JPS62202446A - Vacuum container for image display device - Google Patents

Abstract

PURPOSE:To provide an image display device of low weight, by reducing the thickness of the corner and skirt (peripheral portion) of a faceplate to uniform the rigidity thereof to decrease the weight of a vacuum container. CONSTITUTION:To manufacture a faceplate 1, the peripheral portion of a plate glass of 10mm in thickness is pinched by a sash-like jig, the plate glass is heated at a temperature of about 650-750 deg.C, and the central portion of the glass is protruded as a dish. Since the central portion of the plate glass is not touched but the peripheral portion thereof is pinched in protruding the central portion, the front surface 7 thereof has the same flatness and roughness as the original plate glass. The faceplate 1 thus formed is immersed in a molten potassium salt at a temperature of about 450-500 deg.C for a long time to substitute the potassium of the plate glass for the sodium thereof to chemically reinforce the faceplate. Studs 4 are thereafter bonded to the faceplate 1 by crystalline frit at a temperature of about 450 deg.C in a furnace.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a vacuum container used in an image display device.

2. Description of the Related Art Braun tubes have been well known as vacuum containers for image display devices. As shown in FIG. 2, the cathode ray tube has an electron beam gun 11. Panel 12°Funnel 13. Shadow mask 14. Stud pin 16. Sealing frit 16
It consists of The cross-sectional shape of the panel 12 is determined by pressing the melted glass F-7'' By the way, the cathode ray tube 20 has a vacuum level of 10-6 to 1o-7 torr inside the container in order to dissipate the electron beam.When the vacuum is created, the atmosphere causes the cathode ray tube 2o to move inside. When compressed, vacuum strain occurs on the outer surfaces of the panel 12 and the funnel 13 as shown in FIG. 25 L2
APr 1979). The face portion 17 is a portion that can be directly touched by the user of the image display device, and is easily damaged by chips, dirt, and the like. When a scratch occurs in the tensile stress portion of the face portion 17, stress concentration occurs, and when the strength of the material is added to this stress, the scratch becomes more elongated, eventually causing the cathode ray tube 20 to break. Therefore, even if the cathode ray tube 2o has a face part 1
Even if 7 is scratched and stress concentration occurs, the thickness of the panel 12 is made thicker so that the tensile stress does not exceed the strength of the material, and the skirt portion 19 near the corner portion is made of thicker glass. There is.

Problems to be Solved by the Invention However, in the above configuration, the rigidity of the skirt portion 19 and the corner portion 18 is made too large compared to the rigidity of the face portion 1A.
It has a fatty shape.

Therefore, the cathode ray tube 20 is heavy and difficult to handle. The current cathode ray tube 2o is 16 inches and about 8 to 9
kilogram, which is approximately 10 to 14 kilograms in 21 inches. Therefore, it is not portable and requires a sturdy base for installation. Furthermore, the surface of the panel 12 has a curvature,
Since it reflects a wide range of disturbance light, it has the disadvantage that the image is difficult to see. Therefore, the present invention attempts to obtain a structure that can ensure safety even when the weight is reduced by making the surface of the panel 12 nearly flat and making the thickness of the glass plate warp.

Means for solving the problems and technical means of the present invention for solving the above problems are as follows:
■ To equalize the rigidity of the panel by removing the flab at the corners and skirt, and ■ To transfer the maximum tensile stress from the face to the skirt, which the user does not touch. The thickness of the glass plate (and skirt portion) is made thinner than that of the face portion where the image is displayed. Furthermore, in order to reduce the tensile stress generated in a vacuum, a layer to which compressive stress is applied in advance is formed on the glass surface.

For production The effect of this technical means is as follows.

The glass in a cathode ray tube breaks because the tensile stress generated on the glass surface by the vacuum causes stress concentration at the tips of microcracks on the glass surface caused by handling, and the stress exceeds the strength of the material. Therefore, if compressive stress is applied to the glass surface in advance through chemical strengthening treatment or the like, the tensile stress caused by the vacuum is subtracted, and the strength of the vacuum container is greatly improved, even more than the strength of the material.

However, since the layer to which compressive stress is applied by this chemical strengthening treatment is only about 1 to 20 micrometers below the glass surface, the above effects cannot be expected if scratches caused by handling penetrate this layer. Therefore, if the maximum tensile stress portion is placed in an area that cannot be touched by the user's hands, no scratches will occur and the effect of the chemically strengthened layer will be fully exhibited.

The shape of this vacuum container is such that the thickness of the corner and the skirt near the corner (thickness of the side surface) is smaller than the thickness of the face where the image is displayed, so that the maximum tensile stress can be reduced. The surface of the side surface is now covered with grains.

EXAMPLE An example of the present invention will be described below with reference to FIGS. 1 and 4. In FIG. 1, 1 is a front panel that displays an image and forms a vacuum container. Reference numeral 2 designates a back panel that is sealed with the panel using a frit 3 to form a vacuum container. 3 is a frit for bonding the front panel 1 and the back panel 2 together. 4 is the rj of the vacuum container: JfGF b old 8 = t2. f+h
'r combination & L) 7 ffl ・7 k ノζ
+-IL 4 This is a stud bottle glued with 1f frit 3.

Reference numeral 5 denotes an electrode structure composed of various electrodes and fluorescent materials for displaying images. Reference numeral 6 denotes a support spring for attaching the electrode structure 5 to the stud bin 4. Reference numeral 7 denotes an area where images are displayed through the front panel 1, which is the face portion of the front panel 1. Reference numeral 8 indicates a corner portion of the front panel 1. Reference numeral 9 denotes a skirt portion of the front panel 1. 1o is a cracked portion of the front panel 1. The thickness of the face portion 7 of the front panel 1 shown in FIG. 1 is approximately 10 mm, the thickness of the corner portion 8 is approximately 7 to 9 mm, and the thickness of the skirt portion 9 is approximately 6 to 8 mm.
millimeters, and the plate thickness of the flange portion 10 is about 5 to 7 millimeters. The front panel 1 is made by sandwiching the periphery of a 10 mm thick plate glass between window frame-shaped jigs, heating it to a temperature of approximately 650 to 760 degrees Celsius, and sticking out the central part in a dish shape. molded. In addition, since the overhang is not done by touching the central part, but rather by using the corner parts 8, the face part 7 inherits the flatness and roughness of the sheet glass. Next, the front panel 1 that has been molded
The sheet glass is chemically strengthened by being immersed in potassium molten salt heated to about 450 to 5°C for a long time to replace the sodium and potassium components of the sheet glass. Then, the chemically strengthened front panel 1 is placed in a furnace at about 450° C., and the stud pins 4 are bonded thereto using crystalline frit.

The front panel 1 thus created is as shown in FIG. 1, and the front panel 1 has an electrode structure 5 for image display
is assembled into the stud pin 4 via the support spring 6.

Thereafter, a back panel 2 made by a similar glass molding method is placed on the front panel 1, and sealed by firing the amorphous frit in a furnace at about 450°C.

After sealing the vacuum container, air is removed from the chip tube (not shown in Figure 1) installed in advance on the pack panel 2, and the inside of the container is vacuumed at 10-6 to 1o Torr. Make it. When a vacuum is created, the vacuum container is compressed inward by the atmosphere, and a vacuum strain as shown in FIG. By the way, when the vacuum container is assembled into a set, only the face part 7 is exposed, so the user must
The skirt portion 9 cannot be bent, so there is no need to worry about damage, and the effect of chemical strengthening will not be nullified.

Compared to conventional cathode ray tube panels, the vacuum container made in this way has a reduced thickness at the corners and skirt (side surface), making it possible to reduce the weight by about 40%.

Effects of the Invention The present invention reduces the thickness of the corner portions and skirt portions (side portions) of the panel to ensure uniform rigidity.
Another major advantage is that the vacuum container can be made lighter, making it easier to carry, and making it possible to create a lightweight image display device.

In addition, in conventional cathode ray tube panels, the maximum tensile stress occurs in the face part, but the vacuum container of the present invention is composed of a glass molded body having a layer with compressive stress on the surface, so that the user can easily Virtually no tensile stress is generated on the face, which is touched by hands, and is highly safe against scratches.

[Brief explanation of drawings]

Fig. 1 is a sectional view of an embodiment of the present invention, Fig. 2 is a sectional view of a conventional cathode ray tube, Fig. 3 is a stress distribution diagram of a conventional cathode ray tube, and Fig. 4 is a vacuum vessel in the above embodiment of the invention. FIG. 7...Face part, 8, 9... Side part. Name of agent: Patent attorney Toshio Nakao and 1 other person1°
-20 outside t\1le 2-゛-88tsu7meV+half-ru-<棧樨Gento11i-fi, Ttanha special? --7f-Suit and 1O---Fran Y Leech Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] A vacuum container for an image display device, comprising a glass molded body having a side surface having a thickness thinner than that of a face for displaying an image, and having a layer to which compressive stress is applied to the surface.