JPH1012153A - Color cathode ray tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a color cathode ray tube from the resonance and deformation of a shadow mask caused by shock applied especially in the tube axis direction from the outside. SOLUTION: The length (b) to a stud pin from the welding point 16a of one spring 13a for holding a mask frame 12 to a face panel 14 is made different from the length (a) in other springs 13b, 13c, 13d. Shock from the outside to a cathode ray tube is not transferred at the same time to the mask frame 12 from each spring, resonance of a shadow mask is prevented, and the brightness variation, generation of wave pattern, and deterioration of color purity on a screen are retarded.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a color cathode ray tube having an improved structure for supporting a shadow mask on a face panel.

[0002]

2. Description of the Related Art FIG. 3 is a plan view of an essential part for explaining an example of a conventional shadow mask support structure of a color cathode ray tube. The shadow mask 1 is fixed to a holding mask frame 2, and four springs 3a, 3b, 3c,
3d, the stud pins 5a, 5b, 5 of the face panel 4
c, 5d. That is, the shadow mask 1 is welded to the mask frame 2, and the springs 3a, 3b,
The other ends of 3c and 3d are stud pins 5a, 5b, 5c and 5
d, the shadow mask 1 is held in the face panel 4. As shown, the springs 3a, 3
welding points 6a, 6 between b, 3c, 3d and mask frame 2
b, 6c and 6d are located on each of the four sides of the mask frame 2, and the welding points 6a and 6a of the springs 3a, 3b, 3c and 3d.
6b, 6c, 6d to stud pins 5a, 5 at the other end.
The lengths of b, 5c and 5d are all equal.

[0003]

By the way, the above-mentioned conventional shadow mask supporting structure has the welding points 6a, 6b, 6 of the springs 3a, 3b, 3c, 3d shown in FIG.
c, 6d to other end stud pins 5a, 5b, 5
The lengths up to c and 5d are equal to each other. With this structure, when an impact is applied to the color cathode ray tube in the tube axis direction, the vibration is transmitted to the mask frame simultaneously and evenly through each stud pin and each spring. Resonance of the mask occurs. This makes it impossible for the electron beam emitted from the electron gun to always completely hit the desired phosphor, resulting in a change in luminance and an undesirable wavy pattern on the screen. Further, when the impact in the tube axis direction is further increased, the shadow mask is deformed due to the resonance of the shock wave, and there is a disadvantage that the luminance changes on the screen and the color purity deteriorates.

[0004]

SUMMARY OF THE INVENTION The present invention provides a shadow mask, a mask frame for holding the shadow mask, a spring having one end welded and fixed to the mask frame, and a spring embedded in the face panel. In a color cathode ray tube having a stud pin whose other end is fitted, at least one of the lengths from the position where the spring is fixedly welded to the mask frame to the other stud pin is different from other springs. It is composed of things.

According to the above construction, the impact in the tube axis direction on the color cathode ray tube is transmitted to the mask frame via each stud pin and each spring. At this time, only one spring has a different spring length. At the same time, it does not reach the mask frame. Due to this, the resonance of the mask frame due to the impact in the tube axis direction is suppressed,
Resonance and deformation of the shadow mask are suppressed. For this reason, it is possible to suppress a change in luminance and a wavy pattern on the screen and a deterioration in color purity.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 1 is a plan view of a main part of a color cathode ray tube according to one embodiment of the present invention. The shadow mask 11 is welded to the mask frame 12, and the springs 13a, 13
One ends of b, 13c and 13d are welded to the mask frame 12 at welding points 16a, 16b, 16c and 16d. The other ends of the springs 13a, 13b, 13c and 13d are connected to stud pins 15 embedded in the face panel 14.
a, 15b, 15c, and 15d, respectively. At this time, the spring 13a is connected to the other springs 13b, 13b.
The length from the welding point to the mask frame to the stud pin is longer than c and 13d (b> a in the drawing).

According to this embodiment, the impact on the color cathode ray tube in the tube axis direction is caused by the stud pins 15a, 15b, 1
5c, 15d and springs 13a, 13b, 13c, 1
It is transmitted to the mask frame 12 via 3d. However, the spring 13a is different from the other springs 13b, 13c,
Since the length is longer than 13d, the impact is not transmitted to the mask frame at the same time, so that the resonance of the shadow mask hardly occurs, and the deformation of the shadow mask due to the resonance hardly occurs. As a result, it is possible to prevent the deterioration of the brightness, the generation of a wavy pattern, and the deterioration of the color purity on the screen. Note that this effect is achieved by the other springs 13b, 13c, 13d
The same applies when the length from the welding point to the mask frame to the stud pin is shortened. Further, for example, by making the length of two adjacent springs longer or shorter than the other springs among the four springs, it is also possible to change the length to the stud pin at the welding point of the mask frame. An equivalent effect can be obtained.

FIG. 2 is a plan view of a main part of a color cathode ray tube according to a second embodiment of the present invention. This embodiment is different from the first embodiment in that four springs are used.
Since it is the same as the first embodiment except that it is constituted by three springs, the same parts are denoted by the same reference numerals and the description thereof will be omitted. The length of the spring 13a from the welding point to the mask frame to the stud pin is longer than that of the other springs 13b, 13c, and 13d (illustration b>).
a).

According to this embodiment, the impact of the color cathode ray tube in the direction of the tube axis is prevented by the spring frame 13a.
Since the length (b) from the welding point 16a to the stud pin 15a to the stud pin 15a is longer than the length (a) of the other two springs 13b and 13c, the impact is not transmitted to the mask frame 12 at the same time. For this reason, the same shadow mask resonance preventing effect as in the first embodiment can be obtained. Also, this effect is achieved by the fact that the springs 13a are
The same applies when the length from the welding point to the mask frame to the stud pin is shorter than c.

[0010]

As described above, according to the present invention, if the length from the welding point of the spring to the mask frame to the stud pin at the other end is made longer than that of the other springs by, for example, one, the length is different. Accordingly, it is possible to suppress the resonance of the shadow mask through the mask frame due to the impact on the color cathode ray tube. For this reason, it is possible to suppress a change in luminance and a wavy pattern caused by an impact on the color cathode ray tube, and a deterioration in color purity.

[Brief description of the drawings]

FIG. 1 is a plan view of a main part of a color cathode ray tube according to the present invention (Example 1).

FIG. 2 is a plan view of a main part of a color cathode ray tube according to the present invention (Example 2).

FIG. 3 is a main part plan view showing an example of a conventional color cathode ray tube.

[Explanation of symbols]

 11 Shadow Mask 12 Mask Frame 13a, 13b, 13c, 13d Spring 14 Face Panel 15a, 15b, 15c, 15d Stud Pin 16a, 16b, 16c, 16d Welding Point

Claims (5)

[Claims] A collar including a shadow mask, a mask frame for holding the shadow mask, a spring having one end welded and fixed to the mask frame, and a stud pin embedded inside the face panel and fitted with the other end of the spring. A color cathode ray tube, wherein at least one spring has a length different from that of another spring in a cathode ray tube in which a position where a spring is fixed by welding and a stud pin at the other end. 2. The color cathode ray tube according to claim 1, wherein the length between the position where the spring is fixed by welding and the stud pin at the other end is shortened by one of the four springs. . 3. The color cathode ray tube according to claim 1, wherein the length between the position where the spring is fixed by welding and the other end of the spring is increased by one of the four springs. . 4. The color cathode ray tube according to claim 1, wherein the length between the position where the spring is fixed by welding and the stud pin at the other end is shortened by one of the three springs. . 5. The color cathode ray tube according to claim 1, wherein the length between the position where the spring is fixed by welding and the stud pin at the other end is increased by one of the three springs. .