JPS63138630A - Heating system for electron tube - Google Patents

Abstract

PURPOSE:To perform induction heating by a high frequency induction heating coil in a limited manner as well as to avoid applying any heating to an unnecessary part so effectively, by forming a heating system with the high frequency induction heating coil and the metal ring adjoined to this coil and set up concentrically with it. CONSTITUTION:In case of going to perform electron gun heating, namely, gun burning, the metal ring 12 of an electron tube heating system 13 is set to a position being almost opposite to the base side of a metal spring 5. Simultaneously with this, a high frequency coil 11 is set up in the circumference of a neck part of a tube body of an electron tube, for example, a cathode-ray tube body concentrically with this tube body so as to cause it to be situated in a position opposite to an electrode setup part of an electron gun 3, whereby high frequency current-energization is carried out for the coil 11 only. With this constitution, high frequency induction heating by the coil 11 can be done in a limited manner, so that the lowering of service life due to the heating of the metal spring 5, that is, an earier trend of fatigue is avoidable. In addition, such a drawback that a spring property is lost by vibrations is avoided, thus maintenance of the electron gun and feed effectiveness are stably performable over a long period of time.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to electron gun firing, so-called gun firing, which is performed during the exhaust treatment inside the tube body in the manufacturing process of cathode ray tubes, or when performing getter material flying, that is, so-called getter flash treatment. Related to heating devices for electron tubes used in etc.

[Summary of the invention]

The present invention consists of a high-frequency induction heating coil and a metal ring disposed adjacent to and coaxially with the high-frequency induction heating coil, and performs induction heating by the high-frequency induction heating coil in a limited manner to effectively avoid heating of unnecessary parts. .

[Conventional technology]

In electron tubes such as cathode ray tubes, it is necessary to evacuate the inside of the tube to a high degree of vacuum.
As disclosed in Publication No. 85, during the process of manufacturing the electron tube, the electron gun is heated to a high temperature during the exhaust treatment inside the tube, so-called gun firing is performed to remove gas or foreign matter from the electrodes of each part of the electron gun. A method is used to actively discharge and completely exhaust the gas.

Further, after firing the gun, in order to further increase the degree of vacuum inside the tube, a getter material is flown to adsorb the gas remaining in the tube, that is, a getter material container is heated to perform getter flannoneurization.

Figure 4 shows the relationship between the conventional electron tube heating device fi+ and an electron tube that is heated using it, such as a cathode ray tube (2). (3) is accommodated. This electron gun (3
) is composed of, for example, three cathode electrodes and first to fifth grids 61 to G. C is a convergence means provided at the tip of the electron gun (3) so that the three electron beams from the cathode K are converged (concentrated) on the fluorescent surface formed on the inner face of the cathode ray tube body. being done.

Further, this electron gun (3) is provided with a metal spring (5), which is formed on the inner surface of the funnel part of the cathode ray tube (2), and an internal conductive film (6) to which a high voltage (anode voltage) is applied.
For example, G and G2 to which the anode voltage of the electron gun (3) is applied via the spring (5), and further power is supplied to a part of the deflection plate of the convergence means C. At the same time, the electron gun (3) is held on the axis of the neck tube of the cathode ray tube (2). Further, (8) is a getter container in which an ivy material is housed, which is provided at the tip of the electron gun (3) via a spring +7), and this getter container (8) is formed in a ring shape.

The electron tube heating device (1) consists of a metal conductor wire coil, and when performing gun firing, the electron tube heating device (ffi +11), ie, the coil, is placed in the electron gun (3) as shown in FIG. Each electrode 6 of the electron gun (3) is placed on the outer periphery of the neck tube around the
An induced current is generated in the cylindrical electrodes 1 to G, and each electrode is heated by the induced current to, for example, about 800°C, and the inside of the tube is evacuated from the tip-off tube (9) at the base of the neck tube to remove the tip-off tube. (9) is chipped off and sealed.

In addition, when performing a getter flash, an electron tube heating device (1) consisting of a similar high-frequency coil is brought around the area where the getter container (8) is placed, and the getter container (8) is heated by high-frequency induction. The flight of the getter material,
So-called getter sputtering is performed.

However, when performing gun firing or getter flash using such an electron tube heating VW, the metal spring (5) is heated to a high temperature, for example, about 740° C., due to the heating.

Incidentally, in recent years, this type of cathode ray tube, or electron tube, has come to be widely used as a variety of display devices in aircraft, vehicles, etc. In this case, the electron tube is used under conditions in which fairly intense vibrations are continuously applied to it, and in this case, it is exposed to high temperatures. A heated spring suffers from severe fatigue, causing the problem that its spring properties deteriorate early.

For this reason, when heating this kind of electron tube with a gun or a getter flash, a method is used in which a high-frequency heating coil is arranged in a limited manner in a part excluding the spring arrangement part, and each heating is carried out. However, in practice, when using high-frequency heating using this method,
Induction heating also occurs in areas other than the area where the high-frequency coil is arranged, and the situation is such that the heating cannot be reliably performed in a limited manner.

[Problem that the invention seeks to solve]

As described above, the present invention is capable of reliably heating a target portion in a limited manner in an electron tube heating means used for heating an electron gun, i.e., gun firing, or heating a getter material, i.e., getta flaning. To surely avoid the problem of spring fatigue, that is, deterioration of spring properties.

[Means for solving problems]

In the present invention, as shown in FIG.
A heating device for an electron tube is provided by providing a high-frequency induction heating coil αυ for performing high-frequency induction heating by t, and a metal ring (b) having an inner diameter approximately the same as the inner diameter of this coil 0υ on the same axis as this coil 00 adjacent to the high-frequency induction heating coil αυ. make up the side.

When performing electron gun heating, that is, gun firing, the electron tube heating device α is placed at a position where its metal ring (goods) almost faces the base side of the metal spring (5), as shown in Figure 1. At the same time, the high-frequency coil αυ is placed concentrically around the outer periphery of the neck of the electron tube body, for example, the cathode ray tube body, so that the high-frequency coil αυ faces the electrode placement part of the electron gun (3). High frequency energization is carried out only when

In addition, when performing gun firing, as shown in FIG. 2, the electron tube heating device a1 is brought near the getter container (8), and the coil at+ is arranged to face the periphery of the getter container (8). Metal ring 0 is spring (5
) so that it is on the opposite side.

In this way, only the high frequency coil aυ is energized.

[For production]

When performing gun firing or getter flashing using the above-mentioned apparatus a1 of the present invention, the heating of the metal spring (5) could be kept at about 140° C., which does not affect the metal. This is because the high-frequency magnetic field generated by applying high-frequency current to the high-frequency coil Qll due to the arrangement of the metal ring strikes generates an electromotive force at the metal ring (+21). This seems to be due to the suppression of cancellation in the vicinity of the arrangement part.

〔Example〕

The high-frequency induction coil 00 may be configured, for example, by a metal conductor or a pipe-shaped metal conductor, or by a conductor or pipe coated with a heat-resistant material.

In addition, the metal ring punches each have a center hole (12a) as shown in FIG. 3A-H, and have a relatively thick disk shape as shown in No. It can be formed in the form of a thin disk, a cylinder as shown in FIG. 3C, a metal conductor as shown in the third diagram, or a pipe conductor as shown in FIG. 3E.

Further, if necessary, the ring (goods) may have a shape in which a part thereof has pores extending along the axial direction. Further, the metal ring side may be made of, for example, copper Cu which is relatively rich in R conductivity.

In the example shown in FIGS. 1 and 2, the getter container (7) has a structure provided at the tip of the electron gun (3), but in some cases, for example, the funnel part of the cathode ray tube The device of the present invention can also be used in a structure in which the device extends on the inner wall surface of the device.

〔Effect of the invention〕

As described above, in the present invention, by adopting a configuration in which a metal ring (B) is placed at one end of the high-frequency coil 0υ, high-frequency induction heating by the coil O1l can be performed in a limited manner. It is possible to avoid shortening the lifespan of the metal spring (5) due to heating, that is, premature fatigue, and when applied to electron tubes used in aircraft, vehicles, etc., it is possible to avoid disadvantages such as loss of spring properties due to vibration. It is possible to stably hold and power the gun over a long period of time.

[Brief explanation of the drawing]

1 and 2 are sectional views of main parts of the electron tube heating device according to the present invention and its usage state, and FIGS. 3A to 3E are sectional views showing each pair of metal rings of the present invention, FIG. 4 is a sectional view of a conventional device and an electron tube. 0 is a heating device for an electron tube according to the present invention, αυ is a high frequency induction heating coil, and 3 is a metal ring.

Claims (1)

[Scope of Claim] A heating device for an electron tube, comprising: a high-frequency induction heating coil; and a metal ring disposed substantially coaxially with and adjacent to the coil.