JPH06162953A - Electron gun for color cathode-ray tube - Google Patents

Abstract

PURPOSE:To prevent the deformation of a cylindrical electrode in supporting the electrode in insulated state on a vitreous rod via a bracket. CONSTITUTION:Regarding an electron gun where a final accelerating electrode 13 is formed out of a cylindrical body 14 of elliptical cross section and an electric field correcting division 15 laid therein, and the cylindrical body 14 is supported in insulated state on vitreous rods 6 and 7 by means of metal brackets a and 16b, the welded points of the brackets 16a and 16b with the external surface of the cylindrical body 14 are set on a plane extended from the division 15. As a result, the cylindrical body 14, even when subjected to a strong pressing force through the brackets 16a and 16b, becomes free from deformation. Thus, the electrode 13 can be supported on the rods 6 and 7 in insulated stated at high yield without any need of using a complicated jig.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron gun incorporated in a color picture tube to generate an electron beam, and more particularly to an in-line type electron gun.

[0002]

2. Description of the Related Art Generally, an in-line type electron gun is constructed as shown in FIG. That is, three cathodes 1, control grid electrodes 2, which are arranged inline in a direction perpendicular to the plane of the drawing,
An accelerating electrode 3, a focusing electrode 4 and a final accelerating electrode 5,
These electrodes are insulated and supported by a pair of glass rods 6 and 7 provided on both sides thereof. 8 is the top unit,
Reference numeral 9 indicates a metal spring for power supply.

An electrode support structure in which the tip of a tab integrally formed with the end of the electrode is embedded in the glass rod, and an electrode support in which the tip of a metal bracket having the base end welded to the outer surface of the electrode is embedded in the glass rod. There is a structure, and these are properly used according to the shape of the electrode and the like. In the illustrated electron gun, the former is applied to the support structure of the acceleration electrode 3 and the focusing electrode 4, and the latter is applied to the support structure of the control grid electrode 2 and the final acceleration electrode 5.

The final accelerating electrode 5, together with the focusing electrode 4, produces a main lens electric field. It is advantageous in terms of spherical aberration that the diameter of the main lens electric field is as large as possible. In the electron gun disclosed in Japanese Unexamined Patent Publication (Kokai) No. 4-133247 and the like, a cylindrical body having an elliptical cross section is used for the focusing electrode and the final accelerating electrode, and three electron beam passage holes are arranged inline to correct an electric field A partition plate is provided in the cylindrical body.
By using the electrodes thus configured, it is possible to generate three large-diameter main lens electric fields, so that it is possible to obtain an electron gun particularly suitable for a high definition color picture tube. FIG. 4 exemplifies such an electrode structure. The focusing electrode 10 has a partition plate 12 for electric field correction in a tubular body 11 having an oval cross section, and the partition plate 12 passes three electron beams that are arranged in-line. It has holes 12a, 12b, 12c. Also,
The final accelerating electrode 13 has a partition plate 15 for electric field correction in a tubular body 14 having an oval cross section, and the partition plate 15 has three electron beam passage holes 15a, 15b, 15c arranged in-line. .

[0005]

By the way, when the base end of the metal bracket is welded to the outer surface of the electron gun electrode and the tip of the bracket is fixed to the glass rod, the rod is heated to a high temperature. Since the tip of the bracket is pushed into the softened portion, it is easy to deform the electron gun electrode during this step. In particular, since a slight deformation is not allowed in the electrode structure as shown in FIG. 4, various techniques and complicated jigs are required for insulating and supporting the electrodes.

[0006]

According to the present invention, the final accelerating electrode for generating the main lens electric field together with the focusing electrode is formed of a cylindrical body having an oval cross section and an electric field correcting partition plate provided inside the cylindrical body. In an electron gun in which the tubular body is insulated and supported by a glass rod through a metal bracket, a welding point of the bracket to the outer surface of the tubular body is set on an extension plane of the partition plate.

[0007]

With this structure, the partition plate in the process of insulatingly supporting the final accelerating electrode on the vitreous rod plays a role of a core material for supporting the tubular body from its inner surface side. Even if a strong pressing force is applied to the tubular body, the tubular body is not deformed. Therefore, the final accelerating electrode can be insulated and supported on the glass rod with a good yield without using a complicated jig.

[0008]

The present invention will be described below with reference to the illustrated embodiments. The final accelerating electrode 13 shown in FIG. 1 and FIG.
Substantially the same as the one shown in FIG. 1 and is composed of a tubular body 14 having an oval cross section and an electric field correcting partition plate 15 provided therein. The partition plate 15 has three electron beam passage holes 15a, 15b, 15c arranged in-line, and generates three large-diameter main lens electric fields together with a focusing electrode (not shown) adjacent to these electrodes.

Final acceleration is achieved by embedding the tip ends of the two U-shaped brackets 16a, 16b made of metal, the base ends of which are welded to the outer surface of the tubular body 14, in the respective vitreous rods 6, 7. The electrode 13 is insulated and supported, but two brackets 16 for the outer surface of the tubular body 14 are provided.
Each welding point of a and 16b is set on the extension plane of the partition plate 15.

Therefore, in the process of insulatingly supporting the final accelerating electrode 13 on the glass rods 6 and 7 on both sides thereof, the partition plate 15 functions as a core material for supporting the cylindrical body 14 from its inner surface side. , Therefore the brackets 16a, 16
Even if a strong pressing force acts on the tubular body 14 through b, the tubular body 14 will not be deformed.

Although the U-shaped bracket is used in the above embodiment, brackets having other shapes can be used. When the bracket has a plurality of welding points with respect to the tubular body, the initial purpose can be achieved if at least one welding point is set on the extension plane of the partition plate.

[0012]

As described above, according to the present invention, even if a strong pressing force acts on the tubular body through the bracket, the tubular body is not deformed, so that the final acceleration is performed without using a complicated jig. The electrodes can be supported on the glass rod in good yield with good insulation.

[Brief description of drawings]

FIG. 1 is a side sectional view of a main part of an electron gun embodying the present invention.

FIG. 2 is a perspective view of the same main part.

FIG. 3 is a partially cutaway side view of a part of a conventional electron gun.

FIG. 4 is a partially cutaway side view of a part of a conventional electron gun.

[Explanation of symbols]

 6,7 Glass rod 13 Final accelerating electrode 14 Cylindrical body 15 Electric field correction partition plate 16a, 16b Bracket

Claims (1)

[Claims] 1. A final accelerating electrode for generating a main lens electric field together with a focusing electrode comprises a cylindrical body having an oval cross section and an electric field correcting partition plate provided therein, and the partition plates are arranged inline. In an electron gun having individual electron beam passage holes, wherein the tubular body is insulated and supported by a glass rod through a metal bracket, the welding point of the bracket to the outer surface of the tubular body is defined by the partition wall. An electron gun for a color picture tube characterized by being set on an extension plane of a plate.