JPH0568815B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method of manufacturing a cathode ray tube in which a plate panel is attached to a face plate.

[Technical background of the invention and its problems]

Generally, a cathode ray tube is constructed as shown in FIG. 2, with a funnel 1 joined to a face plate 2 having a fluorescent surface (not shown) on the inner surface, and an electron gun (not shown) built into the funnel 1. The screws 12 are joined together. A plate panel 3 is placed on the face plate 2 to prevent reflection of external light, improve contrast, and prevent explosions. It is filled with transparent synthetic resin 4 for adhesive fixation.

When manufacturing such a cathode ray tube, conventionally, in order to harden the transparent synthetic resin 4, it is necessary to keep it at a high temperature of about 150° C. and leave it for a certain period of time. After curing, the product is returned to normal temperature (room temperature), but if the radius of curvature 5 of the face plate 2 and the radius of curvature 6 of the plate panel 3 are different due to the temperature difference between the curing temperature and the room temperature at this time, The difference in the thickness of the transparent synthetic resin 4 is the face plate 2.
The central part 7 and the peripheral part 8 of the area are different.

For example, as shown in FIG. 2, when the radius of curvature 5 of the face plate 2 is smaller than the radius of curvature 6 of the plate panel 3, the thickness of the transparent synthetic resin 4 is thicker at the peripheral part 8 of the face plate 2. Become. In order to cure the transparent synthetic resin 4 in this state, the temperature is raised to about 150°C and after the transparent synthetic resin 4 is cured, the temperature is returned to room temperature. Since the peripheral portion 8 of the transparent synthetic resin 4 is thick, the transparent synthetic resin 4 that has expanded at high temperatures shrinks when the temperature reaches room temperature. This reduction amount is greater in the peripheral portion 8 of the face plate 2 where the transparent synthetic resin 4 is thicker. Therefore, the peripheral portion of the panel 3, which has been adhesively fixed by the transparent synthetic resin 4, is drawn to the peripheral portion 8 of the face plate 2 by that amount. As a result, the radius of curvature 6 of the plate-shaped panel 3 is smaller than the original radius of curvature of the plate-shaped panel 3.
Because there is a force that tries to return to the original radius of curvature 6,
A tensile force is always generated between the plate panel 3 and the face plate 2 with the transparent synthetic resin 4 sandwiched therebetween. For this reason, peeling between the transparent synthetic resin 4 and the plate panel 3 or peeling between the transparent synthetic resin 4 and the face plate 2 occurs over a long period of time. Further, in order to ensure the environmental resistance performance of the product, if the guaranteed temperature range is -60°C to +90°C, the above-mentioned phenomenon will be further expanded. When this peeling occurs, this part becomes a hole, and the light and refractive index of that part differs from other parts, causing the display screen to bend and discoloring that part, making it impossible to use it as a display cathode ray tube. It disappears. In addition, if the adhesive force of the transparent synthetic resin 4 is stronger than the strength of the plate-like panel 3, the plate-like panel 3
It becomes destruction. Further, these phenomena always occur when the radius of curvature 5 of the face plate 2 and the radius of curvature 6 of the plate panel 3 are different, and it has been impossible to provide a highly reliable cathode ray tube.

Therefore, as shown in FIG. 3, in order to make the radius of curvature 5 of the face plate 2 and the radius of curvature of the plate-like panel 3 the same, the surface of the plate-like panel 3 is made flat, and the face plate 2 side is A cathode ray tube with a radius of 5 has been proposed, but
It becomes a special shape and becomes an effect.

In addition, as shown in FIG. 4, the face plate 2
There are flat panel panels 3 and 3, but since the inside of the cathode ray tube is in a high vacuum,
If the face plate 2 is made flat, it will be destroyed by atmospheric pressure. It was not suitable for wide-ranging applications, such as being unable to be applied to large cathode ray tubes.

[Purpose of the invention]

The purpose of this invention is to solve the above-mentioned conventional problems, and even if the radius of curvature of the face plate and the radius of curvature of the plate-like panel are different, no extra force will be applied to the plate-like panel when it is made into a product. Thus, it is an object of the present invention to provide a method for manufacturing a cathode ray tube.

[Summary of the invention]

In the manufacturing method of the present invention, when a face plate and a plate-shaped panel having different radii of curvature are bonded and fixed using a transparent synthetic resin, the central part and the peripheral part of the face plate in the transparent synthetic resin are heated in advance from a high temperature to room temperature. Know the difference in the distance from the face plate to the transparent synthetic resin plate panel side. Next, fix the periphery of the plate panel,
Pressure is applied to the central part from the opposite direction to the transparent synthetic resin so that the drop between the central part and the periphery of the plate-shaped panel is approximately the same as the difference in change of the transparent synthetic resin,
In this state, a plate-shaped panel is placed in front of the face plate and fixed with adhesive using transparent synthetic resin, and then the pressure applied to the plate-shaped panel is removed to complete the cathode ray tube.

[Embodiments of the invention]

The method for manufacturing a cathode ray tube according to the present invention is constructed as shown in FIG.
Figure) Identical parts are given the same reference numerals.

First, the peripheral part of the plate-like panel 3 is
It is installed in a fixture 10 having a structure that does not move with respect to the pressure 9 applied perpendicularly to the surface of the fixture 10. The direction of the pressure 9 referred to here is the pressure applied to the surface of the plate panel 3 opposite to the surface facing the face plate 2.

Next, pressure 9 is applied, and when the distance from the central part 7 and peripheral part 8 of the face plate 2 to the surface of the transparent synthetic resin 4 on the plate panel 3 side after the transparent synthetic resin 4 is cured, the temperature changes from high temperature to room temperature. Know the changes and differences between This can be easily determined by calculation based on the expansion coefficient of the transparent synthetic resin 4 used, or by experiment. Then, pressure 9 is applied and fixed until a difference 11 in height between the central part and the peripheral part of the plate-like panel 3 is created which is substantially the same as this difference.

Next, in this state, a plate-like panel 3 is installed in front of the face plate 2, and a liquid transparent synthetic resin 4 that has not yet hardened is filled between the face plate 2 and the plate-like panel 3.

Next, in order to harden the transparent synthetic resin 4, it was heated to 150°C.
After the transparent synthetic resin 4 has hardened, the pressure 9 applied to the plate panel 3 and the fixing fittings 1 are
Remove 0 and return to room temperature. In this case, the pressure 9 and the fixture 10 may be removed after the temperature returns to normal temperature.

Furthermore, even if the plate-like panel 3 is fixed so that the central part of the plate-like panel 3 does not move, and the fixing fittings 10 at the peripheral part are moved in a direction perpendicular to the surface of the plate-like panel 3, the above difference will not occur. The distance is obtained.

〔Effect of the invention〕

According to this invention, even if the radius of curvature of the face plate 2 of the cathode ray tube and the radius of curvature of the plate panel 3 are different, the plate panel 3 can be attached to the face plate 2 of the cathode ray tube in a stable state at room temperature. To,
Can be installed. Furthermore, the environmental resistance can be made considerably higher than that currently available, and a highly reliable cathode ray tube can be provided. Furthermore, even if the manufacturing method of this invention is adopted, there is no extra cost;
The equipment itself may be simple.

[Brief explanation of the drawing]

FIG. 1 is a front view showing a method for manufacturing a cathode ray tube according to an embodiment of the present invention, and FIGS. 2 to 4 are front views showing a conventional method for manufacturing a cathode ray tube. 2...Face plate, 3...Plate panel,
7...Central part, 8...Peripheral part, 9...Pressure, 10
……securing bracket.

Claims (1)

[Scope of Claims] 1. A method for manufacturing a cathode ray tube in which a plate panel having a radius of curvature larger than the radius of curvature of the face plate is adhered and fixed on the face plate of the cathode ray tube with a transparent synthetic resin, , a cathode ray characterized in that it is adhesively fixed onto the face plate while maintaining a curved state approximately equal to the expected change in thickness of the transparent synthetic resin and in a direction opposite to the curve of the face plate; Method of manufacturing tubes.