JPH10312761A - Cathode-ray tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cathode ray tube with improved safety property of the cathode-ray tube including a funnel part at the time when a bulb of the cathode-ray tube is broken. SOLUTION: In this cathode-ray tube 1, a cathode-ray tube is produced by sealing a panel 2 made of glass and a funnel 3 with frits. A HS band 4 is coiled on the skirt part of the panel 2 and a film 6 for explosion prevention is stuck to the outer surface of the funnel 3. Due to the film 6, fragments of the funnel 3 at the time when the cathode-ray tube bulb is broken are prevented from being scattered to the outside of the bulb.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cathode ray tube (CRT) for use in, for example, a television receiver or a computer monitor, and more particularly, an explosion-proof film or the like is formed on a panel surface of the cathode ray tube. It relates to improvement of a cathode ray tube.

[0002]

2. Description of the Related Art In recent years, with the development of electronic technology and the increasing needs of users, efforts have been made to increase the size of television receivers and make them flat panels. In a cathode ray tube corresponding to an increase in the size of a television receiver or a flat panel, it is important to improve the bulb strength while suppressing the weight of the cathode ray tube. In recent years, with the advance of computer simulation technology, practical strength analysis has become possible, and the design method based on the results of this strength analysis has enabled the improvement of the bulb strength of large or flat panel cathode ray tubes. Have been.

However, in such a large or flat panel cathode ray tube, the thickness of the panel glass is increased in comparison with the conventional cathode ray tube in order to secure the strength of the cathode ray tube bulb, so that an increase in weight is avoided. Absent. Here, when the thickness of the panel glass is reduced to reduce the weight of the cathode ray tube, there is a problem that the strength of the cathode ray tube bulb is reduced and the explosion-proof performance is reduced. Accordingly, a method of attaching an explosion-proof film for preventing glass scattering to panel glass of a cathode ray tube has been proposed and partially implemented.

Referring to FIGS. 1 and 2, the structure of a cathode ray tube according to the present invention will be described. 1A and 1B are diagrams showing the outer shape of a cathode ray tube, wherein FIG. 1A is a top view of the cathode ray tube, FIG. 1B is a front view of the cathode ray tube, and FIG. 1C is a rear view of the cathode ray tube.
FIG. 2 is a front view for explaining a safety standard test of the cathode ray tube.

A cathode ray tube 1 shown in FIG. 1 forms a cathode ray tube bulb by frit sealing a panel 2 and a funnel 3 which are glass. Since the inside of the cathode ray tube 1 is under a high vacuum, the atmospheric pressure is always applied to the cathode ray tube bulb, and a high stress is partially generated in the bulb. Therefore, when an impact or damage is applied to the cathode ray tube bulb, the cathode ray tube bulb may explode and glass fragments may be scattered forward.

[0006] On the other hand, safety standards are defined in each country, but the basic requirements of the safety standards are that they do not explode when a certain impact is applied, and that glass shards are generated even if the bulb is broken. Do not fly forward. Specific examples of the safety standards applied to the former are 5.
There is a 5J ball impact test, and a 7J ball impact test in US standards. The latter domestic standard applies a thermal shock test, and the US standard applies a 20J missile test.

In order to satisfy these safety standards, the outer peripheral portion (skirt portion) of the panel 2 of the cathode ray tube 1 is formed as shown in FIG.
Explosion-proof band by shrink fitting as shown in (in the figure, "H
4), and the HS band 4 tightens the skirt portion of the cathode ray tube 1 to reduce vacuum deformation and stress applied to the outer surface of the glass.

As described above, in the cathode ray tube 1 having a large size or a flat panel, an explosion-proof method using a film in combination with the HS band 4 is particularly employed in the cathode ray tube 1 having a flat panel. This method
As shown in FIG. 1B, an explosion-proof film 6 is adhered to the panel 2 or the panel face 5 of the cathode ray tube 1 to prevent damage and absorb shock. As a material of the film 6, for example, a thickness of 100 to 250 μm
PET (polyethylene terephthalate) film
A layer to which a pressure-sensitive adhesive layer of 20 to 50 μm (details will be described later) is added is used.

This method is very effective in terms of absorbing the impact on the panel 2, and can reduce the impact impact force on the cathode ray tube 1 to 1/3 or less. Therefore, the margin for the ball impact test can be greatly improved.

However, UL (American Insurance Association) 20
In the J missile test, as shown in FIG. 2, an X-cut 7 is applied to the film 6 or a scratch 8 is applied to the film or glass to perform a test. In such a case, the film 6 is drawn into the bulb together with the panel glass, and collides with the funnel glass inside the bulb (although the panel glass with the film 6 remains in the bulb), the small broken funnel glass scatters far away. There is a possibility that the safety standard may be deviated. As described above, the film 6 attached to the panel face 5 can greatly reduce glass scattering when the cathode ray tube bulb is broken, but may not satisfy safety standards due to scattering of the broken funnel glass. There is.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to provide a cathode ray tube in which the safety of a cathode ray tube including a funnel portion at the time of breakdown of a cathode ray tube bulb is improved. That is.

[0012]

In order to solve the above problems, a cathode ray tube according to the present invention has a functional film for preventing glass scattering when a cathode ray tube bulb is broken on an outer surface of a cathode ray tube funnel. It is characterized by being formed.
In this way, when the cathode ray tube bulb is broken, the funnel portion is sucked into the bulb inner surface while being attached to the film and can be stopped at the bulb inner surface. be able to. As a result, it is possible to increase the size of the cathode ray tube glass by reducing the thickness thereof or to reduce the weight of the flat panel cathode ray tube.

Preferably, the functional film is formed by laminating a conductive member on at least a part thereof, and the conductive member also serves as an electric / magnetic shield of a cathode ray tube funnel portion. Thereby, the function as a smoothing capacitor can be added to the functional film.

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings.

The details of the cathode ray tube of the present invention will be described with reference to FIGS. FIG. 3 is a cross-sectional view showing an example of the explosion-proof film used for the cathode ray tube of the present invention. In the following description, the external view of the cathode ray tube described with reference to FIG. 1 is used as it is, and the description of overlapping parts is partially omitted.

A cathode ray tube 1 according to the present invention as shown in FIG.
Forms a cathode ray tube bulb by frit sealing the glass panel 2 and the funnel 3. An HS band 4 is wound around the skirt portion of the panel 2, and a feature of the present invention is that an explosion-proof film 6 identical to the film 6 attached to the panel 2 is provided on the outer surface of the funnel 3 of the cathode ray tube 1. Is affixed.

That is, in the cathode ray tube 1 of the present invention, an explosion-proof film 6 similar to the panel 2 is attached to a portion of the funnel 3 other than the anode button 9 and the neck 10 in order to prevent the funnel glass from scattering as described above. Is being worn. Thus, when the cathode ray tube bulb is broken, the funnel 3
Is sucked into the inner surface of the valve while most of it adheres to the film 6, and can be stopped at the inner surface of the valve. Even if the funnel 3 is released to the outside of the valve, the funnel 3 is adhered to the film 6, so that there is no possibility that the small broken funnel glass scatters far away and deviates from the above safety standard.

As is well known, a high DC voltage is applied to the cathode ray tube 1, and a smoothing capacitor is generally provided between the cathode ray tube 1 and a conductive film (not shown) such as carbon formed on the outer and inner surfaces of the funnel 3. To form a high-voltage stabilizing circuit. For this reason, the film 6 of the present invention
It is desirable to have a similar function.

Therefore, as the film 6 of the present invention, a film obtained by depositing a 10 μm thick aluminum film 12 on a 50 μm thick polyester film 11 as shown in FIG. 3 is used as an example. Then, the film 6 having such a structure is attached to the funnel 3 via the adhesive layer 13. This allows the film 6 to have a function as a smoothing capacitor (ensure the necessary capacitance as a capacitor), and to prevent the accumulation of electric charges in the cathode ray tube 1 on the film 6 and to serve as an electric / magnetic shield. Can be fulfilled.

The present invention is not limited to the above-described embodiment, but can employ various embodiments. For example, in the above-described embodiment, an example is shown in which an explosion-proof film is attached to the panel portion and the funnel portion of the cathode ray tube, but the present invention may be applied independently to the funnel portion. In addition, the present invention is a general color cathode ray tube, wide type and high-definition cathode ray tube, beam index tube,
It is needless to say that the present invention can be applied to a flat tube, a projector tube, and the like, and can be appropriately applied without departing from the gist of the present invention.

[0021]

As is apparent from the above description, according to the cathode ray tube of the present invention, for example, an explosion-proof film attached to a panel portion is attached to a cathode ray tube funnel portion. It is possible to prevent the funnel glass pieces from scattering when the pipe valve is broken. as a result,
The explosion-proof performance of the cathode ray tube bulb can be enhanced, and there is an effect that the size of the cathode ray tube can be reduced in size or flat panel.

[Brief description of the drawings]

1A and 1B are diagrams showing the external shape of a cathode ray tube, wherein FIG. 1A is a top view of the cathode ray tube, FIG. 1B is a front view of the cathode ray tube, and FIG.
FIG. 3 is a rear view of the cathode ray tube.

FIG. 2 is a front view for explaining a safety standard test of the cathode ray tube.

FIG. 3 is a cross-sectional view showing an example of an explosion-proof film used for the cathode ray tube of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Cathode tube, 2 ... Panel, 3 ... Funnel, 4 ... HS
Band, 5: panel face, 6: film, 7: X-cut, 8: scratch, 9: anode button, 10 ...
Neck, 11: Polyester film, 12: Aluminum film, 13: Adhesive layer

Claims (2)

[Claims] 1. A cathode ray tube having a functional film on an outer surface of a cathode ray tube funnel for preventing glass from scattering when a cathode ray tube bulb is broken. 2. The functional film according to claim 1, wherein the functional film is formed by laminating at least a conductive member, and the conductive member also serves as an electric / magnetic shield of the funnel portion of the cathode ray tube. Cathode ray tube.