JPS6122539A - Electron gun part - Google Patents

Abstract

PURPOSE:To prevent any deterioration of the characteristic of an electron tube by manufacturing an electron gun part by powder metallurgy using an alloy powder contaning a given amount of Zr or Hf. CONSTITUTION:An electron gun part consists of base crystals 5, an alloy phase 6 composed of Zr and the base, air holes 7 and the like. The Zr component of the alloy phase 6 prevents any decrease in the vacuum degree of the internal atmosphere of a cathode-ray tube by adsorbing th gas emitted when the electron gun part is heated to high temperature. The electron gun part should be manufactured under sufficient supervision in order to prevent any decrease in the getter performance which might be caused when a relatively small amount of Zr or Hf contained in the getter is oxidized during manufacture or preservation. Consequently, it is possible to prevnt any deterioration of the characteristic of the electron tube.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention provides an electron tube using this electron gun component, which releases little gas even when used in a high vacuum, heated to high temperatures, or exposed to electron bombardment. This invention relates to electron gun parts that do not deteriorate the characteristics of the electron gun.

[Background of the invention]

In recent years, among the parts of electron guns used in the high-vacuum envelope of mass-produced electron tubes, such as cathode ray tubes, parts that require rigidity or shape retention and have somewhat complex shapes are manufactured using powder metallurgy. Things are starting to be tried.

This is because, in the case of mass-produced products, if you try to make parts with thicker walls and higher rigidity than press parts etc. by machining, it will be expensive, and it is cheaper to make it by powder metallurgy. Because it came.

However, parts made using this type of powder metallurgy are different from wire rods, which have a simple shape and can be swaged easily.
If pores inevitably remain inside the tube and are heated to high temperatures or exposed to electron bombardment, the gas stored inside the pores will be released and the degree of vacuum inside the tube will decrease, making it impossible to use the parts again. There was a problem in that the performance of the electron tube deteriorated. Therefore, conventionally, parts made by powder metallurgy have been used only in limited areas such as areas where the temperature rise is small.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide an electron gun component manufactured by powder metallurgy that does not cause the problems of the conventional products described above.

[Summary of the invention]

In order to achieve the above object, in the present invention, electron gun parts are manufactured by powder metallurgy using an alloy containing 0.1 to 10% by weight of Zr or Hf in its raw material powder. .

As is well known, Zr and Hf have good gas adsorption performance, so-called gettering performance, so that the electron gun parts themselves can immediately adsorb gas that is about to be released from residual pores at high temperatures. Suppresses the release of gas into the space inside the electron tube and prevents the vacuum level inside the tube from decreasing.
This makes it possible to prevent deterioration of electron tube characteristics.

The content of Zr and Hf was set to 0.1 to 10% by weight because
If the content is less than 0.1%, a sufficient gettering effect cannot be obtained, and if the content is more than 10%, the self-shape maintenance property when a large amount of gas is adsorbed becomes insufficient (it becomes crumbly). This is because it will be put away.

[Embodiments of the invention] FIG. 1 schematically shows the electron gun portion of a cathode ray tube.

In the figure, 1 is a heater, 2 is a cathode, 3 is a glass bulb,
4 is an electron gun component.

The electron gun component 4 shown in FIG. 1 forms an electrostatic lens that focuses the electron flow emitted from the cathode 2 into a narrow beam, and has conventionally been manufactured by pressing a plate material. However, parts manufactured in this way do not have sufficient rigidity, and when they are hit by some of the electrons from the electron beam passing through the electrostatic lens and heated to high temperatures, they deform. Therefore, it was considered that these electron gun parts should be made into a so-called block structure with a wall thickness of 1 mm or more. If they were made by machine cutting from thick plates or bars, it would require a large amount of man-hours and the performance would be good (but the price would be very high. Therefore, powder metallurgy However, since the powder material is manufactured by pressure sintering, it is inevitable that some pores will remain, and the high temperature heating caused by the bombardment of the electrons will cause the pores to disappear. It has been recognized that the storage gas is released, lowering the degree of vacuum inside the cathode ray tube in which this component is used, deteriorating its characteristics, and in particular significantly shortening its life.

In order to deal with these problems, a cathode ray tube was fabricated using parts according to the present invention, and no deformation of the parts was observed. No deterioration in release characteristics or short life was observed.

FIG. 2 is an enlarged cross-sectional view of an electron gun component according to the present invention.
is a base crystal, 6 is an alloy phase of Zr and the base, and 7 is a vacancy. . This alloy phase of Zr adsorbs the gas that is about to be released when the component is heated to a high temperature, thereby preventing the degree of vacuum inside the cathode ray tube from decreasing.

In addition, when manufacturing electron gun parts implementing the present invention,
It is necessary to perform sufficient management to prevent getter performance from decreasing due to oxidation of the getter components Zr and Hf, which have relatively low contents, during the manufacturing process of the parts themselves or during subsequent storage. It is.

〔Effect of the invention〕

As explained above, according to the present invention, gas emission from electron gun parts manufactured by powder metallurgy is substantially prevented, and it can be put to practical use even in parts such as electrostatic lens parts that do not like deformation and are heated to high temperatures. It becomes possible to provide

[Brief explanation of drawings]

Claims (1)

[Claims] Electron gun parts used in high vacuum, manufactured by powder metallurgy, with 0.1 to 0.1 to
An electron gun component characterized by using an alloy containing 10% by weight.