KR100449754B1 - Internal electrode fabrication method of electron gun for cathode ray tube and internal electrode fabricated thereof - Google Patents

Abstract

PURPOSE: A method and an internal electrode are provided to reduce manufacturing procedures and material consumption by including a blanking step of cutting strip type materials into squares with curved corners. CONSTITUTION: A method comprises a blanking step of cutting strip type materials into squares with curved corners; a drawing step of forming each of the cut materials into a cup(43) having a closed portion(43b), an open portion(43a), and an outer peripheral surface; a pre-piercing step of forming through holes(46) at positions corresponding to centers of beam passing holes(48) to be formed at the closed portion of the cup; an embossing step of recessing part of the closed portion of the cup corresponding to the positions where the beam passing holes are to be formed, into cylindrical shapes toward the open portion of the cup; and a piercing step of forming beam passing holes by removing bottoms of the recesses formed by the embossing step.

Description

Internal electrode fabrication method of electron gun for cathode ray tube and internal electrode fabricated etc.

The present invention relates to a method for manufacturing an internal electrode of an electron gun for cathode ray tubes and an internal electrode thereby, and more particularly, to an internal electrode manufacturing method of an electron gun for cathode ray tubes that can shorten the process and reduce the consumption of a strip of material, and thereby an internal electrode. It relates to an electrode.

Typically, the cathode ray tube includes a panel in which a fluorescent surface is formed inside, and a funnel in which the panel is provided on one surface, and an electron gun is installed in a neck of the funnel. The electron gun generates electron beams corresponding to red, green, and blue according to an electric signal and is scanned on the fluorescent surface of the panel to display a predetermined image.

1 shows a schematic cross sectional view of an electrode with an indication of the voltage applied to each electrode in a conventional electron gun.

Referring to the drawings, the electron gun comprises a cathode (2), a control electrode (3) and a screen electrode (4) forming a three-pole portion, and first, second, three, and four focus electrodes (5) and (6) forming a main lens system. 7) (8) and the final acceleration electrode (9) provided to face the fourth focus electrode (8). Here, three cathodes 2 are arranged inline, and each of the electrodes arranged from the cathode 2 is formed with three electron beam through holes in-line. On the mutually opposing surfaces of the third and fourth focus electrodes 7 and 8, means 7a, 7h, 8a, and 8h for forming quadrupole lenses are provided.

A predetermined constant voltage VS is applied to the screen electrode 4 and the second focus electrode 6, and a focus voltage higher than the constant voltage VS is applied to the first and third focus electrodes 5 and 7. VF) is applied, a dynamic focus voltage VD having the focus voltage as a base voltage is applied to the fourth focus electrode 8, and an enwood voltage VA higher than the voltages is applied to the final acceleration electrode 9. ) Is applied.

In the electron gun for the conventional color cathode ray tube configured as described above, the fourth focus electrode indicated by reference numeral 8 and the final acceleration electrode indicated by reference numeral 9 are composed of an inner electrode and an outer electrode. That is, as can be seen in the figure, the fourth focus electrode 8 includes a left outer electrode 8a coupled to the third focus electrode 7 and a right outer electrode coupled to the left outer electrode 8a. 8b and an inner electrode 8c provided inside the right outer electrode 8b. The final acceleration electrode 9 also has an external electrode 9a and an internal electrode 9b provided inside the external electrode 9a.

As described above, an electrode having an external electrode and an internal electrode is a process of continuously blanking, drawing, and trimming a material provided in a strip form using a progressive mold. Is done through. In particular, the inner electrode requires careful process control in manufacturing, since the landing position of the electron beam may vary depending on the subtle difference in the position where the inner electrode 8c or 9b is installed in the outer electrodes 8b and 9a. . That is, even though three through holes through which the electron beam passes, are precisely formed in the inner electrode, the landing of the beam varies according to the relative installation positions of the inner electrode 8c or 9b and the outer electrodes 8b and 9a.

FIG. 2 is a schematic exploded perspective view of one electrode of an electron gun having an inner electrode and an outer electrode as described above.

Referring to the drawings, the inner electrode 22 is inserted into and installed in the space formed inside the outer electrode 21, wherein the outer circumferential surface 24 of the inner electrode 22 is the inner circumferential surface 25 of the outer electrode 21. Keep in contact. The shape and size of the outer circumferential surface 24 of the inner electrode 22 should match the shape and size of the inner circumferential surface 25 of the outer electrode 21. If this does not coincide, the position of the beam through hole 23 is changed, so that the beam landing is not made correctly.

3A to 3I show a schematic perspective view of a method of manufacturing an internal electrode according to the prior art.

3A and 3B, first, the material of the internal electrode is provided in the form of a strip 31, which is subjected to a blanking (FIG. 3B) which is cut into the form of a circle 32. . The size of the strip 31 is provided taking into account the size of the circle after the completion of blanking, and the width of the strip 31 should be larger than the diameter of the blanked circle 32.

Referring to FIG. 3C, this shows drawing a blank material in the form of a cup 33 in the form of a cup 33. Drawing is performed with a mold of the desired type using the ductility of the material. In actual work, the draw processing is divided into primary and secondary, and performed with different molds, thereby making a more precise drawing operation. After the drawing process is completed, the material is formed in the shape of a cup having an open portion 33a and a closed portion 33b as a whole, and a playing portion 33 is formed at the open end of the cup.

3D shows a state in which the trimming process is completed. Trimming is a process of removing the playing part 34 of the material having the shape of the cup 33 in FIG. 3C, which is performed using a punch. The trimming process may generate burrs on the outer circumferential surface of the internal electrode, and thus high working precision is required.

3E shows a state in which pre piercing processing is completed. The preliminary drilling operation corresponds to a preliminary operation for forming beam passing holes. Preliminary drilling is to penetrate the point corresponding to the center of the beam passing hole in the closing portion 33b of the cup 35 using a punch for punching. As shown in the figure, there are three through holes 36 formed by the preliminary perforations, which correspond to the center positions of the beam through holes of the inner electrode to be formed later.

3F shows a state in which embossing is completed. Embossing projects the closure 33b within a predetermined radius about the through hole 36 formed in the preliminary drilling step in the direction of the opening 33a. When the embossing is completed, as shown in the drawing, three recesses 37 are formed in the closed portion 33b of the cup 33, and the through hole 36 is formed at the bottom of the recessed portion 37. Will be. The wall formed on the side of the depression 37 becomes the side wall of the beam through hole in the final completed internal electrode. In actual work, embossing is carried out over three orders, whereby a depression 37 of the correct diameter and depth is formed.

3G shows a state in which piercing processing is completed. The punching process completely punches the bottom of the bottom surface of the depression 37 using a punch. That is, in the preliminary drilling shown in FIG. 3E, the through hole is formed at a point corresponding to the center of the depression 37, but in the drilling shown in FIG. 3G, the entire bottom surface of the recess 37 is penetrated. Therefore, the beam through hole 38 consisting of the through hole 36 'and the side wall is completed.

The internal electrode formed as above is completed through burring, which is the final machining operation. Burring is to process the outer peripheral surface 39 of the inner electrode to match the inner peripheral surface of the outer electrode using a mold. In actual work, the burring work is performed in three divisions, including reverse burring.

The above-described internal electrode manufacturing method of the prior art has the following problems.

First, the amount of material discarded is excessive compared to the amount of material finished with the product. As can be seen in FIG. 3A, since the material is blanked in the form of a circle 32 from the material provided in the form of a rectangular strip, all material left in the margin is discarded, thus increasing the overall material consumption. Done.

Second, unnecessary processes are added. The trimming process shown in FIG. 3D is a necessary process because the blank material is initially blanked in the form of a circle, and can be excluded if the playing part 34 does not occur by blanking the material in another form.

Third, the accuracy of the outer peripheral surface of the inner electrode is highly likely to be lowered. This decrease in accuracy results from the formation of the playing section 34 and the trimming process. That is, when the playing part 34 is not properly removed in the trimming process, burrs are generated at the cut surface, and such burrs are not likely to be properly removed by the subsequent burring removal process. .

The present invention has been made to solve the above problems, an object of the present invention is to provide a method for manufacturing an internal electrode of the electron gun that can reduce the material consumption.

Another object of the present invention is to provide a method for manufacturing an internal electrode of an electron gun, in which the manufacturing process can be simplified.

Another object of the present invention is to provide a method for manufacturing an internal electrode of an electron gun, in which the precision of a product can be improved.

Another object of the present invention is to provide an internal electrode of an electron gun for a cathode ray tube manufactured by an improved method.

1 shows a schematic cross-sectional view of an electrode with an indication of the voltage applied to each electrode in a conventional electron gun.

2 is a schematic exploded perspective view of an outer electrode and an inner electrode.

3A to 3G are explanatory diagrams showing a manufacturing process of an internal electrode according to the prior art.

4A to 4F are explanatory diagrams showing a manufacturing process of an internal electrode according to the present invention.

<Brief Description of Major Codes in Drawings>

2. cathode 3. control electrode

4. Screen Electrodes 5.6.7.8. Focus electrode

9. Final Acceleration Electrode 21. External Electrode

22. Internal electrode 23. Beam through hole

24. Outer surface 25. Inner surface

33.43. Cup 34. Performance

36.46.Through Hole 37.47. Depression

38.48. Beam through hole

In order to achieve the above object, according to the present invention, a blanking step of cutting the material continuously provided in the form of a strip in the form of a square formed with a curved corner portion, the cut material is closed, opening and outer peripheral surface Draw step of forming in the form of a cup having a preliminary drilling step to form a through hole at a position corresponding to the center of the beam through hole to be formed in the closed portion of the cup, the cup corresponding to the formation position of the beam through hole Manufacturing an internal electrode of an electron gun for a cathode ray tube including an embossing step of cylindrically recessing a part of a closed part of the cup toward the opening part of the cup, and a drilling step of forming the beam through hole by removing a bottom bottom of the depression formed by the embossing. A method is provided.

In addition, according to the present invention, in the inner electrode of the cathode ray tube electron gun having a closed portion formed with a cylindrical beam through hole, an open portion formed in the opposite direction of the closed portion, and an outer circumferential surface extending between the closed portion and the open portion, The inner electrode is provided with an inner electrode of an electron gun for a cathode ray tube, characterized in that formed from a rectangular material having a corner portion formed in a curve.

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

4A to 4G illustrate an internal electrode manufacturing method of an electron gun for a cathode ray tube according to the present invention.

4a and 4b show blanking of the material of the internal electrodes which are provided continuously in the form of a strip. As can be seen in the figure, the material 41 in strip form is blanked in such a way that the playing part does not occur when a draw process, which is a subsequent process, is performed. This is, for example, cutting four corners of a rectangle into a curved rectangular shape 42, which is performed by blanking using a mold. By having a rectangular shape 42 having such a curved edge, the amount of material that is discarded without being used as an internal electrode can be significantly reduced.

4C shows a draw process of the material 42 of a predetermined shape blanked. Through the drawing process using a mold, the material is in the form of a cup 43. The cup 43 has an opening part 43a and a closing part 43b, and has an outer peripheral surface 44c. In actual work, it is preferable that the draw processing is performed in the primary and secondary manner so that the shape of the cup 43 can be precisely made. Unlike the manufacturing method of the prior art described above, the playing part 34 (FIG. 3C) is not formed in the open end of the cup 43 in the drawing process of this invention. Thus a separate trimming process is excluded.

4D shows that pre piercing has been performed to the closure 43b of the cup 43. The preliminary drilling is to form the through hole 46 in advance by using a punch or the like at a position corresponding to the center of the portion where the beam passing hole of the internal electrode is to be formed. The through holes 46 are formed in three places in the closing portion 43b of the cup 43.

4E shows that embossing has been performed. The recessed part 47 is formed in the closed part 43a of the cup 43 by embossing. The depression 47 is formed in a cylindrical shape by recessing a part of the closing portion 43b of the cup 43 corresponding to the beam passing hole toward the opening 43a. The depression 47 corresponds to the side wall of the beam through hole of the final inner electrode. Therefore, the depression 47 is formed in a circular shape having a predetermined diameter. The through hole 46 formed by the preliminary drilling is formed at the bottom of the bottom of the recess 47. Embossing may be carried out several times to improve machining precision.

In FIG. 4F, the bottom of the bottom of the depression 47 of the cup 43 is drilled. This process forms a complete through 46 'by removing the bottom of the depression 47 using a punch, which forms the beam through hole 48 at the finished internal electrode.

Afterwards, the inner electrode is subjected to a burring process so that the inner electrode can be accurately installed inside the outer electrode, which can be divided into several processes including reverse burring as in the prior art. Through the burring process, the outer circumferential surface 44c of the inner electrode coincides with the outer circumferential surface of the outer electrode, whereby the electron beam passing through the beam passing hole can accurately land at a predetermined position of the fluorescent surface.

In the method for manufacturing an internal electrode of the electron gun according to the present invention, the required amount of material can be drastically reduced by changing the shape formed by the initial blanking into a rectangular shape having a curved edge portion. For example, about 45% of the material can be saved than in the prior art when blanking is performed in the form of a circle. In addition, by excluding the process such as trimming, the process can be simplified and manufacturing cost can be reduced, and the generation of burrs due to trimming is suppressed, thereby improving machining precision.

Although the present invention has been described with reference to one embodiment shown in the accompanying drawings, it is only an example and those skilled in the art can understand that various modifications and equivalent other embodiments are possible therefrom. There will be. Therefore, the true technical protection scope of the present invention should be defined only by the appended claims.

Claims (2)

A blanking step of cutting the material, which is continuously provided in the form of a strip, into the shape of a rectangle having curved edges, A drawing step of forming the cut material in the form of a cup having a closure, an opening, and an outer circumferential surface; Preliminary drilling step of forming a through hole at a position corresponding to the center of the beam through hole to be formed in the closed portion of the cup, An embossing step of cylindrically recessing a portion of the closed portion of the cup corresponding to the position where the beam through hole is formed, toward the opening of the cup; And a drilling step of forming the beam through hole by removing the bottom of the bottom surface of the depression formed by the embossing. An inner electrode of an electron gun for a cathode ray tube having a closed portion having a cylindrical beam passing hole, an opening formed in an opposite direction of the closed portion, and an outer circumferential surface extending between the closed portion and the open portion, A blanking step of cutting the material, which is continuously provided in the form of a strip, into the shape of a rectangle having curved edges, A drawing step of forming the cut material in the form of a cup having a closure, an opening, and an outer circumferential surface; Preliminary drilling step of forming a through hole at a position corresponding to the center of the beam through hole to be formed in the closed portion of the cup, An embossing step of cylindrically recessing a portion of the closed portion of the cup corresponding to the position where the beam through hole is formed, toward the opening of the cup; The inner electrode of the cathode ray tube electron gun, characterized in that formed by a method comprising a perforating step of forming the beam through hole by removing the bottom bottom of the depression formed by the embossing.

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