JP3152477B2 - Color cathode ray tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cathode ray tube display device such as a color cathode ray tube (hereinafter referred to as a color cathode ray tube) provided with an in-line electron gun, and more particularly to a cathode for an in-line electron gun having excellent electrical insulation characteristics. The present invention relates to a color cathode ray tube having a support structure.

[0002]

2. Description of the Related Art A color cathode ray tube has a structure in which an electron gun for emitting an electron beam, a shadow mask as a color selection electrode, and a phosphor layer constituting a display surface are held in a vacuum vessel. As this type of color cathode ray tube, a so-called in-line type electron gun, in which at least three electron guns are arranged in a straight line, is widely used.

In an electron gun used in a color cathode ray tube of a system in which a plurality of electron guns are arranged in-line, a first grid electrode constituting each electron gun has a cup shape, and the first grid electrode in the cup shape has Then, a method of supporting and fixing the cathode structure using an insulating substrate is adopted. FIG.
1 is a cross-sectional view illustrating a schematic structure of a color cathode ray tube using an inline array electron gun, wherein 1 is a panel, 2 is a funnel, 3 is a neck, 4 is an inline electron gun, 5 is a shadow mask, and 6 is a phosphor. Layer 7 is a deflection yoke.

In FIG. 1, electron beams R, B, and G emitted from three electron guns constituting an in-line electron gun 4 are shown.
Are two-dimensionally deflected by the deflection yoke 7 and are formed on the inner surface of the panel 1 through the shadow mask 5.
Is scanned. The electron beams R, G, B are red, green,
The original image is reproduced on the fluorescent layer 6 after being modulated by the blue image signal.

FIG. 8 is a sectional view of a main part of an electron gun for explaining a cathode structure of the in-line electron gun, and is 10 (R, G, B).
Is a cathode structure, 20 (R, G, B) is a first grid, 30
Denotes a second grid, 31 to 33 denote electron gun constituent electrodes below the third grid, and H denotes a heater. The illustrated electron gun is an example of this type of three-electron gun, and it goes without saying that there are electron guns having various electrode configurations in addition to such a configuration.

In this type of color cathode ray tube, a conventional example of an electrode structure in which three cathodes are supported and fixed in a first grid by an insulating substrate is disclosed in JP-A-55-16133.
The one disclosed in Japanese Patent Publication No. 7-107 is known. Also,
Japanese Patent Application Laid-Open No. 50-120564 discloses that three cathode structures are independently supported and fixed on an insulating substrate, and a metal supporting member surrounding the insulating substrate has a flat shape in the inline arrangement direction of the electron gun. Is disclosed.

FIG. 9 is an explanatory view of the above-described conventional cathode support structure viewed from the first grid side along the line ZZ in FIG. 8, where 011 denotes an electron-emitting substance, 012 denotes a base metal, and 013.
Is a cathode sleeve, 014 is a cathode tab for suspending the cathode sleeve, 015 is a cylindrical metal body, 016 is a crystallized glass substrate, and 017 is a metal support member. In addition, the cathode structure part 018 includes the electron emission material 011, the base metal 012, the cathode sleeve 013, and the cathode tab 014 which suspends the cathode sleeve.
And the cylindrical metal body 015, the insulating substrate 016, and the metal support member 017 constitute the cathode support structure part 019.

In the above-described conventional cathode support structure having three cathode structures, the electron emitting material 011 is a thermionic emitting material, and the base metal 01 containing a reducing agent therein.
2 is applied. The base metal 012 is formed into a cylindrical metal body 015 by a cathode sleeve 013 and four cathode tabs 014.
Supported and fixed. The cylindrical metal body 015 is made of SiO
_The metal support member 01 is formed by an insulating substrate 016 made of crystallized glass mainly containing ₂ , B ₂ O ₃ , ZnO ₂ , MgO or the like.
7 is fixed.

The cathode assembly part 018 is provided with a cathode sleeve 013.
A heater (not shown) is provided in the inside, and the thermoelectron emitting material 011 and the base metal 012 are heated to appropriate temperatures to emit thermoelectrons. Cathode support structure part 019
Is held and fixed to the electron gun structure by a first grid (not shown) or the like. The shape of the cathode support structure portion 019 is, for example, as shown in Japanese Patent Application Laid-Open No. 50-120564, while the metal support member 017 has a flat shape in the inline arrangement direction of the electron gun, while the cylindrical metal member 015 is a hollow cylinder having a circular cross section.

[0010]

In the prior art as described above, a metal support member 017 having a flat cross section in the inline arrangement direction of an electron gun and a cylindrical metal body 015 having a circular cross section are combined to form a cathode. Since the support structure is formed, the distance between the two becomes narrow in the short axis direction of the metal support member 017. For this reason, there is a problem that the insulating characteristics are deteriorated, and the mass productivity of the insulating substrate 016 and the cathode support structure portion 019 is reduced.

In other words, the pitch dimension of the cathode structure shown in FIG. 9, that is, the dimension in the XX direction (the dimension d in the figure) mainly depends on the focus characteristic which determines the resolution of the color cathode ray tube, the three colors red, green and blue. Is determined by the convergence characteristic indicating the concentration of Generally, in order to improve the convergence characteristics, it is advantageous to reduce the above-mentioned d dimension. 44, no. 5 (1990), p
As shown in pages 550 to 557, in the system using an elliptical aperture in the main lens portion of the electron gun structure, it is necessary to reduce the d dimension in order to improve the focus characteristics.

Further, in order to reduce the power consumption of the entire TV set, the diameter of the portion of the color cathode ray tube where the electron gun assembly is disposed is reduced to reduce the deflection power (ie, the neck diameter is reduced). However, in this case as well, the d dimension is reduced. The dimension d determines the minor axis diameter (diameter in the X-X direction) of the metal support member 017 in FIG. 9, while the cylindrical metal body 015 is determined by the structure of the heater / cathode assembly, and is easily determined. It cannot be reduced.
As a result, the distance between the metal support member 017 and the cylindrical metal body 015 is reduced, and the following two problems occur.

1. The withstand voltage characteristics deteriorate. Usually, a cathode potential is applied to the cylindrical metal body 015, and a ground potential (first grid potential) is applied to the metal support member 017. If the distance between the two becomes narrow, the withstand voltage characteristics deteriorate. 2. It becomes difficult to manufacture the insulating substrate 016 and the cathode supporting structure 019. Tubular metal body 015 and metal support member 017
The insulating substrate 016 is disposed between them. However, if the width of the insulating substrate 016 at a portion sandwiched between the cylindrical metal body 015 and the metal supporting member 017 becomes narrow, it becomes difficult to manufacture the insulating substrate 016. As a result, mass productivity of the cathode support structure portion 019 is deteriorated.

An object of the present invention is to solve the above-mentioned problems of the prior art, to increase the withstand voltage between the tubular metal body 015 and the metal support member 017, and to facilitate the manufacture of the insulating substrate 016 and the cathode support structure part 019. It is an object of the present invention to provide a color cathode ray tube including a cathode support structure for an in-line electron gun having a structure which can be performed as follows.

[0015]

In order to achieve the above object, the present invention provides a cylindrical metal body having an outer periphery in contact with the insulating substrate and having a cross section perpendicular to an axis of an electron gun at least in a direction perpendicular to the axis of the insulating substrate. The contact portion has a flat shape in the inline arrangement direction of a plurality of electron guns from a conventional circular shape. Examples of the shape of the flat cross section include a shape surrounded by an arc and a straight line, an ellipse, and a rectangular shape.

That is, the present invention provides (1) an insulating substrate 16 for holding and fixing a plurality of cathode structures 18 arranged substantially in a straight line, and a metal supporting member 17 surrounding the outer periphery of the insulating substrate 16. A cathode support structure 19 for an electron gun in which a plurality of electron guns are arranged in-line while the plurality of cathode structures 18 are independently held by a cylindrical metal body 15 having an outer periphery in contact with the insulating substrate 16; The cross section of the metal body 15 perpendicular to the axis of the electron gun has a flat shape in the in-line arrangement direction X-X of the electron gun including the plurality of cathode assemblies 18.

(2) An insulating substrate 16 for holding and fixing a plurality of cathode structures 18 arranged substantially on a straight line, a metal support member 17 surrounding the outer periphery of the insulating substrate 16, In the cathode support structure 19 of an electron gun in which a plurality of electron guns are arranged in-line while the plurality of cathode structures 18 are independently held by the cylindrical metal body 15 contacting the
A cross section of the cylindrical metal body 15 perpendicular to the axis of the electron gun has two arc-shaped portions 1 existing in a direction perpendicular to the inline arrangement direction of the electron gun including the plurality of cathode assemblies 18.
5-1 and 15-2, and linear portions 15-3 and 15-4 formed in the in-line arrangement direction XX.

(3) An insulating substrate 16 for holding and fixing a plurality of cathode structures 18 arranged substantially on a straight line, a metal supporting member 17 surrounding the outer periphery of the insulating substrate 16, In the cathode support structure 19 of an electron gun in which a plurality of electron guns are arranged in-line while the plurality of cathode structures 18 are independently held by the cylindrical metal body 15 contacting the
The cross-sectional shape of the cylindrical metal body 15 perpendicular to the axis of the electron gun is substantially elliptical, and the elliptical arc portions 15-5 and 15-6 along the major axis of the ellipse are arranged in an inline arrangement of the electron gun. It is characterized by being in the direction XX.

(4) An insulating substrate 16 for holding and fixing a plurality of cathode structures 18 arranged substantially on a straight line, a metal support member 17 surrounding the outer periphery of the insulating substrate 16, In the cathode support structure 19 of an electron gun in which a plurality of electron guns are arranged in-line while the plurality of cathode structures 18 are independently held by the cylindrical metal body 15 contacting the
The cross section of the cylindrical metal body 15 perpendicular to the axis of the electron gun has a flat shape having a short axis in the in-line arrangement direction X-X of the electron gun including the plurality of cathode assemblies 18. It is characterized by having spaces 16-1 and 16-2 near the short axis of the cylindrical metal body 15 of the insulating substrate 16.

(5) An insulating substrate 16 for holding and fixing a plurality of cathode structures 18 arranged substantially on a straight line, a metal support member 17 surrounding the outer periphery of the insulating substrate 16, In the cathode support structure 19 of an electron gun in which a plurality of electron guns are arranged in-line while the plurality of cathode structures 18 are independently held by the cylindrical metal body 15 contacting the
A long side 1 in which a cross section of the cylindrical metal body 15 perpendicular to the axis of the electron gun is flat in the in-line arrangement direction XX.
It is characterized by being substantially rectangular with 5-7 and 15-8.

[0021]

The cross section of the cylindrical metal body 15 is made flat in the in-line arrangement direction XX of the electron gun, so that the distance between the cylindrical metal body 15 and the metal support member 17 is increased, and Withstand voltage characteristics between the metal support member 15 and the metal support member 17 are improved. Further, the insulating substrate 16 is usually formed by crystallizing glass into a predetermined shape as described in JP-A-57-170434 and JP-A-59-12546, and after pre-sintering. , The cylindrical metal body 15, the metal support member 17
At the same time, it is put in a predetermined jig and baked and bonded to each other to complete it.

However, according to the present invention, the cylindrical metal body 15
Is flattened in the in-line arrangement direction X-X of the electron gun, so that the interval between the cylindrical metal body 15 and the metal support member 17 is increased, and the mass productivity of crystallized glass shaping is improved. Mass production of structure production is improved. In addition, the joining point between the cathode tab 14 and the cylindrical metal body 15 can be substantially the same as the conventional circular case even when the cross section of the cylindrical metal body 15 is flat. The function can be maintained without the need to change the shape.

When the tubular metal body 15 is formed in a rectangular shape, or the means for supporting and fixing the cathode sleeve 23 to the tubular metal body 15 is replaced with the cathode tab, and the cathode wire 24 is used.
The same effect can be obtained with the above-mentioned configuration.

[0024]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a plan view of a cathode support structure according to a first embodiment of the present invention, as viewed from the first grid side, and FIG. 1B is a cross-sectional view taken along line YY in FIG. 11 is an electron emission material, 12 is a base metal, 13 is a cathode sleeve, 14 is a cathode tab, 15 is a cylindrical metal body, 1
5-1 and 15-2 are arc-shaped portions, 15-3 and 15-4 are linear portions, 16 is an insulating substrate, and 17 is a metal support member. In addition, the electron emission material 11, the base metal 12, the cathode sleeve 1
3. A cathode structure 18 is constituted by the cathode tab 14 which suspends the cathode sleeve, and a cathode support structure 19 is constituted by the cylindrical metal body 15, the insulating substrate 16 and the metal support member 17.

The electron-emitting substance is made of, for example, an oxide and is formed and fixed on the base metal 12.
Is supported by the cathode sleeve 13. The cathode tab 14 connects and supports and fixes the cathode sleeve 13 and the cylindrical metal body 15. The insulating substrate 16 is made of crystallized glass or the like, and the cylindrical substrate 15 and the metal supporting member 17 are supported and fixed by the insulating substrate 16.

FIG. 2 is an explanatory view of the cross-sectional shape of the cylindrical metal body in FIG. 1 and a typical example of dimensions thereof. This cylindrical metal body 15 is obtained by cutting both ends of a cylinder having a diameter of 4.2 mm. This is a shape obtained by molding so that the interval between the straight portions 15-3 and 15-4 is 3.6 mm. On the other hand, FIG.
The inner diameter of the metal support member 17 is 4.8 mm in a flat portion in the in-line arrangement direction XX of the electron gun. In the case of a conventional cylindrical metal body having a circular cross section, the distance between the cylindrical metal body 015 and the metal support member 017 is 0.3 mm, but in the present invention, it is 0.6 mm, which is twice the insulation distance. Can be obtained.

FIG. 3 shows a second embodiment of the cathode support structure according to the present invention. (A) A plan view seen from the first grid side.
FIG. 1B is a cross-sectional view taken along the line YY in FIG.
The same reference numerals correspond to the same parts, and 15-5 and 15-6 are oblong arc parts. In this embodiment, in this embodiment, the cylindrical metal body 15 has a substantially elliptical cross section perpendicular to the axis of the electron gun, and has an elliptical arc portion 15 along the major axis of the ellipse.
-5 and 15-6 are the in-line arrangement directions X- of the electron gun.
X.

In this embodiment, similarly to the first embodiment, the distance between the cylindrical metal body 015 and the metal support member 017 in the in-line arrangement direction XX of the electron gun is increased, and the insulation distance can be increased. . 4 (a) is a plan view illustrating a third embodiment of the cathode support structure according to the present invention as viewed from the first grid side, and FIG. 4 (b) is a cross-sectional view taken along line XX of FIG. The same reference numerals as those in FIG.
Reference numerals 6-1 and 16-2 denote spaces of the insulating substrate 16.

In the figure, the cross section of the cylindrical metal body 15 perpendicular to the axis of the electron gun is flat and has a short axis in the in-line arrangement direction XX of the electron gun including the plurality of cathode assemblies 18. It has a shape, and has spaces 16-1 and 16-2 near the short axis of the cylindrical metal body 15 of the insulating substrate 16. By providing the spaces 16-1 and 16-2 in the insulating substrate 16, the insulating characteristics between the cylindrical metal body 15 and the metal support member 17 can be further improved. In addition, the cylindrical metal body 15
May be the shape shown in FIG. 3 described above or FIG. 5 described later.

FIG. 5 illustrates a fourth embodiment of the cathode support structure according to the present invention. (A) A plan view seen from the first grid side,
FIG. 1B is a cross-sectional view taken along the line YY in FIG.
The same reference numerals correspond to the same parts, and 15-7 and 15-8 are the long sides of the tubular metal body 15. In the figure, the cross section of the metal support member 17 is substantially rectangular, and
A cross section perpendicular to the axis of the electron gun of No. 5 is substantially rectangular in shape having long sides 15-7 and 15-8 which are flattened in the in-line arrangement direction XX.

The metal supporting member 17 is not limited to such a rectangular shape but may be an elliptical shape or an elliptical shape as described in the above embodiments. Also in this embodiment, the insulation characteristics between the cylindrical metal body 15 and the metal support member 17 can be further improved. FIG. 6 shows a fifth embodiment of the cathode support structure according to the present invention.
(A) Plan view seen from the 1st grid side explaining an Example, (b) It is sectional drawing in alignment with YY of (a),
The same reference numerals as those in FIG. 1 correspond to the same parts, 21 is a tungsten pellet, 22 is a molybdenum cup, 23 is a cathode sleeve, and 24 is a cathode wire.

Referring to FIG.
Is a tungsten pellet impregnated with barium as an electron emitting substance, and this tungsten pellet 21 fixes the molybdenum cup 22. Further, the cathode sleeve 23 is supported and fixed by a cathode wire 24 made of tungsten which is stretched and welded between the cathode sleeve 23 and the molybdenum cup 22 to assemble a cathode assembly.

The cylindrical metal body 15 is supported and fixed to a metal support member 17 via an insulating substrate 16 made of crystallized glass.
The dimensions of the cross section of the cylindrical metal body 15 and the metal support member 17 perpendicular to the axial direction of the electron gun are the same as those in the first embodiment.
Also in this embodiment, the insulation characteristics between the cylindrical metal body 15 and the metal support member 17 can be further improved.

[0034]

As described above, according to the present invention,
By making the cross-sectional shape of the cylindrical metal body for supporting and fixing the cathode sleeve flat in the in-line arrangement direction of the electron gun, the interval between the cylindrical metal body and the metal supporting member becomes large, and the cylindrical metal body becomes large. In addition, it is easy to manufacture a metal support member for supporting and fixing the tubular metal body, and a cathode support structure including an insulating substrate interposed between the tubular metal body and the metal support member, and cost can be reduced.

Further, since the distance between the cylindrical metal body and the metal supporting member can be increased, the withstand voltage characteristics between the two can be significantly improved, and the assembling dimensions of the cathode structure and the cathode supporting structure can be reduced. Even if the body is flattened, it can be almost the same, so that the original characteristics of the cathode can be maintained, and there is no influence on the operation of the color cathode ray tube. A color cathode-ray tube having a structure can be provided.

[Brief description of the drawings]

FIG. 1A is a plan view illustrating a configuration of a first embodiment of a cathode support structure according to the present invention, as viewed from a first grid side;
(B) It is sectional drawing along the YY line of (a).

FIG. 2 is an explanatory diagram of a cross-sectional shape of a cylindrical metal body in FIG. 1 and a typical example of dimensions thereof.

3 (a) is a plan view illustrating a cathode support structure according to a second embodiment of the present invention, as viewed from the first grid side, and FIG.
It is sectional drawing along the YY line of (a).

4 (a) is a plan view of a cathode supporting structure according to a third embodiment of the present invention, as viewed from a first grid side, and FIG.
It is sectional drawing along the XX line of (a).

5 (a) is a plan view illustrating a cathode support structure according to a fourth embodiment of the present invention, as viewed from the first grid side, and FIG.
It is sectional drawing along the YY line of (a).

6 (a) is a plan view of a cathode support structure according to a fifth embodiment of the present invention, as viewed from the first grid side, and FIG.
It is sectional drawing along the YY line of (a).

FIG. 7 is a cross-sectional view illustrating a schematic structure of a color cathode ray tube using an inline array electron gun.

FIG. 8 is a sectional view of a main part of the electron gun for explaining a cathode structure of the in-line electron gun.

FIG. 9 is an explanatory view of a conventional cathode support structure viewed from the first grid side along the line ZZ in FIG. 8;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Electron emission material 12 Base metal 13 Cathode sleeve 14 Cathode tab 15 Cylindrical metal body 15-1, 15-2 Arc-shaped part 15-3, 15-4 Linear part 16 Insulating board 16-1 and 16-2 Space 17 Metal support member 18 Cathode structure 19 Cathode support structure

Claims (5)

(57) [Claims] 1. An insulating substrate for holding and fixing a plurality of cathode structures arranged substantially in a straight line, a metal supporting member surrounding an outer periphery of the insulating substrate, and a cylindrical metal contacting the outer periphery with the insulating substrate. A color cathode ray tube comprising an electron gun cathode support structure in which a plurality of electron guns are independently held by a body and a plurality of electron guns are arranged in-line, A color cathode ray tube comprising a cathode support structure for an inline electron gun, wherein a cross section perpendicular to an axis has a flat shape in the inline arrangement direction of the electron gun including the plurality of cathode structures. 2. An insulating substrate for holding and fixing a plurality of cathode structures arranged substantially on a straight line, a metal support member surrounding the outer periphery of the insulating substrate, and a cylindrical metal body contacting the outer periphery with the insulating substrate. A color cathode ray tube comprising an electron gun cathode support structure in which a plurality of electron guns are independently held by a plurality of electron guns and arranged in-line, whereby the axis of the electron gun of the cylindrical metal body Cross-section perpendicular to the in-line arrangement direction of the electron gun including the plurality of cathode structures, two arc-shaped portions present in a direction perpendicular to the in-line arrangement direction, and having a linear portion formed in the in-line arrangement direction, Color cathode ray tube comprising a cathode support structure for an in-line electron gun. 3. An insulating substrate for holding and fixing a plurality of cathode structures arranged substantially on a straight line, a metal supporting member surrounding an outer periphery of the insulating substrate, and a cylindrical metal body contacting the outer periphery with the insulating substrate. A color cathode ray tube comprising an electron gun cathode support structure in which a plurality of electron guns are independently held by a plurality of electron guns and arranged in-line, whereby the axis of the electron gun of the cylindrical metal body The cross section perpendicular to the ellipse is substantially elliptical, and the elliptical arc along the major axis of the ellipse,
A color cathode ray tube comprising a cathode support structure for an inline electron gun, wherein the cathode support structure is arranged in an inline arrangement direction of the electron gun. 4. An insulating substrate for holding and fixing a plurality of cathode structures arranged substantially on a straight line, a metal supporting member surrounding an outer periphery of the insulating substrate, and a cylindrical metal body contacting the outer periphery with the insulating substrate. And a color cathode ray tube comprising a cathode support structure of an electron gun in which a plurality of electron guns are independently held by a plurality of electron guns and arranged in an in-line manner. Has a flat shape having an end axis in the inline arrangement direction of the electron gun including the plurality of cathode structures, and the insulating substrate has a space near a short axis of the cylindrical metal body. A color cathode ray tube comprising a cathode support structure for an in-line electron gun. 5. An insulating substrate for holding and fixing a plurality of cathode structures arranged substantially on a straight line, a metal supporting member surrounding an outer periphery of the insulating substrate, and a cylindrical metal body contacting the outer periphery with the insulating substrate. A color cathode ray tube comprising an electron gun cathode support structure in which a plurality of electron guns are independently held by a plurality of electron guns and arranged in-line, whereby the axis of the electron gun of the cylindrical metal body A color cathode ray tube comprising a cathode support structure for an in-line electron gun, wherein a cross section perpendicular to the cross-section is substantially rectangular having a long side which is flat in the in-line arrangement direction.