JPS5811008Y2 - cathode ray tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cathode ray tube, and particularly to an improvement in the structure for supplying voltage to an electron gun.

The final anode of an electron gun used in a cathode ray tube usually contains 10
A high voltage of several kilovolts or more is applied.

For example, in a pi-potential type electron gun of a commonly used color picture tube, the voltage applied to each electrode is, for example, 25 K to the final anode 1, as shown in FIG.
V is supplied, and 3.8 KV is supplied to the front electrode which together with this electrode constitutes an electron lens.

In addition, in the figure, 11 is an electron gun. The voltage supplied to this final anode 1 is usually as shown in FIG.
High voltage terminal of funnel 2 (hereinafter referred to as high voltage button)
3.

In FIG. 2, 21 is a neck portion, 22 is a face portion, and the face portion 22 has a fluorescent surface 22a formed on its inner surface.

This high voltage is supplied to the final anode 1 of the electron gun through an internal conductive film (hereinafter referred to as internal graphite) 4, but conduction between the internal graphite 4 and the final anode 1 of the electron gun is established through a metal conductive piece 5 within the neck portion 21. This is done as shown in FIG.

In such a configuration, there is no problem in high-voltage conduction through the metal conduction piece 5 under normal conditions, but sparks or the like may occur in the pipe for some reason, causing the contact between the metal conduction piece 5 and the inner graphite 4 to When excessive current flows, the internal graphite part is damaged and fine graphite powder is scattered.

Fine graphite powder causes sparks inside the tube, and once the fine powder scatters, it becomes more likely to cause sparse inside the tube.

Further, when the electron gun 11 is disposed inside the neck tube 21, the electron gun 11 is inserted along the inner wall of the neck tube 21.

At this time, the metal conductive piece 5 inevitably scrapes the interior graphite 4 and generates fine powder.

This fine powder scatters when an excessive current flows through the part, and similarly causes sparks inside the pipe.

What is even more inconvenient is that when sparks occur inside the tube, damage to the contact area between the metal conductive piece 5 and the internal graphite 4 is accelerated due to excessive current, and it becomes more likely to generate fine powder, which in turn becomes more likely to generate sparks. It is.

Furthermore, in a structure in which many strong electric fields are formed inside the neck tube, this tendency is strong and there are many problems.

The present invention provides an excellent cathode ray tube that overcomes the drawbacks of the conventional structure.

Hereinafter, the present invention will be explained according to examples.

FIG. 4 shows an embodiment of the present invention.

The electron gun 11 is supported and fixed by a supporter 15a forming a part of the conductive structure 15, which will be described later, and other supports not shown.

Therefore, the supporter 15a is arranged so as not to come into contact with the interior graphite 4 formed on the inner wall surface of the funnel.

Electrical continuity is provided by the electron gun 11 disposed within the neck portion 21.
One end is fixed to the funnel part 22 from this one end.
A contact portion 15b is provided at the other end of the conductive structure 15 made of a metallic elastic strip extending along the inner wall surface of the funnel, and by directly contacting the contact portion 15b with the high voltage button 3, It is done.

Therefore, even if sparks or vibrations are generated elsewhere for some reason, fine powder such as graphite powder will not be generated at the contact area between the two, and even if it occurs, the neck tube where a strong electric field is formed will not be generated. Since it is difficult for a relationship to occur between the two, the possibility of causing a spark is reduced.

FIG. 5 shows another embodiment of the present invention.

One end of the conductive structure 25 made of a metal elastic strip is attached to the final anode 1 of the electron gun 11, and the other end passes through the funnel section and is near the high voltage button 3 (in this case, near the high voltage button 3). Nearby means a radius of about 50 to 1QQmm around this point.
The contact portion 25b is brought into contact with the metal plate-shaped terminal 16 attached to the high-voltage button 3 to establish electrical continuity.

Further, instead of the plate-shaped terminal 16, the inner wall surface of the funnel of the high voltage button may be metalized over a certain extent for convenient conduction and to prevent the interior graphite from being exposed.

In the figure, reference numeral 17 denotes supports, and in this example, all the supports 17 are constructed separately from the conductive structure 25.

However, depending on the type of ball, one or more of the supports may be brought into contact with the inner graphite.

FIG. 6 shows still another embodiment of the present invention, in which the high-pressure button 3 is provided with a protrusion, a hole is provided in the metal plate 26, and the button is secured with a support 27 such as a bush nut. It shows.

With this structure, conduction in high-voltage parts can be achieved through metal-to-metal contact, eliminating the risk of fine powder such as graphite being generated inside the pipe due to sparks, and making the pipe extremely stable in terms of withstand voltage. .

In the above description, the conductive structure is made into a strip, but it is not limited to this, and it goes without saying that it may be a line or a plate shape whose width, thickness, etc. are partially or completely bordered.

It goes without saying that the present invention is not limited to color picture tubes.

Furthermore, if the contact portion on the funnel side of the conductive structure is divided into multiple branches, the reliability of the connection can be increased.

As described above, according to the present invention, the electrical connection between the high voltage button and the electron gun is made in the funnel part instead of the neck part, and the contact parts of both are made of metal, and furthermore, the electron gun is supported. By reducing the contact between the fixing support and the graphite interior, it is possible to suppress the generation of sparks within the tube, making it possible to create an excellent cathode ray tube with improved withstand voltage.

[Brief explanation of the drawing]

Fig. 1 is a route diagram for explaining an example of the voltage applied to the electrodes of the electron gun of a cathode ray tube, Figs. 2 and 3 are cross-sectional views showing the conventional structure, and Figs. 4 to 6 are the diagrams of the present invention. FIG. 2 is a cross-sectional view of main parts showing an example. 2...Funnel, 3...High voltage terminal,
4... Internal conductive film, 11... Electron gun,
15.25... Conductive structure.

Claims (1)

[Scope of utility model registration request] An envelope having a face portion having a fluorescent surface, a net portion containing an electron gun disposed opposite to the fluorescent surface, and a funnel-shaped funnel portion connecting the neck portion and the face portion. In a cathode ray tube comprising a high voltage terminal provided in a part of the funnel portion of the envelope, an electrical connection between the high voltage terminal and the electron gun is established by fixing one end thereof to the electron gun. , and the other end is formed by a metallic elastic structure that elastically contacts a high voltage terminal of the funnel portion or a conductive contact portion provided in the vicinity of the high voltage terminal and electrically connected to the high voltage terminal. Cathode ray tube.