KR20000051451A - Shadowmask-frame assembly of flat CRT - Google Patents

Abstract

PURPOSE: A shadow mask frame assembly of a flat cathode ray tube is provided which can improve the productivity with a simple fabrication process and can exclude the effect of the earth magnetic field. CONSTITUTION: A shadow mask frame assembly(100) of a flat cathode ray tube includes; a frame(110) including a pair of support members(111,112) having a first supporting part(111a,112a) and a first reinforcement part(111b,112b) prolonged from the first supporting part with an angle, and a pair of elastic members(113,114) which have a second supporting part(113a,114a) and a reinforcement part(113b,114b) prolonged from the second supporting part with an angle, and support one side ends and another side ends of the support member: and a shadow mask(120) supported by the frame. The end parts of the first and second supporting part are located on the same plane, and at least more than one notch part is formed in the center of the second supporting part.

Description

Shadowmask frame assembly of flat cathode ray tube

The present invention relates to a planar cathode ray tube, and more particularly, to a shadow mask frame assembly of a planar cathode ray tube supporting a shadow mask.

The color cathode ray tube has a color discrimination function. The color cathode ray tube excites the fluorescent film by landing on the fluorescent film through an electron beam through hole of a shadow mask which is spaced apart from the fluorescent film by a predetermined distance, thereby forming an image. .

The screen surface of the conventional color cathode ray tube which forms an image as described above is designed to have a predetermined curvature in consideration of the deflection trajectory of the electron beam when the electron beam emitted from the electron gun is deflected by the deflection yoke. Therefore, the shadow mask is designed to have a curvature corresponding to the curvature of the screen surface.

In such a conventional cathode ray tube, the shadow mask is heated by an electron beam, that is, hot electrons emitted from the electron gun, and a domming phenomenon that swells to the panel side occurs. This doming phenomenon causes the electron beam not to land on the fluorescent film correctly. In addition, the screen surface is formed to have a predetermined curvature, thereby narrowing the viewing angle and distorting the image formed by excitation of the fluorescent film at the edge of the screen surface.

In order to solve the problems described above, a planar cathode ray tube having a flat screen has been developed. The planar cathode ray tube forms a panel on which a fluorescent film is formed in a flat plate shape, and is fixed to an inner surface of the panel so as to be spaced apart from the fluorescent film formed on the inner surface of the panel by a predetermined tension while a predetermined tensile force is applied to the shadow mask. In this state, the panel is sealed with a funnel equipped with an electron gun and a deflection yoke.

In such a flat cathode ray tube, a support structure of a tension mask for a flat panel is disclosed in US Pat. No. 4,900,977. A support band is mounted on a panel formed with a sealing portion along an edge thereof, At the end, a tension mask is mounted.

As described above, fixing the shadow mask to the panel should form a stepped sealing at the edge of the panel, and the gap between the shadow mask and the fluorescent film formed on the inner surface of the panel according to the mounting state of the support band to the panel (hereinafter referred to as Q). Abbreviation) is severe.

In order to solve this problem, a method of fixing a shadow mask to a separate frame mounted inside the panel has been proposed. An example of such a shadow mask frame assembly is shown in FIG.

As shown, a frame 10 having support members 11 and 12 installed in parallel with each other, and elastic members 13 and 14 having elasticity and interconnecting the support members 11 and 12. And a flat shadow mask 20 in which upper and lower edges are welded so that tension is applied to the support members 11 and 12, and slots on the stripe are formed.

The shadow mask frame assembly may be configured to allow the support member (11) (12) and the elastic member (13) (14) to take into account the cross-sectional secondary moment of the support members (11) and (12). Since the cross section needs to be determined, there are many limitations in determining the cross-sectional shape of each member. In particular, the structure as described above has a heavy weight problem.

Figure 2 shows the structure of a conventional rectangular integrated frame.

As shown in the drawing, the long side portions 31 and 31 and the short side portions 32 and 32 are formed in a lattice shape. Cross sections of the long side portions 31 and 31 and the short side portions 32 and 32 are formed in an L-shape, and the heights of the short side portions 32 and 32 are of the long side portions 31 and 31. It is formed lower than the height.

Since the long side portions 31 and 31 and the short side portions 32 and 32 are integrally formed, such a frame is not easily manufactured to have sufficient structural strength, and the height of the short side portions 32 and 32 is low. Since it is formed, there is a problem that the earth's magnetic field penetrates. In addition, the integrated frame is produced by press working, a large capacity press equipment is required to produce a frame having sufficient structural strength.

The present invention is to solve the above problems, it is easy to manufacture and can exclude the influence of the geomagnetic field, and to provide a shadow mask frame assembly of a flat-type cathode ray tube that can improve the productivity by simple manufacturing There is a purpose.

1 is a perspective view showing an example of a shadow mask support frame of a conventional flat cathode ray tube;

Figure 2 is a perspective view of another example of the shadow mask support frame of the conventional flat cathode ray tube,

3 is an exploded perspective view of a shadow mask frame assembly of a planar cathode ray tube according to the present invention;

4 is an enlarged perspective view illustrating a state in which the support member and the elastic member are coupled to each other;

5 and 6 are side views showing a state in which the frame is elastically deformed,

Figure 7 is a perspective view showing another embodiment of the shadow mask frame assembly of the planar cathode ray tube according to the present invention.

<Brief description of symbols for the main parts of the drawings>

111,112; Support member

111a, 112a; First support portions 111b and 112b; First reinforcement department

113,114; Elastic member

113a, 114a; Second support portions 113b and 114b; Second reinforcement department

120; Shadow mask

In order to achieve the above object, the shadow mask support frame of the planar cathode ray tube includes a pair of support members each having a first support portion and a first reinforcement portion extending at a predetermined angle from the first support portion;

And a pair of elastic members each having a second support portion and a second reinforcement portion extending from the second support portion at a predetermined angle to support one end portion and the other end portion of the support member, respectively. do.

In the present invention, the end portions of the first and second support portions are positioned on the same plane, and the elastic member may have a predetermined single curvature or may be formed in a wave shape. The notch part may be formed at the center of the second support part of the elastic member to facilitate bending when the shadow mask is mounted.

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

A flat cathode ray tube is formed by enclosing a panel having a flat screen, and a funnel having an electron gun and a deflection yoke installed in the neck portion and the cone portion, respectively. A fluorescent film is formed on the inner surface of the screen of the panel. Inside the cathode ray tube, a frame supporting a shadow mask for accurately landing the electron beam emitted from the electron gun at each fluorescent point of the fluorescent film is installed.

3 and 4 show one embodiment of a shadowmask frame assembly with a frame according to the present invention.

As shown in the drawing, the shadow mask frame assembly 100 includes a frame 110 on a lattice and a shadow mask 120 fixed in a state in which a predetermined tensile force is applied to the frame 110.

The slop-shaped frame 110 forms a long side portion and includes reinforcing portions 111b and 112b extending at predetermined angles from the lower ends of the first supporting portions 111a and 112a and the first supporting portions 111a and 112a. Branch having a pair of support members 111 and 112, and a short side portion of the frame, extending from the ends of the second support portions 113a and 114a and the second support portions 113a and 114a at a predetermined angle. And a pair of elastic members 113 and 114 having second reinforcing parts 113b and 114b, each end of which is fixed to both ends of the support member.

As shown in FIG. 4, the end portions of the support members 111 and 112 forming the long sides and the elastic members 113 and 114 are coupled to each other by the first reinforcement 111b of the support members 111 and 112 ( 112b) and the second reinforcing portions 113a and 114a of the elastic members 113 and 114 are welded to each other. In this way, the first support portions 111a and 112a of the support members 111 and 112 and the second support portions 113a and 114a of the elastic members 113 and 114 are not contacted with each other and are spaced apart from each other by a predetermined interval. It is preferable to install it. The first reinforcing part and the second reinforcing part may be combined by welding or by using a fastening means such as a separate bolt nut. When the pair of support members 111 and 112 and the elastic member 113 and 114 are coupled, the positions of the first support portions 111a and 112a and the second support portions 113a and 114a are located on the same plane. do. That is, the heights of the end portions of the first and second supporting parts are the same from the lower surface of the frame.

In addition, the elastic members 113 and 114 are bent or wave-shaped to have a single curvature as shown in FIGS. 5 and 6. The bending of the elastic members 113 and 114 is not limited by the above-described embodiments, and any shape may be easily deformed within the elastic range of the elastic members 113 and 114 when the shadow mask is to be described later. It is possible or not.

In addition, notches 113c and 114c are formed at the centers of the elastic members 113 and 114, that is, the centers in the longitudinal direction to smooth the bending when the shadow mask is mounted. The notches 113c and 114c are described as being installed at the central portion in the longitudinal direction, but may be formed at positions spaced apart from the central portion at equal intervals. Bimetals 115 for preventing an excessive tensile force from being applied to the shadow mask due to thermal expansion of the elastic members 113 and 114 and thermal expansion of the support members 111 and 112 on the lower surfaces of the elastic members 113 and 114. ) Can be installed. The bimetals 115 are installed to move the support members 111 and 112 in mutually opposite directions during thermal expansion.

A shadow mask is supported on the frame configured as described above, and the shadow mask is supported by the first and second support parts 111a and 112a of the frame so that a predetermined tensile force is applied. The shadow mask 120 is formed with a slot 121 through which the electron beam passes by a plurality of strips 122 spaced apart from each other by a predetermined interval.

Another embodiment of the shadow mask further includes tie bars 123 interconnecting adjacent strips 122 across the slots 121, as shown in FIG. In this case, it is preferable that a portion of the short side of the shadow mask is supported by the second support parts 113a and 114a.

The shadow mask support frame of the flat cathode ray tube constructed as described above is coupled to the support members 111 and 112 constituting the long side and each end of the elastic members 113 and 114 constituting the short side. Simple and easy to manufacture In particular, when the shadow mask 120 is fixed to the frame 110, the upper and lower edges are welded while the shadow mask 120 is thermally expanded, so that a tensile force is applied to the shadow mask during cooling. In this process, the support members 111 and 112 of the frame 100 receive a movement force in a direction opposite to each other, and the movement force is absorbed by the elastic deformation force of the elastic members 113 and 114. In the process of absorbing the elastic deformation force, as shown in FIGS. 5 and 6, notch portions 113c and 114c are formed in the first and second support portions of the elastic members 113 and 114, or the elastic members are wavy. Since it is formed, it is possible to prevent the elastic member from being abnormally deformed by the notches 113c and 114c when bending.

In addition, when the elastic member is bent at a single curvature, the bending direction is determined by the bending force of the shadow mask 120 supported by the support members 111 and 112, and thus the bending is easily performed. Excessive tensile force can be prevented from being applied.

In addition, as shown in FIG. 7, since the strips are interconnected by the tie bars 123 to partition the slits, the mask is prevented from vibrating by an impact applied from the outside, and particularly, the short side of the shadow mask is elastic. Since it is supported by the 2nd support part 113a, 114a of the member 113, 114, it can prevent that the edge of a short side part is bent by the tension applied to the long side part direction.

The shadow mask frame assembly of the planar cathode ray tube according to the present invention configured as described above is easy to elastically deform the elastic member, and can surround the perforations of the shadow mask by the first and second supports, thereby reducing the influence of the earth's magnetic field. . In addition, since the cross-sections of the support member and the elastic member have the same shape, the production is simple and the productivity can be improved during production.

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 variations are possible from this. Therefore, the present invention will be defined by the technical spirit of the appended claims the true technical protection scope of the present invention.

Claims (6)

A pair of support members each having a first support portion and a first reinforcement portion extending at a predetermined angle from the first support portion; And a pair of elastic members each having a second support portion and a reinforcement portion extending from the second support portion at a predetermined angle and connecting one end portions and the other end portions of the support member, respectively. Shadow mask supported on the frame: Shadow mask frame assembly of the planar cathode ray tube comprising a. 2. The shadow mask frame assembly of claim 1, wherein the ends of the first and second supports are located on the same plane. The method of claim 1, The shadow member frame assembly of the planar cathode ray tube, characterized in that the elastic member has a predetermined single curvature or formed in a waveform. The method according to claim 1 or 2, The shadow mask frame assembly of the planar cathode ray tube, characterized in that at least one notch is formed in the center of the second support. The method of claim 1, The shadow mask frame assembly of the planar cathode ray tube, characterized in that the long side portion of the shadow mask is supported on the first support. The method of claim 5, A shadow mask frame assembly of a planar cathode ray tube, characterized in that a portion of the shadow mask short side portion is supported on the second supports.