JP2001110339A - Glass article for cathode-ray tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide glass articles for cathode-ray tubes that improves stability of positioning and do not produce formation failure at standard portions caused by concentrating heat stress. SOLUTION: Glass article according to this invention is formed by a plurality of reference parts for positioning on an outer wall placed closely to an opening edge 21 for sealing that is approximately a rectangle with long and short sides. Long-side reference parts 22a and 22b are formed in the vicinity of both ends of a long side on the outer wall on the long side of the opening edge 21 for sealing, and a short-side reference parts 22c is formed at a position apart from the corner portion 23 adjacent to the long-side reference part 22b by more than 2/5 of the length of the short side on the outer wall on the short side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glass article for a cathode ray tube, and more particularly to a glass panel and a funnel for a cathode ray tube having a reference portion for positioning on an outer wall thereof.

[0002]

2. Description of the Related Art A glass bulb for a cathode ray tube has a front panel serving as an image display unit, a funnel behind the front panel, which is sealed to the panel, and a deflection yoke is mounted on the outside, and which is welded to the funnel and has an electronic component inside. It consists of a neck where the gun is stored.

The panel serving as the image display unit and the funnel sealed to the panel both have a substantially rectangular sealing opening end, and the sealing opening is interposed between the panel and the funnel. The funnel is sealed.

In order to display a proper image without color shift or the like during operation of the cathode ray tube, the axes of the panel, funnel and neck are accurately aligned with each other with respect to the tube axis of the glass bulb. Must be done.
Therefore, in the panel or funnel, a plurality of positioning reference portions are formed on an outer wall close to the substantially rectangular sealing opening end portion, and these reference portions are brought into contact with a jig during sealing. By doing so, positioning is performed. The reference surface of the reference portion is formed at a predetermined distance from the axis of the panel or funnel.

In a conventional panel and funnel, as shown in FIGS. 6 to 9, a sealing opening end 1 of a panel P is provided.
Alternatively, on the outer wall on the long side of the sealing opening end 11 of the funnel F, a reference portion 12a, 1
2b is formed, and a reference portion 12c is formed on the outer wall on one short side at a position close to the corner portion 13 adjacent to the reference portion 12b on the long side, and a reference portion on the short side is formed. The position is formed at a position away from the corner 13 by about 1/6 of the length of the short side.

[0006] Panels and funnels are press-formed by supplying a high-temperature molten glass mass to a molding die composed of a bottom die and a body die, lowering a pressing die and extending the molten glass mass. The reference portion is also formed at the same time as the press molding, and the reference surface of the reference portion may be polished as necessary.

[0007]

In the conventional glass article for a cathode ray tube, one of the reference portions on the long side and the reference portion on the short side are formed close to each other with a corner portion therebetween. Due to this, the positioning stability of the glass article is poor, and a misalignment occurs when the glass article is placed on the gantry in the sealing step, and the glass article is sealed without obtaining the original consistency between the panel and the funnel There is. In this way, in the glass tube for a cathode ray tube in which the sealing opening end of the panel and the funnel is displaced, not only does the image color shift and distortion occur when the cathode ray tube is activated, but also the panel and the funnel do not. Insufficient sealing between funnels may cause a decrease in strength, and for example, during heat treatment in an exhaust process after sealing, the glass bulb may be damaged due to the poor sealing.

In the funnel, the reference portion has a shape protruding outward from the outer wall, and the glass thickness is sharply increased at the reference portion. Concentration of thermal stress is likely to occur at one of the reference portions on the side and the reference portion on the short side. At the end of the substantially rectangular sealing opening, thermal stress is likely to be generated at a corner portion that becomes a bending point. In addition, the close arrangement of the reference portion as described above causes a sudden change in shape. Therefore, a higher thermal stress is generated in the two adjacent reference portions than in the other region where the reference portion is not formed or the other reference portion on the long side. As a result, as the temperature decreases and rises in the molding step of the glass article for a cathode ray tube,
Cracks are likely to occur in one of the reference portions, causing a molding defect called a check.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a glass article for a cathode ray tube, which improves the positioning stability and does not cause molding failure of a reference portion due to concentration of thermal stress.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems and objects, and has an outer wall near a rectangular opening end having a long side and a short side. A glass article for a cathode ray tube having a plurality of reference portions formed thereon, and an outer wall on a long side of the sealing opening end portion includes:
A long-side reference portion is formed near both ends on the long side, and the outer wall on the short side is separated from the corner adjacent to the long-side reference portion by at least 2/5 of the length of the short side. A glass article for a cathode ray tube, wherein a short-side reference portion is formed at a position.

In the present invention, more preferably, the short-side reference portion is formed at a position separated from a corner adjacent to the long-side reference portion by 6/7 or less of the length of the short side.

Further, in the present invention, more preferably, the short-side reference portion is formed at a position separated from the corner portion adjacent to the long-side reference portion by at least half the length of the short side.

In the present invention, the lengths of the long side and the short side are
It means the linear distance between the intermediate points of both corners on the shorter side of the substantially rectangular sealing opening end, and the separation distance is the linear distance from the intermediate point of the corner to the center point of the reference part.

[0014]

According to the present invention, a long side reference portion is formed at both ends of a long side of an outer wall on a long side of a sealing opening end portion, and the long side reference portion is formed on a short side outer wall. The short-side reference portion is formed at a position at least 2/5 of the length of the short side from the corner portion adjacent to the above, so that the stability at the time of positioning the glass article for a cathode ray tube is extremely improved, The short-side reference portion formed across the corner portion is separated from the corner portion adjacent to the one long-side reference portion and the corner portion adjacent to the long-side reference portion, so that the short-side reference portion is formed across the corner portion. The concentration of thermal stress generated in the two reference portions can be reduced.

When three reference portions are used, it is important to position two of them on the long side from the viewpoint of the positioning stability of the glass article for a cathode ray tube. Since a span as long as possible is required, it is formed near both ends on the long side.

In the present invention, more preferably,
The short side reference portion is formed at a position separated from the corner portion close to the long side reference portion by 6/7 or less of the length of the short side because the short side reference portion is 6/7 of the length of the short side from the corner portion. When the short-side reference portion is formed at a position beyond the short-side reference portion, the short-side reference portion is too close to the other corner portion on the short side side, in combination with the influence of thermal stress at the corner portion. This is because the concentration of thermal stress tends to occur easily.

In the present invention, more preferably,
By forming the short-side reference portion at a position separated by 以上 or more, the stability at the time of positioning the glass article is further improved.

[0018]

Hereinafter, the glass article for a cathode ray tube of the present invention will be described based on examples.

FIGS. 1 to 5 are front views of a sealing opening end for explaining a position of a reference portion of a funnel according to the present invention.

(Embodiment 1) In this embodiment, as shown in FIG. 1, a substantially rectangular sealing opening end 21 of a funnel F having a diagonal dimension of 720.0 mm (29 type aspect ratio 4: 3) is used.
The outer wall on one long side of the sealing opening end 21 near the both ends on the long side has corners 23, 23 of both ends on the long side of the sealing opening end 21 near the long side. Long-side reference portions 22a and 22b are formed at positions 94.5 mm away from the intermediate point M, respectively. On the outer wall on one short side, a short side reference portion 22c is formed at a position 189.0 mm away from an intermediate point M of the corner portion 23 adjacent to the long side reference portion 22b. Opening end 2 for sealing
1 has a length of 472.5 mm, and therefore, the short-side reference portion 22c is located at a distance of ／ of the short-side length from the corner portion 23 adjacent to the long-side reference portion 22b. It is formed in.

The long-side reference portions 22a and 22b and the short-side reference portion 22c are formed at the same time when the funnel F is press-formed, and as a result of the matching of the bottom die and the die, the sealing opening ends are formed. It is formed on a mold match line formed near the portion 21. In addition, the long side reference portion 2
2a, 22b and the short side reference portion 22c are
It has a reference surface of 3 mm and a width of 22 mm, and has a shape protruding from the outer wall.

(Embodiment 2) In this embodiment, as shown in FIG. 2, an outer wall on one short side of the sealing opening end 21 is provided between the corner 23 adjacent to the long side reference portion 22b. The short side reference portion 22c is located 210.0 mm away from the point M.
Is formed. Other conditions are the same as those in the first embodiment. Therefore, the short-side reference portion 22c is
It is located at a distance of 4/9 of the length of the short side from the corner 23 adjacent to 2b.

(Embodiment 3) In this embodiment, as shown in FIG. 3, an outer wall on one short side of the sealing opening end 21 is provided between the corner 23 adjacent to the long side reference portion 22b. 236.2 mm away from point M, short-side reference portion 22c
Is formed. Other conditions are the same as those of the first embodiment. Therefore, the short-side reference portion 22c is
It is located at a position separated from the corner 23 adjacent to b by の of the length of the short side.

(Embodiment 4) In this embodiment, as shown in FIG. 4, an outer wall on one short side of the sealing opening end 21 is provided between the corner 23 adjacent to the long side reference portion 22b. A short side reference portion 22c at a position 315.0 mm away from the point M
Is formed. The other conditions are the same as those of the first embodiment. Therefore, the short side reference portion 22c is ２ of the length of the short side from the corner 23 adjacent to the long side reference portion 22b.
It is located three spaces away.

(Embodiment 5) In this embodiment, as shown in FIG. 5, an outer wall on one short side of the sealing opening end 21 is provided between the corner 23 adjacent to the long side reference portion 22b. A short side reference portion 22c is located at a position 405.0 mm away from the point M.
Is formed. Other conditions are the same as those of the first embodiment. Therefore, the short-side reference portion 22c is
It is formed at a position spaced 6/7 of the length of the short side from the corner 23 adjacent to b.

(Comparative Example 1) A funnel having the same dimensions as that of the above-described embodiment, and the outer wall on one short side of the substantially rectangular sealing opening end is located at the middle of the corner adjacent to the long side reference portion. A short-side reference portion is formed at a position 78.7 mm away from the point. The other conditions are the same as those of the above-described embodiment. Therefore, the short-side reference portion is located at a position separated from the corner portion adjacent to the long-side reference portion by ６ of the length of the short side.

(Comparative Example 2) A funnel having the same dimensions as that of the above-described embodiment, and an outer wall on one short side of a substantially rectangular sealing opening end is provided at an intermediate portion of a corner adjacent to a long side reference portion. A short-side reference portion is formed at a position 157.5 mm away from the point. The other conditions are the same as those of the above-described embodiment. Therefore, the short-side reference portion is located at a position separated from the corner adjacent to the long-side reference portion by １ ／ of the length of the short side.

(Comparative Example 3) A funnel having the same dimensions as that of the above-described embodiment, and the outer wall on one short side of the substantially rectangular sealing opening end is located at the middle of the corner adjacent to the long side reference portion. A short-side reference portion is formed at a position 420.0 mm away from the point. The other conditions are the same as those of the above-described embodiment. Therefore, the short-side reference portion is located at a position 8/9 of the length of the short side from the corner adjacent to the long-side reference portion.

With respect to each of the funnels of Examples 1 to 5 and Comparative Examples 1 to 3, in order to evaluate the moldability of the reference portion, 500 such funnels were produced, and the concentration of thermal stress in the funnel molding step was increased. The number of cracks generated in the reference portion due to the above was examined. The reference portion covers two reference portions, one long side reference portion on the long side and a short side reference portion formed on the short side through a corner portion adjacent to the long side reference portion. did. Further, in order to evaluate the positioning stability, a panel having a reference portion at a position corresponding to the reference portion of each of the funnels of Examples 1 to 5 and Comparative Examples 1 to 3 was formed, and each funnel and its corresponding panel were formed. To be sealed with a sealing glass interposed therebetween, to prepare 500 funnel-panel sealed bodies each, and baked in a furnace at 430 ° C. for 1 hour to determine the number of breaks in the funnel-panel sealed bodies. Examined. As for the damage, the damage origin was confirmed by the damage analysis, and only the damage caused by poor sealing caused by the mismatch between the panel and the funnel was regarded as the number of damages.

Table 1 shows the results.

[0031]

[Table 1]

With respect to the funnels and funnel-panel seals of Examples 1 to 5, the number of occurrences of molding defects at the reference portion and the number of breaks in the funnel-panel seals were extremely low as compared with Comparative Examples 1 to 3. . From this, for the glass article for a cathode ray tube of the present example, the thermal stress generated in the reference portion for positioning can be reduced, and the positioning stability at the time of sealing is extremely high, and excellent matching can be obtained. You can see that

[0033]

As described above, according to the glass article for a cathode ray tube of the present invention, the positioning stability at the time of sealing can be improved, the concentration of thermal stress can be reduced, and the molding failure at the reference portion. This has an excellent effect of not causing the occurrence.

[Brief description of the drawings]

FIG. 1 is a front view of a sealing open end of a funnel according to the present invention.

FIG. 2 is a front view of a sealing opening end of a funnel according to the present invention.

FIG. 3 is a front view of a sealing opening end of a funnel according to the present invention.

FIG. 4 is a front view of a sealing opening end of a funnel according to the present invention.

FIG. 5 is a front view of a sealing opening end of a funnel according to the present invention.

FIG. 6 is a perspective view of a conventional panel.

FIG. 7 is a front view of a sealing opening end of a conventional panel.

FIG. 8 is a perspective view of a conventional funnel.

FIG. 9 is a front view of a sealing opening end of a conventional funnel.

[Explanation of symbols]

 11, 21 Sealing opening end 12a, 12b, 12c Reference portion 13, 23 Corner 22a, 22b Long side reference portion 22c Short side reference portion M Intermediate point F Funnel P panel

Claims (3)

[Claims] 1. A glass article for a cathode ray tube having a plurality of positioning reference portions formed on an outer wall adjacent to a substantially rectangular sealing opening end having a long side and a short side, wherein the sealing opening end is provided. A long-side reference portion is formed near both ends on the long side of the outer wall on the long side of the portion, and a short-side outer wall has a short side from a corner portion adjacent to the long-side reference portion. A glass article for a cathode ray tube, wherein a short-side reference portion is formed at a position separated by at least 2/5 of the length of the glass article. 2. The short-side reference portion is formed at a position separated from a corner portion adjacent to the long-side reference portion by 6/7 or less of the length of the short side. The glass article for a cathode ray tube according to the above. 3. The short-side reference portion is formed at a position separated from the corner portion adjacent to the long-side reference portion by at least half the length of the short side. Glass articles for cathode ray tubes.