JPH0218539B2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field of the Invention The present invention relates to an electron gun assembly and a manufacturing method thereof;
In particular, the present invention relates to an electron gun assembly that can be assembled effectively by changing the diameter of an electron beam passage hole in a grid constituting the electron gun assembly, and a method for manufacturing the same.

Technical Background of the Invention Electron gun structures used for color picture tubes include unipotential electron gun structures (hereinafter referred to as UPF) and bipotential electron gun structures (hereinafter referred to as UPF).
However, these UPF and BPF had advantages and disadvantages, and it was difficult to reduce the spots on the screen of a color picture tube over the entire surface.

As a countermeasure to this problem, the applicant first developed an electron gun structure (hereinafter referred to as QPF) that uses a unipotential type electron lens as an auxiliary electron lens and a bipotential type electron lens as the main electron lens. The spots are made smaller over the entire surface, making it possible to obtain extremely clear reproduced images with high brightness and high contrast.

Next, the main part of the structure of this QPF will be explained with reference to FIG. That is, the QPF 1 includes a cathode 3 with a heater 2 installed inside, a first grid 4, and a second grid 5, 2.
A third grid 6 consists of two cap-shaped electrode elements 6 ₁ , 6 ₂ and one flat electrode element 6 ₃ , a fourth grid 7 consists of two cap-shaped electrode elements 7 ₁ , 7 _{2 ,} and a fourth grid 7 consists of two cap-shaped electrode elements 7 1 , 7 2 . A first assembly 8a consisting of cap-shaped electrode elements 8 ₁ and 8 ₂ and one plate-shaped electrode element 8 ₃ ;
and a second assembly 8b consisting of two cap-shaped electrodes 8 ₄ , 8 ₅ and one flat electrode element 8 ₆ , two cap-shaped electrode elements 9 ₁ , 9 ₂ and a sixth grid 9 consisting of one flat electrode element 9 ₃ , these heaters 2,
Cathode 3, first grid 4, second grid 5, third
grid 6, fourth grid 7, fifth grid 8,
The sixth grids 9 are installed on the insulating support rods 10 through the installation portions at predetermined intervals, and the third
The grid 6, the fourth grid 7, and the fifth grid 8 form a unipotential type electron lens, and the fifth grid 8 and the sixth grid 9 form a bipotential type electron lens.

The electron gun assembly shown in FIG. 1 is assembled by the assembly method shown in FIGS. 2 to 4. In the figure, the same parts as in FIG. 1 are denoted by the same reference numerals.

First, as shown in FIGS. 2 and 3, an assembly jig 1 is prepared in which a center rod 12 for positioning is installed on a surface plate 11.
A cap-shaped electrode element 8 ₄ that does not constitute an electron lens, a flat electrode element 8 ₆ , and a cap-shaped electrode 8 ₅ that forms an electron lens are inserted into the cap-shaped electrode 8 5 in this order from above the cap-shaped electrode 8 ₅ through the jig 14. Positioning jigs 15, 16, 17, 18, 19 provided on the assembly jig 13 while pressing with a force (F ₃ ) in the direction of the arrow
The positions of the four reference planes 20 provided on the outer periphery of the flat electrode element ₈₆ and the center rod 12 are determined using the following. In this case, as shown in the figure, the positioning jig 18,
Forces (F ₁ ) (F ₂ ) are applied to the flat electrode element 8 ₆ in the direction of the arrows through springs or the like, respectively. Next, the cap-shaped electrode element 8
₄ , ₈₅ and the flat electrode element ₈₆ are subjected to resistance welding or laser welding at the welding point 21 to complete the second assembly 8b. This manufacturing method is applied to the first grid of the third grid 6, fourth grid 7, and fifth grid 8.
The same applies to the assembly 8a and the sixth grid 9.

Next, the assembly of the electron gun assembly will be explained with reference to FIG. In the figure, the same reference numerals as in FIG. 1 indicate the same parts, and no particular explanation will be given.

That is, the sixth grid 9, the spacer 24, and the fifth grid 8 are attached to the center rod 23 installed on the surface plate 22.
The second assembly 8b, the first assembly 8a, the spacer 25, the fourth grid 7, the spacer 26, the third grid 6, the spacer 27, the second grid 5, the spacer 28, and the first grid 4 are stacked in this order, A jig 29 is placed on this first grid 4, and while tightening with force (F ₄ ) in the direction of the arrow, the insulation support rods 10 with softened surfaces are pressed against both sides, and the implanted portion of each grid is attached to this insulation support. Planted on the rod 10, center rod 23, each spacer 24, 25, 26, 27, 2
8 is removed, and the electron gun assembly shown in FIG. 1 is completed. In FIG. 4, the cathode and heater are omitted.

The shape of each grid of the electron gun assembly assembled by the above-described manufacturing method, for example, the first assembly 8a, second assembly 8b, and sixth grid 9 of the fifth grid 8, is the same as that of the second assembly 8b. As shown in FIG. 5, the diameter (φ 1 ) of the electron beam passage hole of the cap-shaped electrode element 8 ₅ constituting the electron lens, and the diameter (φ ₁ ) of the electron beam passage hole of the flat electrode element 8 _{6 2} ) The diameter (φ ₃ ) of the electron beam passage hole of the cap-shaped electrode element 8 ₄ that does not constitute an electron lens was formed to be the same.

Problems with the Background Art As described above, since the diameters (φ ₁ ), (φ ₂ ), and (φ ₃ ) of the electron beam passage holes of each element are the same, the following problems occur.

First, it is difficult to automate part accuracy measurement. In other words, optical measurement using transmitted light is the easiest method to automate, but flat electrode elements 8 ₆
Apart from this, since the cap-shaped electrode elements 8 ₅ and 8 ₄ have the same diameter, for example, even if parallel light is passed through the cap-shaped electrode element 8 ₅ from outside, this light will not pass through the electron beam of the cap-shaped electrode element 8 ₄ . This type of optical measurement cannot be used because a clear image cannot be obtained because a portion of the image is blocked by the hole.

The productivity of the second electron gun assembly is poor. That is, the fourth
In the so-called beading process shown in the figure, the center rod 2 is used as a grid or as an assembly of the grid.
3, the workability when inserting these grids or grid assemblies into the center rod is poor.

Thirdly, the assembly accuracy of the electron gun assembly is deteriorated.
As shown in the figure, in the beading process, the 6th grid 9
cap-shaped electrode element 9 ₁ constituting the electron lens of
If a modified one as shown in the figure is used, the second assembly 8 of the fifth grid 8 is connected via the spacer 24.
Considering the case where the cap-shaped electrode elements 8 ₄ and 8 ₅ of the second assembly 8b and both the cap-shaped electrode elements 9 ₁ and 9 ₂ of the sixth grid 9 are placed, the electron beam passage holes The portions have the same diameter, and these slide onto the center rod 24, and a force (F ₄ ) is applied from above in the direction of the arrow.
As a result, the spacer 24 and the cap-shaped electrode element ₈₅ contact each other only at a point 31, and a stress as indicated by an arrow 32 is applied to the second assembly 8b, and the center rod 23 is pressed at points 33 and 34. Since the second assembly 8b moves when removed from the center rod 23 after the beading process, it is likely to become defective as an electron gun assembly.

Fourth, the accuracy of electron gun structure alignment measurement deteriorates. In other words, electrode elements that do not constitute an electron lens that does not require precision, electrode elements 8 ₄ and 9 ₂ in Figure 6 that constitute an electron lens that requires precision, and electron beam passing holes 8 ₅ and 9 ₁ in Figure 6 Since the parts are the same, both the contact type and the optical type interfere with measurement, resulting in deterioration of measurement accuracy.

Fifth, the focus quality deteriorates.In other words, since the diameters of the electron beam passage holes are the same, if the electron beam passage hole of the electrode element that does not constitute the electron lens is off-center, the electric field that forms the electron lens will This causes distortion in the electron beam passing through the electron lens, deteriorating the focus quality.

Object and Structure of the Invention The present invention has been made in view of the problems of the above-mentioned background art. By making the diameter of the electron beam passage hole of the electrode element that does not constitute the electron lens larger, for example, by 0.04 to 0.30 mm, than the diameter of the electron beam passage hole of the electrode element that constitutes the electron lens, automation of parts accuracy measurement and productivity and assembly accuracy can be improved. The object of the present invention is to provide an electron gun assembly that can be expected to improve alignment measurement accuracy and focus quality, and a method for manufacturing the same.

Embodiment of the Invention Next, the main part of the structure of a QPF as an embodiment of the present invention will be explained with reference to FIG.

That is, the QPF 41 includes a cathode 43 with a heater 42 installed inside, a first grid 44, and a second grid 4.
5. Two cap-shaped electrode elements 46 ₁ , 46 ₂ and 1
A third grid 46 consists of three plate-shaped electrode elements 46 ₃ , a fourth grid 47 consists of two cap-shaped electrode elements 47 ₁ , 47 ₂ , a fourth grid 47 consists of two cap-shaped electrode elements 48 ₁ , 48 ₂ and one Flat electrode element 48 ₃
and a second assembly 48b consisting of two cap-shaped electrode elements 48 ₄ , 48 ₅ and one plate-shaped electrode element 48 ₆ , It is equipped with a sixth grid 49 consisting of two cap-shaped electrode elements 49 ₁ , 49 ₂ and one plate-shaped electrode element 49 ₃ , and includes a heater 42 , a cathode 43 , a first grid 44 , a second grid 45 , 3rd grid 46, 4th grid 4
7, the fifth grid 48 and the sixth grid 49 are respectively planted on the insulating support rod 50 via the planting portions at predetermined intervals, and the third grid 46, the fourth grid 47 and the fifth grid 48 form a unit. It is almost the same as the conventional one in that a potential type electron lens is formed and a bipotential type electron lens is formed by the fifth grid 48 and the sixth grid 49, but in this embodiment, these grids are and electrode elements 48 ₂ , 48 ₃ , 48 ₄ that do not constitute an electron lens in the assembly,
The diameters of the electron beam passing holes 48 ₆ , 49 ₃ , 49 ₂ are the same as those of the electrode elements 48 ₁ , 48 ₅ , which constitute the electron lens.
It is characterized in that the diameter is larger than the diameter of the electron beam passage hole of _{No. 491} , and the degree of this enlargement is 0.04 to 0.30.

Next, a method of assembling the grid, assembly, etc. will be explained with reference to FIGS. 8 and 9.

That is, a cap-shaped electrode element 48 4 and a plate-shaped electrode element that do not constitute an electron lens are attached to an assembly jig 53 in which a center rod 52 for positioning having a large diameter part 52 ₁ and a _small diameter part 52 ₂ is implanted in a surface plate 51. 48 ₆ and the cap-shaped electrode element 48 ₅ constituting the electron lens, and insert the jig 5 from above the cap-shaped electrode element 48 ₅ .
4, the positioning jig 55 is attached to the assembly jig 53 while being pressed with a force (F ₃ ) in the direction of the arrow.
56, 57, 58, and 59, and four reference planes 60 provided on the outer periphery of the flat electrode element _486.
and determine the position of the center rod 52. In this case, as shown in the figure, the positioning jigs 58 and 59 are provided with springs, etc., in the directions of the arrows (F ₁ ) and (F ₂ ), respectively.
force is applied to the flat electrode ₄₈₆ . Next, the cap-shaped electrode elements 48 ₄ , 48 ₅ and the plate-shaped electrode element 48 ₆ are subjected to resistance welding or laser welding at the welding point 61 to form the second assembly 48b.
is completed. This manufacturing method includes the first assembly 48
The same applies to the sixth grid 9. The other grids are assembled by the same manufacturing method as that of FIG.

A grid having such a structure is assembled as an electron gun assembly in a manner similar to that shown in FIG. For example, in the second assembly 48b of the fifth grid 48, as shown in FIG. 10, the diameter of the electron beam passage hole of the cap-shaped electrode element ₄₈₅ constituting the electron lens is set to ₁ ), the diameter (φ ₄ ) of the electron beam passage hole of the flat electrode element 48 ₆ and the cap-shaped electrode element 48 ₄ that does not constitute an electron lens.
(φ ₅ ) is formed large, for example, when φ ₁ =3.9 mm, (φ ₄ )(φ ₅ )=4.0 mm.

The electron gun assembly constructed in this manner has the following advantages.

First, it is possible to automate parts accuracy measurement. That is, since the diameter of the electron beam passage hole constituting the electron lens is the minimum diameter, optical measurement using transmitted light becomes possible with high precision.

Second, the productivity of the electron gun assembly is improved. That is,
In the beading process, only the electrode elements that make up the electron lens slide onto the center rod, allowing for smooth component insertion.

Thirdly, the assembly accuracy of the electron gun assembly is improved. That is, when the cap-shaped electrode element ₄₉₁ constituting the electron lens of the sixth grid 49 is deformed as shown in the figure in the beading process as shown in FIG. When the second assembly 48b is placed, the cap-shaped electrode element 48 ₄ and the flat electrode element 48 ₆ of the second assembly 48b have large electron beam passage holes;
The cap-shaped electrode element 48 ₅ and the cap-shaped electrode element 49 ₁ contact the spacer uniformly, so that the assembly accuracy can be maintained without affecting the electron lens formed between the cap-shaped electrode element 48 ₅ and the cap-shaped electrode element 49 _1. improves.

Fourthly, the accuracy of electron gun structure alignment measurement is improved. That is, the measurement accuracy is improved because the electron beam passage hole of the electrode element that does not constitute the electron lens does not interfere with the measurement.

Fifth, focus quality is improved. That is, even if an electrode element that does not constitute an electron lens is off-center, the diameter of its electron beam passage hole is large, so the electric field forming the electron lens is not disturbed, so the distortion of the electron beam is eliminated, and the focus quality is improved.

In the above embodiment, a QPF was used as the electron gun structure, but this is not limited to QPE and can be applied to UPF and BPF as well. Although a case has been described in which a cylindrical so-called burring is used in the passage hole portion, the present invention is not limited to this, and one side may be a flat electrode element. Furthermore, as shown in FIG. 12, instead of the flat electrode element, a flat metal plate 48 ₇ used only for the implanted portion may be used, or as shown in FIG. 13, both cap-shaped electrode elements 48 ₄ , ₄₈₅ can be extended to serve as the implanted part ₄₈₈ , or the implanted part ₄₈₉ can be fixed to the outer periphery of the cap-shaped electrode element ₄₈₄ as shown in FIG. 14, or as shown in FIG. The same applies to the case where an implanted portion ₄₈₁₀ is further provided on the top surface of the cap-shaped electrode element ₄₈₄ . However, Figures 12 to 1
The same reference numerals in FIG. 5 as in FIG. 10 indicate the same parts or the same diameters, and will not be particularly described.

Effects of the Invention As described above, according to the electron gun assembly of the present invention, the diameter of the electron beam passage hole of the electrode element that does not constitute the electron lens is larger than the diameter of the electron beam passage hole of the electrode element that constitutes the electron lens. By doing so, it is possible to automate parts accuracy measurement, improve productivity, improve assembly accuracy, improve alignment measurement accuracy, and improve focus quality, so its industrial value is extremely large.

[Brief explanation of drawings]

1 to 5 are diagrams showing the electron gun assembly of the prior application and its manufacturing method, in which FIG. 1 is a sectional view of the electron gun assembly, FIG. 3 is a sectional view of FIG. 2 taken along the line A-A, FIG. 4 is an explanatory diagram of the method for manufacturing the electron gun assembly, FIG. 5 is a sectional view of the assembly, and FIG. 6 is a sectional view of the assembly. FIGS. 7 to 10 are explanatory cross-sectional views showing one of the problems of the prior application, and FIGS. 7 to 10 are views showing the electron gun assembly and its manufacturing method of the present invention. FIG. FIG. 8 is a plan view showing the manufacturing process of the assembly, FIG. 9 is a cross-sectional view of FIG. 8 taken along line B-B,
FIG. 10 is a sectional view of the assembly, FIG. 11 is an explanatory sectional view showing one of the advantages of this embodiment, and FIGS. 12 to 15 are assemblies applicable to other embodiments of the present invention. FIG. 2,42...Heater, 3,43...Cathode, 4,
44...First grid, 5,45...Second grid, 6,46...Third grid, 7,47...Fourth grid, 8,48...Fifth grid, 8a,
8b, 48a, 48b...assembly, 9,49...
6th grid, 12, 23, 52...center rod.

Claims (1)

[Scope of Claims] 1. At least one grid comprising a plurality of grids and other electrodes, at least one of the grids positioning and assembling two electrode elements, each of which is provided with an electron beam passage hole. In an electron gun assembly comprising an assembly in which the plurality of grids and other electrodes are implanted on an insulating support rod via implantation portions, an electron beam passage hole provided in the assembly, An electron gun assembly characterized in that the diameter of the electron beam passing hole of the electrode element not forming the electron lens is larger than the diameter of the electron beam passing hole of the electrode element forming the electron lens. 2. The electron gun assembly according to claim 1, wherein the degree of increase is 0.04 to 0.3 mm. 3 consisting of a plurality of grids and other electrodes, at least one of said grids consisting of at least one assembly in which two electrode elements each provided with an electron beam passage hole are positioned and assembled; In a method for manufacturing an electron gun assembly in which a plurality of grids and other electrodes are implanted on an insulating support rod via implantation parts, an electron lens constitutes one of the two electrode elements constituting the assembly. forming the diameter of the electron beam passing hole of the electrode element that does not constitute the other electron lens to be larger than the diameter of the electron beam passing hole of one of the electrode elements; and assembling and fixing the two electrode elements. 1. A method for manufacturing an electron gun assembly, comprising at least the steps of: and stacking the plurality of grids and other electrodes via a spacer and a center rod.