JPS63198239A - Electron gun structure for cathode ray tube - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electron gun assembly for a cathode ray tube in which the main V lens diameter is made as large as possible to improve focus characteristics.

[Conventional technology]

Various types of electron gun assemblies for cathode ray tubes are used, but the electron gun assembly shown in FIG. 3 has first to sixth electrodes 1 to 6 approximately coaxial with the cathode electrode. Of these electrodes 1 to 6, the first to fifth electrodes are held insulated from each other by an insulating support rod 7. 8 is a support whose one end 8a is connected to the fourth electrode 4, and the other end 8b is connected to the fourth electrode 4. is the 6th
Electrode 6 (This is a support that is fixed to each and holds the sixth electrode and measures electrical continuity. This support 8
There are multiple pieces distributed evenly around the circumference.

In the electron gun assembly having such a structure, an anode voltage is applied to the sixth electrode E via a spacer contact (not shown), and a voltage of - several times the anode voltage is applied to the fifth electrode E.
A focus voltage of is applied.

An example of an electron gun for partially overlapping electrodes is disclosed in Japanese Patent Application Laid-Open No. 147942/1983, for example.

[Problems that the invention is likely to solve]

In the electron gun assembly as shown in FIG. This is a structure in which V/Z is formed, but the diameter of the fifth electrode 5 is increased to form a sixth electrode.
When the distance between the electrodes '# and the electrode 6 is made smaller, the fifth electrode 5
There is a problem with the withstand voltage characteristic that discharge is likely to occur between the end 5a on the fluorescent surface (not shown) side of the device and the sixth electrode 6.

In order to solve this problem, a knocking process is performed in which a voltage much higher than the normal operating state is applied to the sixth electrode 6 to bring the sixth electrode 6 and the fifth electrode 5 into a stable state against discharge. Problems remained in the treatment of the end portion 5a, and the problem of withstand voltage characteristics was not sufficiently solved.

An object of the present invention is to provide an electron gun assembly capable of sufficiently knocking the end portion 5a to prevent discharge between the fifth electrode 5 and the sixth electrode.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention provides a structure in which a sixth electrode (a protrusion) is provided opposite the end 5a of the fifth electrode.

[Function] Since the protrusion is provided on the sixth electrode opposite to the end of the fifth electrode, the end of the fifth electrode acts to concentrate the electric field. By applying a high voltage, a knocking effect is obtained between the end portion of the fifth electrode and the protruding portion of the sixth electrode, and the surface treatment of the end portion becomes possible, and the withstand voltage characteristics in a steady state of operation are improved.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG.

In FIG. 1, the same parts as in FIG. 3 are given the same symbols and detailed explanations will be omitted. FIG. 1 (herein, 16 is an annular body, this annular body 16 is arranged and fixed inside the sixth electrode 6, facing the end 5ai of the fifth electrode 5, and has a protrusion opposite to the end 5af). It makes up the department.

FIG. 2 shows another embodiment of the present invention, in which an annular body 26 is fixed to the inside of the sixth electrode 6 facing the end 5a, forming a protrusion.

The annular body 16.26 shown in FIG. 1 and FIG. The spacing between the cylindrical portions of the electrodes 5 is set as follows.

Further, in the above-described embodiment, an annular body separate from the sixth electrode 6 was provided, but the sixth electrode 6 itself may be deformed to form a protrusion that protrudes inward, and the protrusion may be formed at the end. Part 5
It does not need to cover the entire circumference of a as long as the knocking effect can be obtained.

In the embodiments shown in FIGS. 1 and 2, the protrusion is provided over the entire circumference of the end portion 5a, so that distortion occurs in the electrostatic V-lens formed between the fifth electrode 5 and the sixth electrode 6. In addition, the diameter of the V-lens is the same as that of the conventional one, and the end portion 5
This has the effect of concentrating the electric field during knocking over the entire circumference of a.

〔Effect of the invention〕

According to the present invention, it is possible to concentrate the electric field at the end of the fifth electrode at the time of knocking and treat the end, thereby preventing the generation of sparks during steady operation, and maintaining a large diameter lens. It is possible to obtain excellent withstand voltage characteristics.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway sectional view of an electron gun assembly showing one embodiment of the present invention, FIG. 2 is a sectional view of essential parts of an electron gun assembly showing another embodiment of the invention, and FIG. 3 is a conventional one. FIG. 2 is a partially cutaway sectional view showing an example of an electron gun assembly. K... Cando electrode, 1... First electrode, 2
...Second electrode, 3...Third electrode, 4...
- Fourth electrode, 5... Fifth electrode, 6... Sixth electrode, 7... Insulating support rod, 8... Support, 16.26... Annular body.

Claims (1)

[Claims] 1. A cathode electrode, a plurality of grid electrodes arranged coaxially with the cathode electrode, an outer grid electrode to which a high voltage is applied, which is arranged on the terminal side of the plurality of grid electrodes, and this outer grid electrode. and an inner grid electrode adjacent to the inner grid electrode and having at least one end disposed within the outer grid electrode, the outer grid electrode protruding to a position opposite to the one end of the inner grid electrode. An electron gun assembly for a cathode ray tube, characterized in that it has a section.