KR100307157B1 - Mask assembly of crt and assemble method thereof - Google Patents

Abstract

PURPOSE: A mask assembly of a CRT and an assemble method thereof are provided to cause a plurality of shadow masks to have through holes in the same position without forming a curvature or applying tension to the shadow mask. CONSTITUTION: A plurality of through holes are formed in a center of a shadow mask(1), which both ends are bent in a direction opposite to a plane. A frame(7) has two long sides(7a) and two short sides(7b) opposing each other about a hole through which an electron beam is irradiated. For this structure, in a semi press process, a hole part(3) of the shadow mask is planarized and both ends of the shadow mask are vertically bent. Then, the shadow mask(1) formed in the semi press process is fixed to the frame having a predetermined curvature.

Description

Mask assembly of cathode ray tube and its assembly method

The present invention relates to a mask assembly of a cathode ray tube and a method of assembling the same, and more particularly, to a mask assembly and a method of assembling an improved method of assembling a shadow mask and a frame.

In general, a cathode ray tube is a device that reproduces an image by emitting a phosphor by an electron beam controlled by an image signal. A fluorescent surface coated with three colors of red, green, and blue phosphors, a shadow mask having a color discrimination function, and an electron gun that emits an electron beam And a deflection yoke for scanning the electron beam on the fluorescent surface.

The color masking function of the shadow mask refers to the action of landing three lines of electron beams emitted from the electron gun with the corresponding phosphors of red, green, and blue colors. A shadow mask having such a function passes hundreds of thousands of electron beams. The perforations, through which the balls are drilled, the perforations forming the periphery of the perforations, and the perforations again include perimeters bent in the opposite direction of the perimeter and the panel.

In addition, the shadow mask is formed to have a corresponding curvature according to the shape of the corresponding panel, that is, the vertical and horizontal curvature of the panel, and in the case where the vertical and horizontal curvature is infinite so that the perforated part is formed flat, other shadows Unlike masks, it is common not to form a circumferential surface.

Shadow masks with infinite vertical and horizontal curvatures are generally called tension masks because they provide tension in all directions.

On the other hand, a typical shadow mask has a circumference fixed to a frame provided with suspension springs on each side to form a mask assembly, and the suspension spring is fitted to the stud pins fused to the inner surface of the panel to suspend the mask assembly in the inner space of the panel. .

As described above, the shaping of the shadow mask for forming the mask assembly and the assembling of the molded shadow mask and the frame are as follows.

First, in the case of a general shadow mask, that is, a shadow mask provided with a predetermined curvature in the perforated part, the perforated part having a predetermined horizontal and vertical curvature is formed by using a punch, a pad, and a die, and at the same time, the periphery is formed. The periphery of the completed shadow mask is welded to the side of the frame, and in the case of the tension mask, the unwelded part is welded to the frame with a predetermined tensile force applied in both or all directions.

However, in the general shadow mask forming process as described above, the shadow mask is compressed to a relatively high pressure and is stretched in all directions by this pressure, which causes the position of the through-holes drilled in a predetermined pattern throughout the perforations to be irregular in each direction. Of course, there is a drawback that defects such as spring back or uneven curvature are likely to occur due to unbalance of stress.

This is no exception in the case of a cylindrical shadow mask in which only the horizontal curvature has a predetermined value.

On the other hand, the tension mask has a disadvantage in that the process of fixing the frame in a state in which tension is applied from all directions requires high technical skills and the through hole position of the tension mask is irregular due to this tension.

Therefore, the present invention has been invented to solve the technical problem that the prior art did not solve, the object of the present invention does not need to form a curvature or tension on the shadow mask, so that many shadow masks of the same through-hole It is to provide a mask assembly that can have a position and a method of assembling the same.

A mask assembly for realizing the above object of the present invention comprises: a shadow mask having a plurality of electron beam through holes formed in a flat central portion, and at least both short edge portions bent in opposite directions of the panel; It includes a frame having two long sides and a short side facing each other with respect to the hole through which the electron beam passes, and fixed to the shadow mask and providing a predetermined curvature.

In addition, the method of manufacturing a mask assembly according to the present invention comprises a semi-pressing process of flattening the perforations of the shadow mask and simultaneously bending at least the ends of both short sides vertically; And an assembly process of fixing the shadow mask formed by the semi-press process to a frame having a predetermined curvature.

1 is an exploded perspective view of a shadow mask and a frame according to an embodiment of the present invention.

FIG. 2 is a perspective view of a mask assembly in which the shadow mask and the frame of FIG. 1 are assembled; FIG.

3 is a perspective view showing another shadow mask assembled to the frame shown in FIG.

4A to 4D are process diagrams illustrating a semipress process for molding the shadow mask shown in FIG. 1 or 3.

FIG. 5 is a perspective view illustrating another frame in which the shadow mask of FIG. 1 is assembled. FIG.

6 is a perspective view of a mask assembly in which the frame of FIG. 5 and the shadow mask of FIG. 1 are assembled;

7A to 7C are schematic cross-sectional views illustrating a process in which the mask assembly of FIG. 2 is suspended on a panel to correct a dope phenomenon.

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

1 is an exploded perspective view illustrating an assembly of a mask assembly newly implemented according to an embodiment of the present invention, FIG. 2 is a perspective view showing a state in which the mask assembly of FIG. 1 is assembled, and FIG. 4A to 4D are process diagrams showing a semipress process of a shadow mask according to the present invention, and FIGS. 5 to 6 are frames and masks of another embodiment according to the present invention. 7A to 7C are views for explaining how to correct the amount of dominance when the mask assembly shown in FIG. 2 is suspended inside the panel and dope by an electron beam.

The mask assembly newly implemented by the present invention includes a shadow mask 1 having a flat central portion and a frame 7 for fixing the shadow mask 1 as shown in FIGS. 1 and 2.

The shadow mask 1 has a color-selective function of landing three lines of electron beams emitted from the electron gun to the corresponding phosphors of red, green, and blue colors, and is formed in a rectangular shape, and a plurality of electron beams through which the electron beams pass in the center part. The perforated part 3 through which the through-hole is densely located is located, and the perforated part 3 is fixed to the frame around the perforated part 3.

The through hole drilled in the hole (3) can be either slot type or round shape, but in this embodiment, a suitable slot type is drilled in the cathode ray tube for the priority of luminance, and the method of drilling is performed by photolithography as in the prior art. It is carried out by the application of corrosion, detailed description is omitted.

In addition, the perforations 3 are formed in a flat surface in which both vertical and horizontal curvatures V _R 1 (H _R 1) reach infinity.

The non-perforated part 5 is a periphery part 5a formed in the periphery of the perforated part 3 again, and a side part in which both short sides of the periphery part 5a are bent in the opposite direction of the panel (see FIG. 7). 5b).

In the present embodiment, the side portion 5b is formed at both end portions of the non-perforated portion 5, but may also be formed at both long edge portions as shown in FIG.

As described above, forming the perforations 3 of the shadow mask 1 in a flat manner and forming the side portions 5b may be performed by using a punch (see FIG. 4), a pad (see FIG. 4), and a die (see FIG. 4). It is carried out using a press type (see Fig. 4) included, this operation is called a semi-press step in the present invention.

The semi-press process will be described in more detail as shown in Figs. 4A to 4D, and the press type P has a shader in addition to the punch 9, the pad 11, and the die 13 described above. 15 and the back plate 17, wherein the punch 9 and the shader 15 are formed in a plane in contact with the shadow mask 1 in a plane.

First, when the shadow mask 1 is seated on the die 13 positioned between the punch 9 and the shadower 15, the pad 11 is lowered to fix the non-perforated part 5 and the punch 9 is again It descends under load and forms the hole 3 in a plane.

Then, the punch 9 and the shader 15 are lowered to the back plate 17 in the above state, and the ends of the non-perforated parts 5 are formed into vertically bent side parts 5b, and then again after a while. When it rises and returns to an initial state, the semipress process of the shadow mask 1 is completed.

As described above, the hole 3 of the shadow mask 1 has a side portion 5b that is flatly formed and bent toward the panel, and unlike the conventional shadow mask, high pressure is required to give curvature. Since it does not extend in all directions, the setting position of the through hole does not change, and it does not require annealing treatment to correct the elongation of the material.

The shadow mask 1 is formed of Invar steel having a fine thickness of 0.3 mm or less and low thermal expansion rate.

Meanwhile, the frame 7 is provided to fix the shadow mask 1 to be positioned on the inner side of the panel. In the present embodiment, the frame 7 is formed of Inba steel having the same material as that of the shadow mask 1, but is made of nickel (Ni). ) And an alloy metal of iron (Fe) can also be used.

The frame 7 is also integrally formed with two short sides 7b and a long side 7a facing each other around a hole through which an electron beam directed to the hole 3 of the shadow mask 1 can pass. The surface 7c facing the panel of the short side portion 7b and the long side portion 7a is in close contact or fixed to the peripheral portion 5a of the shadow mask 1, respectively.

In the present embodiment, both of the short side portion 7b and the long side portion 7c facing the panel are formed in a plane in which the vertical and horizontal curvatures V _R 2 (H _R 2) reach infinity. On the surface 19c facing the panel of the long side portion 19a such as the frame 19 shown in Fig. 5, only the vertical curvature V _R 3 is formed at infinity and the horizontal curvature H _R 3 is formed as a curved surface having a predetermined value. You can.

Therefore, according to the present embodiment, the frame 7 shown in FIG. 1 has the shadow mask 1 described above on the surface facing the panel, the side portions 5b formed at both short sides, and the side portions at the long sides as well as both short sides shown in FIG. All of the shadow masks 21 formed with the shadow mask 25b are mounted and fixed to form the mask assembly MA1 shown in FIG. 2, whereby the perforations 3 and 23 of the shadow mask 1 and 19 are formed. Is the same curvature V _R 2 (H _R 2), i.e., flat, as the surface 7c facing the panel of the frame 7.

In other words, when the curvatures V _R 2 and H _R 2 of the surface 7c facing the panel of the long side portion 7a and the short side portion 7b are both infinity, the perforated portion formed flat in the press form P. The curvature V _R 1 (H _R 1) of (3) (23) is to remain unchanged, and the horizontal curvature (H _R 3) of the surface 19c facing the panel of the long side portion 19a is predetermined. In the case of the frame 19 having the horizontal curvature (H _R 4) of the shadow mask 1 as shown in Figure 6 also has the same value.

At this time, the shadow mask (1) (21) and the frame (7) (19) is fixed to each other by welding, the position of the side of the shadow mask (1) (21) of the above-mentioned shadow mask (1) 21 to be welded (25b) In the case of the shadow mask (1), which has an inner side and an outer side surface of the frames (7, 19), and the side portions are not formed at both long sides, the bottom and the frame (7) of the periphery (5a) located at both long sides. It is set as the surface 7c toward the panel of ().

In addition, when the surface 19c facing the panel of the frame 19 has a constant curvature (H _R 3), it is preferable that the shadow mask 1 having the side portions 5b formed only on both of the short sides mentioned above is bonded and welded. The point is also the same as described above, but the surface 19c facing the panel of the long side portions 19a facing each other of the frame 19 has a curvature H _R 3, which is the same as the mask assembly MA2 shown in FIG. 6. One shadow mask 1 also has the same curvature H _R 3 as the surface 19c facing the panel of the long side portion 19a of the frame 19 as described above.

The operation of the mask assembly MA1 made as described above is as shown in Figs. 7A to 7C.

In detail, when the electron beam emitted from the electron gun (not shown) is directed to the fluorescent surface for landing on the corresponding phosphor (not shown), most of the electron beams do not pass through the through hole drilled in the hole 3 and the shadow is not provided. It hits the mask 1.

As a result, as time passes, the shadow mask 1 is formed of Invar steel, which is resistant to thermal expansion, but causes thermal expansion to cause a dominant phenomenon in which the convex toward the panel 27 occurs. This is delivered and spread everywhere.

At this time, the thermal expansion of the frame 7 is greater than that of the shadow mask 1, although the thermal expansion of the frame 7 is made of the same Invar steel as the shadow mask 1, and the side portion 5b of the shadow mask 1 is the frame 7 The tension of the shadow mask 1 is applied to the perforations 3 of the shadow mask 1 because it is firmly fixed to the side surface of the mask, and the pulling force is canceled and the electron beam is normally landed on the corresponding phosphor. .

Therefore, although the shadow mask 1 does not have a tensile force unlike a conventional tension mask, it acts similar to a conventional tension mask having a tensile force.

This action is the same in the mask assembly MA2 having the predetermined horizontal curvature described above.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it belongs to the scope of the invention.

As described above, the mask assembly is formed in a semi-press process so that the pores of the shadow mask are not flat but are not stretched, thereby preventing spring back or uneven curvature and eliminating the need for a separate annealing treatment.

The shadow mask is fixed by giving a curvature to the frame, and at the same time, since the perforations are made of the same curvature, the ease of operation is greatly improved.

In addition, since the dominant amount of the shadow mask is corrected by the amount of thermal expansion of the frame, a separate process of applying a tensile force disappears even though the perforations are flat or cylindrical.

Claims (7)

A number of electron beam through holes are formed in the center of the flat plate, and both short ends are bent in the opposite direction of the panel. A mask; There is a flat form. When the mask is attached includes a frame formed with a constant curvature on the long side to form a curvature to the horizontal side, There is a reminder. The mask assembly of the cathode ray tube, characterized in that the part facing the frame is completely in contact with the vertical curvature is infinite and only the horizontal curvature is formed. The method of claim 1, wherein. The mask assembly of a cathode ray tube, characterized in that both short sides and both long sides are bent in the opposite direction of the panel. The mask assembly of claim 1, wherein the frame has an infinite surface facing the panel of the two long sides, and the horizontal portion forms a curvature. The method of claim 1, wherein. Mask assembly of a cathode ray tube, characterized in that the mask is formed of Invar steel. The mask assembly of claim 1, wherein the frame is made of an Inba steel or a nickel-iron alloy metal. The method of claim 1, wherein. Mask and frame assembly of the cathode ray tube, characterized in that the bent end side of the mask and the outer side of the corresponding frame is welded. Preparing a mask frame having a long side having a curvature and a short side having an infinite curvature; Making an electron beam through hole in the planar member; Are made in the second step above. Contacting the mask with the frame such that a shadow mask is bent according to the curvature of the frame; Mask assembly of a cathode ray tube, the third step comprising welding and fixing the frame at the bent portion of the mask.

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