact with the front surface of the fluorescent surface panel of the cathode ray tube, and to use convection of this liquid to diffuse heat through a heat sink installed around the sealed chamber. has been proposed (1977-4)
3926, Japanese Utility Model Application Publication No. 177256/1983).

FIG. 2 is a sectional view showing the structure of such a liquid-cooled high-brightness cathode ray tube. In the figure, fluorescent surface panel section 1.
A funnel part 2 and a neck part 3 constitute a pulp 4, and a fluorescent surface 6 is formed on the inner surface facing an electron gun 5 enclosed within the neck part 3. On the other hand, a frame-shaped heat dissipation plate 7 is adhered to the outer circumferential portion of the fluorescent panel portion 1 via an adhesive 8, and a heat dissipation plate T and a transparent panel 9 are further adhered via an adhesive 8. Although not shown, the heat dissipation plate 1 is provided with an inlet to inject the sufficiently degassed refrigerant liquid 10 into the sealed chamber 11 formed by the fluorescent panel section 1 and the transparent panel 9. Inject it until it has completely drained, and then close it completely with a stopper. As a result, the heat generated from the fluorescent panel section 1 of the bulb 4 due to the convection of the refrigerant liquid 10 in the sealed chamber 11 is not dissipated to the outside through the heat sink T. The surface temperature is suppressed to about 80° C., making it possible to obtain stable images.

In such a system, the operation of a cathode ray tube.

The refrigerant liquid 10 in the sealed chamber 11 repeatedly expands and contracts depending on the temperature during non-operation. Therefore, the temperature of the refrigerant liquid 10 to be injected differs depending on whether it is adjusted for operation or non-operation, but if it is adjusted for operation, the refrigerant liquid 10 contracts when it is not operating, and if it is adjusted for non-operation, it expands during operation. Also, the inside of the sealed chamber 11 is subjected to repeated stress. If this stress exceeds the strength of the bonded surface of the adhesive 8 constituting the sealed chamber 11, an accident will occur in which the adhesive 8 peels off and the refrigerant liquid 10 leaks. Therefore, as the adhesive 8, an organic adhesive such as a silicone-based adhesive with excellent elasticity is used in order to absorb even some of these stresses, so that it can be used for a long period of time due to the rise in temperature. The volumetric expansion of the refrigerant liquid 1o can be absorbed, and a liquid cooling structure can be achieved with a relatively simple configuration.

However, in the structure of such a conventional heat sink 7,
As shown in the figure, the contact area with the refrigerant liquid 1G is limited to the frame-shaped inner end 7a, and heat transfer occurs only through this narrow area.
Since heat was dissipated only in b, the overall heat dissipation effect obtained was still insufficient.

[Purpose of the invention]

The present invention was developed in view of these circumstances.
The purpose of this invention is to provide a projection type cathode ray tube in which the cooling effect of the fluorescent surface panel section by the refrigerant liquid is further enhanced.

[Summary of the invention]

In order to achieve such an object, the present invention has a metal member with good heat conductivity placed in contact with the surface of the heat dissipation plate that comes into contact with the set attachment portion.

[Embodiments of the invention]

Next, embodiments of the present invention will be described in detail using the drawings.

FIG. 1 shows an embodiment of a projection type cathode ray tube according to the present invention. FIG. 1(a) is a cross-sectional view, and FIG. 1(b) is a plan view thereof. It is. In the same figure, the front surface T that comes into contact with the set attachment part 12 of the heat sink T
On the C side, a material with good thermal conductivity and low hardness, such as At
A metal member 13 with good thermal conductivity, which is made by laminating a large number of foils bonded together, is provided.

Incidentally, reference numeral 14 denotes a mounting hole drilled in the heat dissipation plate 7 for fixing the pulp 4 to the aforementioned set mounting portion 12.

The projection type cathode ray tube configured in this manner is fixedly arranged in the set mounting portion 12 by inserting screws (not shown) into the mounting holes 14 formed in the heat sink T. In this case, since a metal member 13 with good heat conductivity is sandwiched between the front surface 7C of the heat sink 7 and the set mounting portion 12 in surface contact with each other, a part of the heat of the heat sink 7 is transferred to the metal member with good heat conductivity. The heat is conducted to the set mounting portion 12 via the member 13 and is dissipated), thereby improving the heat dissipation effect. In addition, the metal member 13 with good heat conductivity
Since it is constructed by laminating a large number of At foils, it has high rigidity and a certain degree of elasticity, so it can easily fit between the front surface 7c of the heat sink T and the set mounting part 12. ,
Thermal resistance can be reduced because they are placed closely together without causing distortion during installation. Therefore, it is more advantageous to laminate a large number of thin At foils instead of using a single thick foil.

In the above-mentioned embodiment, the metal member 1 with good heat conductivity is used.
3 is provided within the contact surface of the heat dissipation plate surface 7C, but the present invention is not limited to this. By arranging them in wide contact, it is possible to further reduce the thermal resistance and further improve the heat dissipation effect. Moreover, although the case where A4 foil was used as the good thermally conductive metal member 13 was described, it is not limited to At foil, and is not particularly limited as long as it is a metal foil with low hardness and good thermal conductivity.

〔Effect of the invention〕

As explained above, according to the present invention, the heat dissipation effect of the heat sink can be improved by arranging the metal member with good heat conductivity on the surface of the heat sink that comes into contact with the set attachment part, so that the heat dissipation effect of the heat sink can be improved. It is possible to lower the temperature of the light panel, reduce the decrease in brightness of the phosphor, and prevent the occurrence of panel cracks, resulting in a highly reliable glodiector with a bright screen.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of a liquid-cooled projection type cathode ray tube according to the present invention, and FIG. 2 is a sectional view showing a conventional liquid-cooled projection type cathode ray tube. 1... Fluorescent surface panel, 2... Funnel part, 3
... Neck part, 4 ... Bulb, 5 ... Electron gun, 6 ... Fluorescent surface, 7 ... Heat sink, 7 m ...
-Inner end, 7b... Outer end, 7c...front, 8...adhesive, 9...
...transparent panel, 10...refrigerant liquid, 11.fist...
Sealed chamber, 12...Set mounting portion, 13...Good heat conductive metal member, 14...Mounting hole. 5.-□′・ Agent: Patent attorney Ogawasuji i/′. Figure 1Figure 1(b)

Claims (1)

[Claims] A transparent panel is placed in front of the fluorescent panel, the peripheral edges of both panels are fixed with adhesive through a frame-shaped heat sink, and a transparent liquid refrigerant is placed in a sealed chamber surrounded by both panels and the heat sink. 1. A liquid-cooled projection type cathode ray tube formed by sealing a liquid-cooled cathode ray tube, characterized in that a metal member with good thermal conductivity is disposed in contact with a surface of the heat dissipation plate that comes into contact with a set mounting portion.