JPH08129961A - Color cathode-ray tube - Google Patents

Abstract

PURPOSE: To prevent deformation of a frame body by tensile force of a shadow mask by enhancing rigidity of the frame body to support the shadow mask in a stretching condition without increasing weight and without complicating a work process. CONSTITUTION: Side wall parts 42 are continuously formed on the inner periphery of the respective sides 41a and 41b of an almost rectangular frame shaped shadow mask welding part 41 whose respective sides continue with each other, and parts 42a perpendicular to the shadow mask welding part and inward inclining parts 42b acting as ribs are alternately arranged in the side wall parts 42.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color cathode ray tube, and more particularly to a flat color cathode ray tube having a shadow mask fixed to a frame under a constant tension.

[0002]

2. Description of the Related Art In a flat color cathode ray tube, about 80% of an electron beam emitted from an electron gun collides with a shadow mask, and the shadow mask generates heat and tends to be deformed by thermal expansion. In order to prevent the deterioration of image quality due to the deformation of the shadow mask, it has been conventionally performed to fix the shadow mask (blank) to a frame (frame body) with a certain tension.

However, when the rigidity of the frame is not sufficient,
The frame is deformed by the tension applied to the shadow mask, causing wrinkles on the surface of the shadow mask, and the relative positions of the electron beam transmission holes of the shadow mask and the phosphors on the screen do not match, causing a color shift in the color cathode ray tube. Occurs. As one of the methods for preventing such deformation of the frame body, for example, as described in Japanese Patent Laid-Open No. 3-187132, the cross section of each side of the frame body is made substantially triangular to increase the rigidity of the frame body. It is suggested to do so.

On the other hand, the aspect ratio of the screen of the flat color cathode-ray tube is 3: 4 or 9:16, which is horizontally long. When tension is applied to the shadow mask, the tension on the long side is strong, so that the long side of the frame body is displaced inward and the short side is displaced outward. In order to prevent such movement of the long side and the short side of the frame body from interlocking with each other, for example, JP-A-5-29
As described in Japanese Patent No. 0754, it has been proposed to provide a notch at a corner portion or the like of a frame body and independently displace the long side and the short side of the frame body.

[0005]

However, in the case of making the cross section of each side of the frame body substantially triangular, the reinforcing piece is obliquely welded to the side wall portion perpendicular to the mask surface and the flange portion parallel to the mask surface, or A plate material having a substantially triangular cross section or a bar material having a substantially triangular cross section must be welded at each corner, which increases the weight of the frame and complicates the frame manufacturing process. There is a problem that the manufacturing cost of the body becomes high. On the other hand, when the cutouts are provided at the corners of the frame body, the tension of the shadow mask becomes uneven at the cutouts, causing wrinkles at the cutouts, which causes color unevenness.

The present invention has been made in order to solve the above-mentioned problems, and does not increase the weight of the frame body and complicate the working process, and the frame body is maintained at a constant tension. It is an object of the present invention to provide a color cathode ray tube having a shadow mask which does not cause wrinkles even when welded to the.

[0007]

In order to achieve the above object, the color cathode ray tube of the present invention comprises a shadow mask welded portion having a substantially rectangular frame shape in which each side is continuous and each side of the shadow mask welded portion. A side wall portion continuously formed on the circumference and having a portion perpendicular to the shadow mask welding portion and a portion inclined inwardly alternately, and a side wall portion continuously formed and parallel to the shadow mask welding portion. And a shadow mask welded to the shadow mask welding surface of the frame in a state where a predetermined tension is applied. In the above configuration, the ridge of the inclined portion of the side wall portion is substantially parallel to the side of the shadow mask welded portion, and in a plane perpendicular to the shadow mask, the shadow mask welded portion provided on the side wall portion. It is preferable that a substantially triangular opening is formed by the perpendicular portion and the inclined portion and the flange portion. Further, in the above configuration, on the long side and the short side of the frame body, at least one of the size and the number of a portion perpendicular to the shadow mask welding portion provided on the side wall portion and a portion inclined inward. It is preferable that one is different.

In another color cathode ray tube of the present invention, the shadow mask welded portion having a substantially rectangular frame shape having continuous sides and the shadow formed continuously on the inner circumference of each side of the shadow mask welded portion. A side wall portion provided so that a portion perpendicular to the mask welding portion and a portion inclined inward and outward are repeatedly continuous, and a flange portion formed continuously with the side wall portion and parallel to the shadow mask welding portion. And a shadow mask welded to the shadow mask welding surface of the frame in a state in which a predetermined tension is applied. In the above structure, it is preferable that the ridgeline of the side wall part and the shadow mask welded part is a straight line, and the ridgeline of the side wall part and the flange part is a wavy line.

In each of the above structures, it is preferable that a cross section of the side wall portion parallel to the shadow mask in the vicinity of the boundary with the shadow mask welded portion is substantially octagonal. Further, it is preferable that the frame body is integrally formed by press molding. Further, the thermal expansion coefficient of the material of the frame body is preferably smaller than the thermal expansion coefficient of the material of the shadow mask.

[0010]

According to the color cathode ray tube of the present invention constructed as described above, the portion inclined with respect to the shadow mask welded portion formed on the side wall portion of the frame acts as a rib, and the weight of the frame increases. Without increasing the rigidity of the frame body against the tension of the shadow mask. Therefore, the deformation of the frame body due to the tension of the shadow mask is prevented. Further, since each side of the shadow mask welded portion is continuous and no cutout or the like is provided at the corner portion, the tension of the shadow mask does not become uneven at the corner portion, and wrinkles do not occur at that portion. . The ridgeline of the inclined part of the side wall part is made substantially parallel to the side of the shadow mask welding part, and in the surface perpendicular to the shadow mask, the part perpendicular to the shadow mask welding part provided on the side wall part and the inclined part and the flange. By forming a substantially triangular opening with the portion, press working becomes possible and the mechanical strength becomes uniform over almost the entire side wall portion. By changing at least one of the size and the number of the portion perpendicular to the shadow mask welded portion provided on the side wall portion and the portion inclined inward on the long side and the short side of the frame, each side It is possible to arbitrarily adjust the mechanical strength of each side of the frame body according to the length of the shadow mask and the tension of the shadow mask.

Further, the side wall portion is provided with a portion perpendicular to the shadow mask welded portion and a portion inclined inward and outward so as to be continuous, and the ridge line of the side wall portion and the shadow mask welded portion is a straight line. Even if the ridgeline between the and the flange portion is formed into a corrugated shape, it is possible to perform press working in the same manner, and the mechanical strength becomes uniform over almost the entire sidewall portion. Also,
In the vicinity of the boundary with the shadow mask weld, by making the cross section of the side wall portion parallel to the shadow mask into a substantially octagonal shape, a gap is formed between each corner portion of the shadow mask weld and the side wall, The shape of each corner of the shadow mask weld is stable during processing, and the flatness of the shadow mask weld is maintained. Further, by making the thermal expansion coefficient of the material of the frame body smaller than the thermal expansion coefficient of the material of the shadow mask, the thermal capacity of the shadow mask and the frame body at the time of joining the glass funnel of the color cathode ray tube and the panel. It is possible to prevent plastic deformation of the shadow mask due to the difference.

[0012]

【Example】

(First Embodiment) First Preferred Embodiment of Color Cathode Ray Tube of the Present Invention
The embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is a sectional view showing the structure of a color cathode ray tube according to the first embodiment, and FIG. 2 is a perspective view showing the shape of a frame body (frame) 4 for supporting a shadow mask. As shown in FIG. 1, the color cathode ray tube of the first embodiment is a funnel 1 made of glass or the like and a panel 2 made of glass or the like.
And a phosphor screen 8 provided on the inner surface of the panel 2, and a phosphor screen 8
The shadow mask 3 provided substantially parallel to the shadow mask 3, a frame 4 for supporting the shadow mask 3, and an electron gun (not shown) provided on the neck portion 6 of the funnel 1. For example, electron beams 7 corresponding to RGB colors emitted from the in-line type electron gun 6 respectively pass through predetermined electron beam transmission holes provided in the shadow mask 3 and correspond to RGB colors on the fluorescent screen 8. Reach the phosphor. Each phosphor irradiated with the electron beam 7 emits each color of RGB, and a color image is formed on the panel 2.

As shown in FIG. 2, the frame body 4 has a substantially rectangular cross section, and a shadow mask 3 (not shown in FIG. 2) for welding a shadow mask 3 is welded to one open end of the frame body 4. Mask 3
A shadow mask welded portion 41 parallel to is formed.
Further, a flange 43 parallel to the shadow mask welding portion 41 is formed at the other open end of the frame body 4. The shadow mask welded portion 41 has a substantially rectangular frame shape in which each side (long side) 41a and (short side) 41b are continuous, and each corner portion 41c is not provided with a cutout or the like. Continuing on the inner circumference of each side 41a and 41b of the shadow mask welded portion 41,
The side wall portion 42 is integrally formed. The side wall portion 42 has a portion 42a perpendicular to the shadow mask weld portion 41.
And inwardly inclined portions 42b are provided alternately. Further, the side wall portion 42 and the flange portion 43 are continuously and integrally formed.

That is, the frame body 4 shown in FIG. 2 is integrally formed by pressing or the like. In order to facilitate the press working, the slope 4 of the inclined portion 42b of the side wall portion 42
2c is the sides 41a and 41b of the shadow mask welded portion 41.
And approximately parallel to. Further, in a plane perpendicular to the shadow mask 3, a portion 42 a perpendicular to the shadow mask welding portion 41 provided on the side wall portion 42 and an inclined portion 4 are provided.
2b and the flange portion 43 form a substantially triangular opening 42d. Further, the cross section of the side wall portion 42 parallel to the shadow mask in the vicinity of the boundary with the shadow mask welded portion 41 has a substantially octagonal shape. As a result, the shadow mask weld 4
The gap 41 is formed between each of the corner portions 41c of FIG.
d is formed, the shape of each corner portion 41c of the shadow mask welded portion 41 during press working is stabilized, and the flatness of the shadow mask welded portion 41 is maintained.

Further, the long side 41a side and the short side 41b of the frame body 4 are
On the side, depending on the length of each side 41a and 41b and the tension of the shadow mask 3, the dimensions of the portion 42a perpendicular to the shadow mask welded portion 41 provided on the side wall portion 42 and the portion 42b inclined inward, and Change at least one of the numbers. In this embodiment, the width of the portion 42a perpendicular to the shadow mask welded portion 41 and the number of the inclined portions 42b are changed.

With the above-described structure, the portion 42b inclined with respect to the shadow mask welded portion 41 formed on the side wall portion 42 of the frame body 4 acts as a rib, so that the weight of the frame body 4 is not increased and the shadow is eliminated. The rigidity of the frame body 4 against the tension of the mask 3 can be increased, and the deformation of the frame body 4 due to the tension of the shadow mask 3 can be prevented. Further, since the respective sides 41a and 41b of the shadow mask welded portion 41 are continuous and the corner portion 41c is not provided with a notch or the like, the tension of the shadow mask 3 does not become uneven at the corner portion 41c, No wrinkles are formed on that portion of the shadow mask 3.

(Second Embodiment) Next, a second preferred embodiment of the color cathode ray tube of the present invention will be described with reference to FIGS. 3 and 4. FIG. 3 is a perspective view showing the shape of a frame body (frame) for supporting the shadow mask in the second embodiment. Moreover, (a), (b) and (c) in FIG. 4 show an AA cross section, a BB cross section and a CC cross section in FIG. 3, respectively. The configuration of the color cathode ray tube of the second embodiment is substantially the same as the configuration of the color cathode ray tube of the first embodiment shown in FIG. 1, and only the shape of the frame 4 is different. Therefore, the description of the configuration of the color cathode ray tube of the second embodiment is omitted.

As shown in FIG. 3, similarly to the first embodiment, the frame body 4 in the second embodiment has a substantially rectangular cross section,
A shadow mask weld portion 41 parallel to the shadow mask 3 for welding the shadow mask 3 (not shown in FIG. 3) is formed at one end of the opening. Also,
At the other end of the opening of the frame body 4, the shadow mask welding portion 4
A flange 43 parallel to 1 is formed. The shadow mask welding portion 41 has each side (long side) 41a and (short side) 4
1b is a continuous rectangular frame shape, and each corner portion 41c
There are no cutouts, etc. A side wall portion 45 is integrally formed so as to be continuous with the inner circumference of each side 41a and 41b of the shadow mask welded portion 41. The side wall portion 45 is repeatedly continuous with a portion perpendicular to the shadow mask welding portion 41 (BB cross section), an inwardly inclined portion (CC cross section), and an outwardly inclined portion (AA cross section). Is provided. Further, the side wall portion 42 and the flange portion 43 are continuously and integrally formed. The side wall 45 and the ridge 45a of the shadow mask welded portion 41 are straight lines, and the side wall 45
The ridgeline 45b between the and the flange portion 43 is corrugated.

Further, similar to the first embodiment, the cross section of the side wall portion 45 in the vicinity of the boundary with the shadow mask welded portion 41, which is parallel to the shadow mask, has a substantially octagonal shape. Thereby, a gap 41d is formed between each corner portion 41c of the shadow mask welded portion 41 and the side wall portion 45, and each corner portion 41c of the shadow mask welded portion 41 during press working.
Is stable, and the flatness of the shadow mask welded portion 41 is maintained.

With the above structure, the shadow mask welded portion 41 formed on the side wall portion 45 of the frame 4 is inclined inward (section CC) and outwardly inclined (section AA). ) Acts as a rib, the rigidity of the frame body 4 with respect to the tension of the shadow mask 3 can be increased without increasing the weight of the frame body 4, and the deformation of the frame body 4 due to the tension of the shadow mask 3 is prevented. It Further, since the respective sides 41a and 41b of the shadow mask welded portion 41 are continuous and the corner portion 41c is not provided with a notch or the like, the tension of the shadow mask 3 does not become uneven at the corner portion 41c, No wrinkles are formed on that portion of the shadow mask 3.

In each of the above embodiments, a soft steel plate, for example, is used as the material of the shadow mask 3, and 13% Cr- whose coefficient of thermal expansion is smaller than that of the soft steel plate as the material of the frame body 4.
Fe, 18% Cr-Fe, 50% Ni-Fe and 42%
Ni-Fe or the like is used. As a result, when the funnel 1 and the panel 2 are joined, the expansion of the frame body 4 is smaller than the expansion of the shadow mask 3 even if it is exposed to a high temperature (for example, 450 degrees) for a long time. The material does not exceed the elastic limit, and the plastic deformation of the shadow mask 3 can be prevented.

[0022]

As described above, according to the color cathode ray tube of the present invention, since the inclined portion with respect to the shadow mask welding portion formed on the side wall portion of the frame acts as a rib, the weight of the frame is reduced. The rigidity of the frame body against the tension of the shadow mask can be increased without increasing, and the deformation of the frame body due to the tension of the shadow mask can be prevented. In addition, since each side of the shadow mask weld is continuous and no cutouts are provided at the corners, the tension of the shadow mask does not become uneven at the corners, and the occurrence of wrinkles at that part is prevented. You can Further, the ridgeline of the inclined portion of the side wall portion is made substantially parallel to the side of the shadow mask welded portion, and in the surface vertical to the shadow mask, the portion perpendicular to the shadow mask welded portion provided on the side wall portion and the inclined portion. Since the substantially triangular opening is formed by the flange portion and the flange portion, the frame body can be integrally formed by press working, and the mechanical strength can be made uniform over almost the entire side wall portion. Furthermore, on the long side and the short side of the frame body, by making at least one of the size and the number of the portion perpendicular to the shadow mask welded portion provided on the side wall portion and the portion inclined inward, different, The mechanical strength of each side of the frame can be arbitrarily adjusted according to the length of each side and the tension of the shadow mask.

Further, the side wall portion is provided with a portion perpendicular to the shadow mask welding portion and a portion inclined inward and outward so as to be repeated continuously, and the ridge line of the side wall portion and the shadow mask welding portion is a straight line. By forming the ridge line between the and the flange portion into a corrugated shape, the frame body can be similarly integrally formed by press working, and the mechanical strength can be made uniform over almost the entire side wall portion. Further, in the vicinity of the boundary with the shadow mask welded portion, by making the cross section of the side wall portion parallel to the shadow mask substantially octagonal, a gap is formed between each corner portion of the shadow mask welded portion and the side wall portion. The shape of each corner of the shadow mask weld is stable during press working, and the flatness of the shadow mask weld can be maintained. Further, by making the thermal expansion coefficient of the material of the frame body smaller than the thermal expansion coefficient of the material of the shadow mask, the thermal capacity of the shadow mask and the frame body at the time of joining the glass funnel of the color cathode ray tube and the panel. It is possible to prevent plastic deformation of the shadow mask due to the difference.

[Brief description of drawings]

FIG. 1 is a sectional view showing a configuration of a preferred first embodiment of a color cathode ray tube of the present invention.

FIG. 2 is a perspective view showing a detailed configuration of a frame body 4 in the first embodiment.

FIG. 3 is a perspective view showing a detailed structure of a frame body 4 in a second preferred embodiment of the color cathode ray tube of the present invention.

4 (a), (b) and (c) are respectively AA cross section, BB cross section and C of the frame body 4 in the second embodiment.
-Figure showing a C cross section

[Explanation of symbols]

1: Funnel 2: Panel 3: Shadow mask 4: Frame 6: Neck part 7: Electron beam 8: Fluorescent surface 41: Shadow mask welded part 41a: Long side 41b: Short side 41c: Corner part 41d: Gap 42: Side wall Part 42a: a part perpendicular to the shadow mask welded part 42b: a part inclined inward with respect to the shadow mask welded part 42c: ridge line 42d: opening 43: flange part 45: side wall part 45a: ridge line 45b: ridge line

Claims (8)

[Claims] 1. A substantially rectangular frame-shaped shadow mask weld having continuous sides, and a portion which is continuously formed on the inner circumference of each side of the shadow mask weld and is perpendicular to the shadow mask weld. In a state in which a predetermined tension is applied, a frame body having side wall portions in which inclined portions are alternately provided, and a flange portion continuously formed on the side wall portions and parallel to the shadow mask welded portion, A color cathode ray tube comprising a shadow mask welded to a shadow mask welding surface of the frame body. 2. A slope line of the inclined portion of the side wall portion is substantially parallel to a side of the shadow mask weld portion, and the shadow mask weld portion provided on the side wall portion is on a plane perpendicular to the shadow mask. 2. The color cathode ray tube according to claim 1, wherein a substantially triangular opening is formed by a portion perpendicular to the above and an inclined portion and the flange portion. 3. At least one of the size and the number of a portion perpendicular to the shadow mask welding portion provided on the side wall portion and a portion inclined inward on the long side and the short side of the frame body. 3. The color cathode ray tube according to claim 1, wherein 4. A substantially rectangular frame-shaped shadow mask weld having continuous sides, and a portion which is continuously formed on the inner circumference of each side of the shadow mask weld and is perpendicular to the shadow mask weld. And a side wall portion that is provided so as to be repeatedly continuous with the portion that is inclined outward, and a frame body that has a flange portion that is continuously formed on the side wall portion and that is parallel to the shadow mask welded portion, and a predetermined tension A color cathode ray tube comprising a shadow mask welded to a shadow mask welding surface of the frame body in an applied state. 5. The color cathode ray tube according to claim 4, wherein the ridgeline of the side wall portion and the shadow mask welded portion is a straight line, and the ridgeline of the side wall portion and the flange portion is a wavy line. 6. The color cathode ray tube according to claim 1, wherein a cross section of the side wall portion parallel to the shadow mask in the vicinity of the boundary with the shadow mask welded portion is substantially octagonal. 7. The color cathode ray tube according to claim 1, wherein the frame body is integrally formed by press molding. 8. The thermal expansion coefficient of the material of the frame is smaller than the thermal expansion coefficient of the material of the shadow mask.
7. The color cathode ray tube according to any one of 1 to 7.