KR100395810B1 - Shadow mask frame assembly for color cathode ray tube - Google Patents

Abstract

PURPOSE: A shadow mask frame assembly is provided to achieve improved structural strength even when the aperture portion is flat, while preventing a doming phenomenon. CONSTITUTION: A shadow mask frame assembly comprises a shadow mask(60) including an aperture portion(61) having a plurality of electron beam passing holes, a non-aperture portion(62) extended from the edge of the aperture portion, and a skirt portion(63) bent from the non-aperture portion; and a frame(70) including a support(71) where the skirt portion is fixed. The non-aperture portion of the shadow mask has a radius of curvature smaller than the radius of curvature of the aperture portion of the shadow mask.

Description

Shadow Mask Frame Assembly for Color Cathode Ray Tube

The present invention relates to a color cathode ray tube, and more particularly, to a shadow mask frame assembly for accurately scanning a fluorescent film with an electron beam emitted from each electron gun mounted inside a panel.

In general, the color cathode ray tube is provided with a panel 10 having a fluorescent film 11 formed on an inner surface thereof, as shown in FIG. 1, and a shadow mask 21 provided to be spaced apart from the fluorescent film by a predetermined distance inside the panel 10. And a shadow mask frame assembly 20 composed of a frame 22 supporting the same, and an electron gun 40 enclosed in the neck portion 31 and deflected in the cone portion 32 to be sealed to the panel 10. It is comprised with the funnel 30 in which the oak 50 was installed.

As shown in FIG. 2, the shadow mask 21 having the color discriminating function includes a hole 21a having a plurality of electron beam through holes H and an open portion extending from an edge of the hole 21a. 21b and the skirt part 21c extended so that it may become perpendicular | vertical downward from the said non-hole part 21b. The frame 22 includes a support portion 22a on which the skirt portion 21c of the shadow mask 21 is welded and supported, and a flange portion 22b bent inwardly from the support portion 22a.

In the color cathode ray tube configured as described above, the electron beam emitted from the electron gun 40 mounted on the neck portion 31 is selectively deflected by the deflection yoke 50 so as to pass through the electron beam of the shadow mask 21 having a color selection function. It passes through the ball and lands at each fluorescent point of the fluorescent film 11 to form an image.

As described above, the electron beam that is emitted from the electron gun 40 and landed in the fluorescent film 11 to excite it, that is, the hot electrons, does not pass all of the electron beam passing holes H of the shadow mask and passes only about 15% by 30%. Therefore, the electron beam that does not pass through the electron beam passing hole (H) hits the perforations 21a of the shadow mask, thereby heating the shadow mask 21 and the frame 22 supporting the shadow mask 21, and further, the shadow mark 21. Doming phenomenon is caused.

The dominant phenomenon of the shadow mask 21 is that the position of the electron beam through hole H formed in the hole 21a of the shadow mask 21 is shifted so that the electron beam emitted from the electron gun 40 is accurately fluorescent film 11. There was a problem that can not be landing at the fluorescence point.

In order to solve such a problem, the shadow mask 21 is compensated by adjusting the Q value (gap between the fluorescent film and the shadow mask) by moving the shadow mask toward or away from the fluorescent film 11. A satisfactory effect could not be expected.

In addition, as the shadow mask is flattened recently, its structural strength is weak.

The present invention has been made to solve the above problems, and an object thereof is to provide a shadow mask frame assembly for a color cathode ray tube, which can prevent the doming phenomenon of a shadow mask heated by an electron beam emitted from an electron gun.

Another object of the present invention is to provide a shadow mask frame assembly for a color cathode ray tube that can prevent the structural strength of the shadow mask from being weakened as the pore is flattened.

1 is a cross-sectional view of a common color cathode ray tube,

2 is a partially cutaway perspective view showing an extract of a conventional shadow mask frame assembly;

Figure 3 is an exploded perspective view showing a shadow mask frame assembly according to the present invention.

4 is a cross-sectional view taken along the line A-A shown in FIG.

5 is a perspective view showing another embodiment of the shadow mask frame assembly according to the present invention;

FIG. 6 is a cross-sectional view taken along line A′-A ′ of FIG. 5;

<Description of reference numerals for main parts of the drawings>

60; Shadow mask 61; Perforation

62; No study 63; Skirt

70; Frame 71; Support (of frame)

80; bend

In order to achieve the above object, the present invention provides a shadow including a hole formed with a plurality of electron beam through holes and having a predetermined curvature, a non-hole extending at a predetermined angle from an edge of the hole and a skirt portion bent from the hole. A shadow mask frame assembly for a color cathode ray tube comprising a mask and a frame including a support portion to which the skirt is fixed, wherein the radius of curvature of the unperforated portion of the shadow mask is smaller than the radius of curvature of the perforated portion. It is done.

In the present invention, the bent portion due to the difference in curvature is formed at the boundary between the hole portion and the non-hole portion.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The shadow mask frame assembly for a color cathode ray tube according to the present invention has a shadow mask 60 and a frame 70 coupled to each other, as shown in FIGS. 3 to 6, and installed inside the panel to have a color selection function.

The shadow mask 60 includes a hole 61 in which a plurality of electron beam passing holes H are formed in a predetermined pattern, a hole 62 extending from the hole 61, and the hole 62. ) And a skirt portion 63 extending downward. The radius of curvature of the non-pores 62 is smaller than the radius of curvature of the perforations 61. That is, the curvature R2 of the pore 61 is smaller than the curvature R1 of the non-porous portion 62.

The bent portion 80 is formed at the boundary between the perforated portion 61 and the unperforated portion 62 of the shadow mask 60 by the difference in curvature, and the bent portion 80 is formed stepwise. In more detail, the bent portion 80 is bent downward or bent upwards at the boundary of the non-perforated portion 62 to provide a connection portion 81, and a hole 61 at the end of the connection portion 81. Is connected with the edge of the. As a result, when the connecting portion 81 is bent downward, the perforated portion 61 of the shadow mask is positioned below the upper surface of the non-boiling portion 62, and when the connecting portion 81 is bent upward, Studying 61 is located above the upper surface of the non-welding portion 62. In addition, the beads 64 are formed in the air holes 62 and 62 '.

The frame 70 supporting the shadow mask includes a support portion 71 coupled to the skirt portion 63.

The shadow mask frame assembly for a color cathode ray tube according to the present invention configured as described above has a structural strength of the shadow mask 60 because the radius of curvature of the non-perforated part 62 of the shadow mask is smaller than the radius of curvature of the perforated part 61. Can improve. In more detail, as the screen surface of the cathode ray tube is planarized recently to prevent distortion of the image due to the curvature, the curvature of the perforations of the shadow mask becomes smaller, so that the structural strength of the shadow mask is relatively weak. Since the radius of curvature of the non-perforations is smaller than the radius of curvature of the perforations 61, the support force of the perforations 61 by the non-perforations 62 increases, thereby preventing the strength of the shadow mask from weakening. have. That is, the bent portion 80 is formed by the difference in curvature at the boundary portion between the perforated portion 61 and the non-perforated portion 62, and the bent portion 80 is the non-perforated portion 61 and the non-perforated portion 62. It includes a connection portion 81 formed perpendicular to the boundary of. The connecting portion 81 is formed so that the upper and lower edge portions have an ellipse by the curvature of the non-perforated portion and the curvature of the perforated portion, thereby preventing the perforated portion from sagging with respect to the non-perforated portion.

In addition, the shadow mask is heated and thermally expanded by hot electrons that do not pass through the electron beam passing hole H formed in the hole 61, and the amount of thermal expansion is connected to the hole 61 and the hole 62. 81 is absorbed by bending in the radial direction with respect to the non-perforation and the perforation.

The shadow mask frame assembly according to the present invention operated as described above has the following effects.

first; As the hole is flattened, the curvature of the hole is increased to prevent structural weakening due to the decrease in the curvature of the hole.

second; The thermal expansion amounts of the perforated portions and the unperforated portions of the shadow mask are absorbed by bending the connecting portions formed at the boundary portions thereof.

third; The connecting portion formed stepped from the non-perforated portion serves as a spring for supporting the edge of the shadow mask to prevent the perforation portion from sagging.

fourth; It is possible to prevent the movement of the electron beam through hole formed in the perforation part by preventing the dominant phenomenon of the shadow mask.

Although the present invention has been described with reference to one embodiment shown in the drawings, this is merely exemplary and those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. Therefore, the true scope of the present invention will be defined by the technical spirit described in the claims.

Claims (4)

A shadow mask including a hole having a plurality of electron beam through holes and having a predetermined curvature, a non-hole extending at an angle from an edge of the hole, and a skirt bent from the hole, and a support portion to which the skirt is fixed. In the shadow mask frame assembly for a color cathode ray tube comprising a frame comprising: The shadow mask frame assembly for a color cathode ray tube, characterized in that the curvature radius of the non-perforated portion of the shadow mask is smaller than the curvature radius of the perforated portion. The shadow mask frame assembly for color cathode ray tubes according to claim 1, wherein a bent portion is formed by a difference in curvature at a boundary portion between the perforated portion and the unperforated portion. The shadow mask frame for color cathode ray tube of claim 2, wherein the bent portion is formed at a right angle with respect to the perforated portion, and the upper and lower surfaces include a connecting portion connecting the edge of the perforated portion and the edge of the non-perforated portion, respectively. Assembly. The shadow mask frame assembly for color cathode ray tubes according to claim 1, wherein beads are formed in the air holes.