KR100342042B1 - Serial cathode structure - Google Patents

Abstract

PURPOSE: A serial cathode structure is provided to reduce a fabricating cost by improving a support structure of a filament for supporting a porous pellet. CONSTITUTION: A serial cathode structure has a porous pellet as an electron emission source. The porous pellet is formed by performing a pressing process, a molding process, and sintering process for powder of high fusion point metal such as tungsten and molybdenum. The porous pellet has various sections such as polygon, a circular shape, and a hexahedron. A filament portion is divided into a first and a second filaments(510,520). The first filament(510) and the second filament(520) have a first and a second bodies(511,521) and a first and a second branch portions(512,522) branched from the first and the second bodies(511,521), respectively.

Description

Direct Cathode Structure

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a series of negative electrode structures for cathode ray tubes, and more particularly, to a series of dispensing cathode structures of electron guns for color cathode ray tubes.

The cathode emits hot electrons through thermal energy, and is classified into a direct heat type by a direct heating method and a heat dissipation type by an indirect heating method according to the heating method.

The direct heat cathode has a structure in which the filament and the hot electron emission source are in contact, and the heat dissipation negative electrode has a structure in which the filament and the hot electron emission source are separated.

In general, a heat dissipating cathode is applied to an electron gun which requires a large amount of hot electrons, and is divided into, for example, an oxide cathode and a dispenser cathode, and includes a sleeve in which a filament is embedded and a base metal or a storage tank fixed to the sleeve. The base metal mainly has an oxide cathode and the reservoir has a dispenser cathode.

On the other hand, the direct type cathode is generally provided with a base metal or a storage medium that is directly fixed to the filament. In this structure, the base metal is mainly used for the electron gun of the small cathode ray tube for the viewfinder, and an oxide cathode is coated on the surface thereof. In addition, the storage medium may be applied to a large or industrial cathode ray tube requiring a large current, for example, a porous pellet impregnated with a negative electrode material as a dispenser type hot electron emission source.

Compared to the heat dissipation type cathode, the direct heating type cathode having a faster firing time of a cathode ray tube is usually bonded by direct resistance welding or special bonding in contacting a hot electron emission source, that is, a porous pellet and a filament that serves to heat it to a constant temperature. Braze using material.

In the conventional direct type negative electrode structure, the form in which the porous pellets are directly fixed to the filaments has been filed by the present applicant, in particular, in the Republic of Korea Application No. 91-9461, the structure of which is impregnated with the negative electrode material as shown in FIG. The filaments 102, 102 'are in direct contact with both sides of the porous pellet 101. In the conventional direct type negative electrode structure having such a structure, the filament 102 is directly welded to the side of the pellet 101 as shown in FIG. 2 according to the contact type of the filament, or as shown in FIG. As described above, the filament 102 'has a structure that is fixed in the form of penetrating the body of the porous pellet 101.

In addition, as another example of a form in which the porous pellet is directly fixed to the filament in the conventional direct type negative electrode structure, in the structure of FIG. 4, which is also filed by the applicant of the Korean patent applications 93-17567 and 94-12162 As described above, the filament 102 is in direct contact with at least three outer surfaces of the porous pellet 101 in which the negative electrode material is impregnated.

Thus, the conventional direct type negative electrode structure in which the filament is in direct contact with at least three places on the outer surface of the pellet also has the filament at three or more places on the side of the pellet 101 as shown in FIG. 5 according to the contact type of the filament. 102 is directly welded, or as shown in FIG. 6, the filament 102 has a structure that is fixed in the form of penetrating through the body of the porous pellet 101.

The above-described prior art direct-heat cathode structure has a form in which the porous pellet is directly heated by the filament in contact with the body and also generates heat directly by the current from the filament, so that the release of hot electrons after the application of current is started. Although it has the advantage of being very short and particularly capable of emitting high-density hot electrons, a cathode structure having a structure substantially as described above has a disadvantage in that welding of pellets and filaments is difficult. It is not easy to maintain high quality in practice and also has disadvantages in terms of productivity.

In view of the disadvantages of the conventional direct type negative electrode structure as described above, and improved, it is also a porous pellet (as shown in the structure of FIGS. 7 and 8 as filed in the Korean patent application 94-33109 by the applicant) A part of the filament 102 is in contact with the lower surface of the 101, and there is used an auxiliary member 201 that supports the contact portion of the filament 102 at the lower portion of the contact portion. Further, the first metal member 201 welded and fixed to the porous pellet 101, as in the structures of FIGS. 9 and 10, which have been filed by the applicant in Korean patent application 94-38990, and the first metal member The second metal member 202 is welded and laminated on the 201, and the filament 102 is interposed between the first metal member 201 and the second metal member 202. . According to the two improved structures of the above example, the welding reliability of the porous pellet and the filament may be improved, thereby enabling rapid hot electron emission, and at the same time, stabilizing the support structure of the filament for the porous pellet to improve quality and productivity.

On the other hand, Figure 11 is a modified embodiment of the series of negative electrode structure having the structure of Figures 9 and 10, the bonding material 301 is welded and fixed to the porous pellet 101, and the bonding material 301 and The filament 400 having the branch portion 402 branching from the body 401 of the same shape is laminated with welding. That is, in the structures of FIGS. 9 and 10, the filament 102 is formed integrally with the second metal member 202. In general, the bonding material serves to bond the porous pellets and filaments by hot pressing a powder made of molybdenum (Mo) or rudenium (Ru) between the porous pellets and the filaments. The integral filament is formed of a filament-shaped pattern by etching or stamping on a metal plate mainly composed of tungsten (W) or molybdenum (Mo), and then the pattern is formed. By cutting, the filament is mass produced.

As such, when the filament pattern is formed on the metal plate, the number of filament patterns per unit area of the metal tube is extremely limited due to the characteristics of the filament. Therefore, since the amount of waste is much greater than that of producing filaments from expensive metal plates such as tungsten or molybdenum, there is a problem that it acts as a major cause of cost increase in manufacturing the anode structure.

Therefore, the present invention was created in view of the above-described disadvantages of the conventional direct type negative electrode structure to improve it, and an object of the present invention is to improve the support structure of the filament for the porous pellets and to reduce the cost thereof. It is to provide a thermal cathode structure.

In addition, the present invention is to provide a series of negative electrode structure having a high current density and can significantly shorten the image outgoing time of the color cathode ray tube and at the same time reduce the cost.

In order to achieve the above object, the series cathode structure for cathode ray tube of the present invention,

In a linear negative electrode structure comprising a porous pellet impregnated with a negative electrode material, a bonding member laminated and fixed to the porous pellet, and a filament laminated and fixed to the bonding member,

Wherein the filament is divided into a first filament and a second filament, and the first filament and the second filament each have a body part laminated and fixed to the joining member, and a plurality of branches branched from the body part. It features.

In addition, in order to achieve the above object, the direct type negative electrode structure of the present invention,

A direct thermal type comprising a porous pellet impregnated with a negative electrode material, a bonding member laminated and fixed to the porous pellet, a filament laminated and fixed to the bonding member, a supporter supporting the filament, and an insulating block supporting the supporter. In the negative electrode structure,

Wherein the filament is divided into a first filament and a second filament, and the first filament and the second filament each have a body part laminated and fixed to the joining member, and a plurality of branches branched from the body part. It features.

In the linear cathode structure according to the present invention, in particular, the first filament and the second filament are preferably symmetrically divided, and each of the plurality of branch portions is preferably branched at a predetermined angle. It is preferable that four branch portions are arranged in a crisscross shape. The shape of the cross section corresponding to the body portion of the first filament and the body portion of the second filament is preferably the same as that of the cross section formed by the joining member, and the porous pellet is also the same as the cross section of the joining member. It is preferable to have a cross-sectional shape, and it is preferable that the shape of the cross section is formed so that it may have shapes, such as a circle, a polygon, a hexahedron. In addition, in the filament of the structure, it is possible to obtain several filament branch portions exposed from one body to the outside of the body of the pellet. Applicable for a color cathode ray tube.

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

FIG. 14 is a perspective view showing and extracting a main portion of a series negative electrode structure according to the present invention, and FIG. 15 is a perspective view showing and extracting a filament in the series negative electrode structure according to the present invention shown in FIG.

Referring to FIGS. 14 and 15, the direct type cathode structure according to the present invention is a porous pellet (501) as an electron emission source obtained by compression molding and sintering a powder of a high melting point metal such as tungsten and molybdenum. ). The porous pellet 501 can be modified in various forms such as a polygonal, circular disco, hexahedron, etc. in the shape of the cross section as in the conventional direct thermal cathode structure described above.

In addition, the welding member 502 is welded and fixed at a position vertically downward to coincide with the central axis of the porous pellet 501 in order to weld-fix the filaments 510 and 520 to the porous pellet 501. Like the porous pellet 501, the joining member may be modified in various shapes such as a polygon, a circular disk, a hexahedron, and the like, and preferably the same shape and the same as the porous pellet 501. It is better to have the outer dimensions.

In addition, the filament constituting the characteristic component of the linear cathode structure according to the present invention is divided into a first filament 510 and a second filament 520, and at the same time, the first filament 510 and the second filament 520 is a structure having a body portion 511, 521 laminated to the bonding member 502, and a plurality of branches 512, 522 branched from the body portion 511, 521, respectively. Consists of In particular, according to a feature of the present invention, the first filament 510 and the second filament 520 of the divided structure is divided symmetrically formed. At this time, if necessary, the branch portion of the filament welded to the bonding member 502 may be configured in such a way that several exposed to the outside of the body. The branched portions 512 and 522 branched from the body portions 511 and 521 of the first filament 510 and the second filament 520 are branched to form a predetermined angle, respectively. In this embodiment, the structure is branched into a crisscross shape and fixed in welding. Accordingly, four filament branches 512, 512, 522, 522 extend substantially downwards out of the body of the porous pellet 501 and the joining member 502. When the four filament branches are viewed as a single filament, the porous pellet 501 and the bonding member 502 welded thereto may have four legs. And, the filament 510, 520 may also serve as a heating element, but since the pellet 101 is directly heated, it serves as a leg for supporting the pellets. That is, since the filament is heated and its strength decreases, at least three or more filament branching portions 512 and 522 support the porous pellet 501 in a balanced manner, so that the supporting structure of the porous pellet 501 Stability. Therefore, the porous pellet 501 is not significantly affected by the impact from the outside, so that screen shaking or color change in the color cathode ray tube can be minimized.

On the other hand, in the direct type negative electrode structure according to the present invention, the split filaments are etched or stems on a metal plate mainly composed of tungsten (W) or molybdenum (Mo) as shown in FIG. After the filament-like pattern is formed by a method such as stamping, the filament can be mass-produced by cutting out the pattern. Although the method of manufacturing such filaments is the same as the method of manufacturing integrated filaments in the conventional direct type negative electrode structure described above, the split type filament of the direct type negative electrode structure according to the present invention has a pattern of filament on a metal plate. In the case of forming, by dividing the shape of the filament according to the characteristics of the present invention, the number of patterns of the filament that can be formed per unit area of the metal plate is much higher than in the prior art. Therefore, according to the present invention, since the amount of the filament generated from the expensive metal plate such as tungsten or molybdenum is much higher than that of the conventional method, the manufacturing cost can be greatly reduced.

On the one hand, the heating time is changed according to the specification, material, etc. of the porous pellet and filament, the difference in the initial electron emission time, such as the effective aspect and the ease of manufacture in the practical application must be considered. Therefore, the porous pellets and filaments, as well as the size and components of the bonding member is limited to the preferred state, which is limited to the same state as in the conventional direct type negative electrode structure. That is, for example, the porous pellet is an electron-emitting material having a porous gas metal tungsten (W) containing at least barium (Ba) as a main component, and the filament is mainly composed of tungsten (W), and tungsten (W) Rhenium (Re) may be added to the. In addition, the bonding member preferably includes molybdenum (Mo) and rudenium (Ru) as main components.

Therefore, the series negative electrode structure according to the present invention can attain productivity improvement by drastically reducing manufacturing costs while maintaining at least the same level of quality as in the prior art.

In the accompanying drawings, FIG. 17 shows a more specific example of the series cathode structure of the present invention that can be used in a monochromatic cathode ray tube. The pellet 101 is a hexahedron and is provided with filaments 102 on four sides, and the filaments 102 are welded and fixed to two supporters 301 installed upright on the fixing block 300. At this time, each supporter 301 is one filament 102 is welded and fixed so that the two filaments are connected in parallel, the current is applied through the two filaments, and is drawn out through the two filaments. This current applying structure can be applied to the above-described filament structure of the present invention. In this case, since the structure receives heat from a plurality of filaments, it is heated very quickly, and the hot electron emission is possible immediately after the current is applied.

FIG. 18 shows the present invention negative electrode structure that can be used for a color cathode ray tube, and has a structure in which three negative electrode structures of the unit structure of the present invention are provided in one insulating block. Have a supporter

In the case of forming the filament pattern on the metal plate by forming the filament in a divided form, the direct heat cathode structure according to the present invention described above has a filament which can be formed per unit area of the metal plate than when forming a pattern of a conventional single structure filament. The number of patterns is much increased.

Therefore, the direct-heat type negative electrode structure to which the split filament is applied according to the present invention has a much larger amount of filaments for producing filaments from tungsten or molybdenum and an expensive metal plate, thereby significantly reducing manufacturing costs. Has

1 is a perspective view showing the main portion of a conventional series negative electrode structure,

2 and 3 are cross-sectional views of types of the conventional series negative electrode structure shown in FIG.

4 is a perspective view showing the main portion of another conventional series of negative electrode structure,

5 and 6 are planar cross-sectional views of the type of another conventional series negative electrode structure shown in FIG.

7 is a perspective view showing the main portion of another conventional series of negative electrode structure showing

FIG. 8 is a perspective view showing an essential part of another embodiment of the conventional another series of negative electrode structure shown in FIG.

9 is a perspective view showing an extract of the main portion of another conventional series negative electrode structure,

FIG. 10 is a perspective view showing an essential part of another embodiment of another conventional series type negative electrode structure shown in FIG. 9;

11 is a perspective view showing the main portion of another conventional series of negative electrode structure showing

FIG. 12 is a perspective view showing an extract of a filament in the conventional series negative electrode structure shown in FIG.

FIG. 13 is a schematic plan view showing a pattern of a metal plate for manufacturing a filament of the conventional series negative electrode structure shown in FIG. 12;

Figure 14 is a perspective view showing the main portion of the heat extracting the negative electrode structure according to the present invention,

FIG. 15 is a perspective view showing and extracting a filament in a series negative electrode structure according to the present invention shown in FIG.

FIG. 16 is a schematic plan view showing a pattern of a metal plate for manufacturing a filament of a series negative electrode structure according to the present invention shown in FIG. 15;

FIG. 17 is a side view showing a state in which the series cathode structure according to the present invention is assembled for a monochromatic cathode ray tube, and

18 is a perspective view showing a state in which the series cathode structure according to the present invention is assembled for a color cathode ray tube.

* Explanation of symbols for main parts of drawings

101 ‥‥ Porous Pellets 102 ‥‥ Filament

201 ‥‥ First metal member 202 ‥‥ Second metal member

300 ‥‥ Fixed Block 400 ‥‥ Supporter

Claims (22)

In a linear negative electrode structure comprising a porous pellet impregnated with a negative electrode material, a bonding member laminated and fixed to the porous pellet, and a filament laminated and fixed to the bonding member, Wherein the filament is divided into a first filament and a second filament, and the first filament and the second filament each have a body part laminated and fixed to the joining member, and a plurality of branches branched from the body part. A series negative electrode structure, characterized in that. The method of claim 1, And the first filament and the second filament are symmetrically divided to each other. The method according to claim 1 or 2, And a plurality of branch portions of the first filament and the second filament are branched at a predetermined angle, respectively. The method according to claim 1 or 2, And a plurality of branched portions of the first filament and the second filament are formed such that four branched portions are arranged in a crisscross shape. The method according to claim 1 or 2, The cross-sectional shape of the cross section formed by the body portion of the first filament and the body portion of the second filament corresponding to the shape of the cross section formed by the joining member, characterized in that the linear structure. The method of claim 1, The porous pellet is a direct-type negative electrode structure, characterized in that it has the same cross-sectional shape as the carbon surface shape of the bonding member. The method of claim 1, The cross-sectional cathode structure of the porous pellet, the bonding member and the body portion of the first filament and the body portion of the second filament correspondingly formed in a circular shape. The method of claim 1, Wherein the porous pellet and the bonding member and the body portion of the first filament and the body portion of the second filament correspondingly formed while the shape of the linear cathode structure, characterized in that formed in a polygon. The method of claim 1, The cross-sectional shape of the porous pellet and the joining member and the body portion of the first filament and the body portion of the second filament corresponding to the cross-sectional shape is formed of a hexahedron. The method of claim 1, The cross-sectional cathode structure of the porous pellet, the bonding member and the body portion of the first filament and the body portion of the second filament correspondingly formed are different from each other. A series negative electrode comprising a porous pellet impregnated with a negative electrode material, a bonding member laminated and fixed to the porous pellet, a filament laminated and fixed to the bonding member, a supporter supporting the filament, and an insulating block supporting the supporter. In the structure, Wherein the filament is divided into a first filament and a second filament, and the first filament and the second filament each have a body part laminated and fixed to the joining member, and a plurality of branches branched from the body part. A series negative electrode structure, characterized in that. The method of claim 11, And the first filament and the second filament are symmetrically divided to each other. The method according to claim 11 or 12, wherein And a plurality of branch portions of the first filament and the second filament are branched at a predetermined angle, respectively. The method according to claim 11 or 12, wherein And a plurality of branched portions of the first filament and the second filament are formed such that four branched portions are arranged in a crisscross shape. The method according to claim 11 or 12, wherein The cross-sectional shape of the cross section formed by the body portion of the first filament and the body portion of the second filament corresponding to the shape of the cross section formed by the joining member, characterized in that the linear structure. The method of claim 11, The porous pellet is a direct-type negative electrode structure, characterized in that it has the same cross-sectional shape as the cross-sectional shape of the bonding member. The method of claim 11, The cross-sectional cathode structure of the porous pellet, the bonding member and the body portion of the first filament and the body portion of the second filament correspondingly formed in a circular shape. The method of claim 11, The tandem cathode structure, characterized in that the shape of the ball surface formed by the porous pellet, the bonding member and the body portion of the first filament and the body portion of the second filament correspond to a polygon. The method of claim 11, The cross-sectional shape of the porous pellet and the joining member and the body portion of the first filament and the body portion of the second filament corresponding to the cross-sectional shape is formed of a hexahedron. The method of claim 11, The cross-sectional cathode structure of the porous pellet, the bonding member and the body portion of the first filament and the body portion of the second filament correspondingly formed are different from each other. The method of claim 11, A plurality of pairs of supporters are provided on the insulating block at predetermined intervals, and a plurality of porous pellets are provided to correspond to the supporters. The method of claim 21, The supporter is three pairs, the porous cathode structure, characterized in that three porous pellets.