KR20000073437A - Mask and frame Assembly for color CRT - Google Patents

Abstract

PURPOSE: A mask frame structure for a color cathode ray tube is provided in which adhesion between a frame and a shadow mask is improved to increase thermal conduction performance and reduce vibrations. CONSTITUTION: In a color cathode ray tube including a shadow mask(70) having a top surface in which countlessly large number of holes and a skirt(70a) bent from the top surface, a side wall(80a) to which the skirt is welded, and a bottom(80b) bent toward the inside thereof from the side wall, the skirt is bent toward the end of the side wall to be sloped at a predetermined obtuse angle on the basis of the bottom. The side wall is sloped at an obtuse angle larger than the slope of the skirt on the basis of the bottom. The angle(Q1) between the skirt and the bottom is in the range of 95-120 degrees. The angle(Q2) between the side wall and the bottom is in the range of 95-130 degrees.

Description

Mask frame structure for color cathode ray tube {Mask and frame Assembly for color CRT}

The present invention relates to a color cathode ray tube, and more particularly, to a mask frame structure for a color cathode ray tube for improving adhesion between a frame and a shadow mask to obtain an effect of improving heat conduction performance and reducing vibration.

As is well known, color cathode ray tubes are the most widely used display devices for observation of oscilloscopes and radars as well as television receivers.

The color cathode ray tube includes red, green, and blue phosphor pixels having three primary color emission spectra of light, which is an all-optical device that converts image information received as an electrical signal into visual information, graphite as a light absorbing material, and It is a device that plays the role of delivering color images to human vision through fluorescent film made of aluminum film for improving brightness.

1 illustrates a general color cathode ray tube.

As shown in the figure, a funnel-shaped funnel 2 fused to the rear end of the panel 1 forms a vacuum outer container, and the end of the diameter of the funnel 2 is small, that is, the neck portion 3. The electron gun 5 which radiates the electron beam 4 is enclosed with the inside.

A fluorescent film 6 is formed on the inner surface of the panel 1, and a shadow mask 7, which serves as a color screening function of the electron beam 4, is supported by the frame 8 to be rearward a predetermined distance from the fluorescent film 6. The deflection yoke 9 which is spaced apart and provided and which produces a pincushion type horizontal deflection magnetic field and a barrel type vertical deflection magnetic field is attached to the outer side of the neck part 3 vicinity.

In this state, the electron beam 4 emitted from the electron gun 5 is deflected to the desired portion of the screen by the vertical and horizontal deflection magnetic fields of the deflection yoke 9, and passes through the shadow mask 7 so as to perform color screening. When the fluorescent film 6 is blown to generate visible light, and the visible light is emitted to the outside through the panel 1, the image can be recognized.

Therefore, in order to realize vivid colors, the position of the shadow mask 7 having the color discriminating function of the electron beam 4 should be maintained stably, and in this respect, the support between the shadow mask 7 and the frame 8 is very important. Do.

FIG. 2 schematically shows a shadow mask 7 which serves as color screening of the electron beam 4, in which a pair of long and short side skirt portions 7b and 7c are successively connected at the top surface 7a having a plurality of openings. On the top surface 7a, the corners of each skirt portion 7b and 7c, and the skirt portions 7b and 7c, beads 7d for structural strength improvement are formed, and formability is improved. For this reason, the skirt hole 7e is formed in each skirt part 7b and 7c, and the corner hole 7f is formed in the corner part which abuts each skirt part 7b and 7c.

FIG. 3 shows a frame 8 supporting the shadow mask 7, which comprises a pair of long side portions 8a and a pair of short side portions 8b, each of which has a long side portion 8a and a short side portion ( 8b) is a cross-sectional view of the side wall portion 8c to which the skirt portions 7b and 7c of the shadow mask 7 are welded to the inner side in a cross section, and is bent and formed in a substantially rightward direction inwardly from the side wall portion 8c. And a bottom portion 8d having a large opening 8e through which the electron beam 4 passes.

Here, having the bottom portion 8d in the frame 8 prevents all the electron beams 4 passing through the ends thereof from entering the side wall portion 8c so that the unnecessary fluorescent film 6 due to the rereflection of the electron beam 4 is caused. ) This is to prevent hitting, that is, the halation phenomenon.

On the other hand, the shadow mask 7 is formed by a mold in a flat mask state and has a top surface 7a having a constant curvature, and a pair of long / short side skirt portions 7b and 7c extending at right angles from the top surface 7a. A pair of long / short side skirt portions 7b and 7c are welded inside the side wall portion 8c of the frame 8 to maintain its shape.

However, in general, the metal has an inherent elastic force to return to its original shape, that is, a metal back phenomenon occurs. Since the shadow mask is also made of a metal material, each skirt part is not formed in a right angle direction and is illustrated in FIG. 4. As shown in the drawing, the spreading amount d is about 0.5 to 3.0 mm.

On the other hand, since the side wall portion of the frame is perpendicular to the bottom portion, even if each skirt portion of the shadow mask is in close contact with the inside of the side wall portion of the frame for welding, the shadow mask is not completely adhered by the skirt opening phenomenon and has a gap of about w. .

In this state, the lower end of the skirt of the shadow mask and the side wall of the frame are welded, so that only the bottom of the weld spot is in close contact after the welding, and the end of the skirt of the shadow mask is not completely in contact with the side wall of the frame.

As a result, heat generated from the shadow mask due to the electron beam strike cannot be easily transferred to the frame side, resulting in deterioration of color purity due to excessive thermal expansion of the shadow mask, and delaying the time to stabilize the initial screen of the product. It causes the deterioration of quality.

In addition, since the shadow mask and the frame are not completely in contact with each other, the shadow mask easily vibrates when an external impact occurs.

Accordingly, the present invention has been proposed in view of this point, and the shadow mask and the frame are welded in close contact with each other so that the heat generated from the shadow mask by the collision of the electron beam can be easily transferred to the frame side and the external impact. It is an object of the present invention to provide a mask frame structure for a color cathode ray tube which reduces vibration of a shadow mask.

1 is a configuration diagram of a general color cathode ray tube,

2 is a schematic diagram of a general shadow mask,

3 is a block diagram of a conventional frame,

3a is a plan view,

3b is a side view,

3C is a sectional view,

4 is a structural diagram of a combination of a conventional shadow mask and a frame,

5 is a coupling structure diagram of a shadow mask and a frame according to the present invention,

6 is an exemplary diagram in a case where an inclination angle of the skirt portion of the shadow mask is larger than an inclination angle of the side wall portion of the frame.

*** Explanation of symbols for main parts of drawing ***

70: shadow mask 70a: skirt portion

80: frame 80a: side wall portion

80b: Bottom part Q1: Angle formed by a skirt part and a bottom part

Q2: Angle formed by side wall and bottom

The mask frame structure for a color cathode ray tube according to the present invention for achieving the above object includes a shadow mask having a top surface through which numerous holes are opened and a skirt portion that is bent consecutively from the top surface, a side wall portion on which the skirt portion is welded, and the A color cathode ray tube comprising a frame having a bottom portion which is bent inwardly from a side wall portion, wherein the skirt portion is bent in an end direction of the side wall portion and inclined at a predetermined obtuse angle with respect to the bottom portion; The side wall portion may be inclined at an obtuse angle greater than or equal to the slope of the skirt portion with respect to the bottom portion.

Preferably, the angle formed by the skirt portion and the bottom portion is characterized in that it is in the range of 95 ° ~ 120 °.

Preferably, the angle formed by the side wall portion and the bottom portion is characterized in that in the range of 95 ° ~ 130 °.

In this way, the skirt portion of the shadow mask has an inclination similar to that of the side wall of the frame. When the shadow mask is inserted into the frame for welding, the entire surface of the skirt portion can be completely in contact with the side wall. The skirt portion can be firmly supported in a state of being completely in contact with the side wall portion of the frame.

And, there may be a plurality of embodiments of the present invention, hereinafter will be described in detail with respect to the most preferred embodiment.

This preferred embodiment allows for a better understanding of the objects, features and advantages of the present invention.

Hereinafter, exemplary embodiments of a mask frame structure for a color cathode ray tube according to the present invention will be described in detail with reference to the accompanying drawings.

In addition, in the drawing used for description, about the component same as FIG. 1 thru | or 4, the same code | symbol may be attached | subjected, and the overlapping description may be abbreviate | omitted.

In the coupling structure of the shadow mask 70 and the frame 80 according to the present embodiment, the skirt portion 70a of the shadow mask 70 is welded to and supported by the side wall portion 80a of the frame 80 as shown in FIG. 5. As a structure, the skirt portion 70a of the shadow mask 70 is a sidewall of the frame 80 to improve the adhesion between the skirt portion 70a of the shadow mask 70 and the sidewall portion 80a of the frame 80. It is bent in the direction of the end portion 80a and forms an obtuse angle with the bottom portion 80b of the frame 80, and the sidewall portion 80a of the frame 80 is also a shadow mask 70 based on the bottom portion 80b. It is formed to have an obtuse angle similar to the skirt portion 70a of the angle, the angle is at least the angle formed by the skirt portion 70a of the shadow mask 70 and the bottom portion 80b of the frame 80.

Referring to the operation of the present invention configured as described above is as follows.

First, in forming the skirt portion 70a of the shadow mask 70, when it is bent downward as in the prior art, the shadow mask 70 is opened in a direction perpendicular to the tube axis by a metal back phenomenon of a general metal, such as the shape of the shadow mask 70 In order to improve the adhesion between the shadow mask 70 and the frame 80 in the state of maintaining the side wall portion 80a of the frame 80 should be formed at an acute angle with respect to the bottom surface portion 80b.

However, when the side wall portion 80a of the frame 80 is formed at an acute angle with respect to the bottom portion 80b as described above, the electron beam strikes and reflects the side wall portion 80a of the frame 80 to unnecessarily form a fluorescent film. A halation phenomenon causing light emission is caused, and when the length of the bottom portion 80b is long to prevent such a halation phenomenon, there is a problem in that an effective screen cannot be secured.

Therefore, the skirt portion 70a of the shadow mask 70 is bent and formed in the upper direction as opposed to the conventional structure, and the skirt portion 70a of the shadow mask 70 is formed on the bottom portion of the frame 80 during molding. 80b) is formed in a direction perpendicular to the original direction, but is opened in the original position by the metal back phenomenon of the general metal, the inclination angle (Q1) is 95 ° ~ to the base portion 80b of the frame 80 It is about 120 °.

On the other hand, in order to improve the adhesion between the shadow mask 70 and the frame 80, the side wall portion 80a of the frame 80 should match the shape of the skirt portion 70a of the shadow mask 70, and thus the frame The side wall portion 80a of the 80 is formed to have an inclination angle Q2 similar to the inclination angle Q1 of the skirt portion 70a of the shadow mask 70, and the inclination angle Q2 of the side wall portion 80a is at least. The adhesion between the two members can be improved only if the angle of inclination Q1 of the skirt 70a is equal to or greater, and the skirt 70a of the shadow mask 70 is pushed toward the side wall portion 80a of the frame 80 at the welding point. Since no deformation occurs in the shadow mask 70, the size should be at least about 95 ° to about 130 °.

If the inclination angle Q2 of the side wall portion 80a of the frame 80 is smaller than the inclination angle Q1 of the skirt portion 70a of the shadow mask 70, as shown in FIG. 6, the two members may not be in close contact with each other. When the skirt portion 70a of the shadow mask 70 is pushed in the direction of the side wall portion 80a of the frame 80 for welding, the shadow mask 70 is not only deformed as in the related art, but also the shadow of the shadow mask 70 There is a constant distance between the skirt portion 70a and the side wall portion 80a of the frame 80, thereby exhibiting the same problem as the coupling structure of the mask frame according to the prior art.

Subsequently, welding is performed at a plurality of points while the skirt portion 70a of the shadow mask 70 is in close contact with the side wall portion 80a of the frame 80. When the welding is finished, the skirt portion of the shadow mask 70 is finished. The 70a is supported in a state of being fully in contact with the sidewall portion 80a of the frame 80, and at this time, the inclination angle of the skirt portion 70a and the inclination angle of the sidewall portion 80a become substantially the same.

As such, when the skirt portion 70a of the shadow mask 70 and the side wall portion 80a of the frame 80 are in close contact with each other, heat generated from the shadow mask 70 due to the electron beam collision is easily moved toward the frame 80. Since the stabilization time of the initial operation screen can be shortened and the shadow mask 70 is firmly supported by the frame 80, the vibration of the shadow mask 70 due to external vibration or impact can be reduced, thereby reducing the color purity. It can prevent deterioration.

In addition, although specific embodiments of the present invention have been described and illustrated above, it is obvious that the present invention may be variously modified and implemented by those skilled in the art.

Such modified embodiments should not be individually understood from the technical spirit or the prospect of the present invention, and such modified embodiments should fall within the appended claims of the present invention.

It is clear from the above description that, according to the present invention, the skirt portion of the shadow mask and the side wall portion of the frame are tightly adhered to each other to prevent deformation of the shadow mask during welding of the shadow mask and the frame, and heat generated from the shadow mask is easily transferred to the frame side. It is inverted to shorten the stabilization time of the initial screen operation, and the effect of reducing the vibration of the shadow mask due to external vibration or impact.

Claims (3)

A color cathode ray tube including a shadow mask having a top surface with numerous openings and a skirt portion bent continuously from the top surface, a sidewall portion to which the skirt portion is welded, and a frame having a bottom portion bent inward from the sidewall portion. In: The skirt portion, Bent toward the end of the side wall portion and inclined at a predetermined obtuse angle with respect to the bottom portion; The side wall portion, Mask frame structure for a color cathode ray tube, characterized in that inclined at an obtuse angle of at least the slope of the skirt portion relative to the bottom portion. The method of claim 1, And an angle formed by the skirt portion and the bottom portion is in a range of 95 ° to 120 °. The method of claim 1, And the angle formed by the side wall portion and the bottom portion is in the range of 95 ° to 130 °.