JPH0352166B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an electron tube exhaust method suitable for use, for example, in exhausting an image pickup tube.

[Technical background of the invention and its problems]

Conventionally, when releasing gas from metal parts such as electrodes during the exhaust process during the manufacture of electron tubes, such as image pickup tubes, a coil was wound around the outer periphery of the glass envelope and a high frequency current was passed through the glass envelope to heat it. Further, gas release from the wall of the glass envelope was accomplished by placing an electron tube in a baking furnace such as an electric furnace or a gas furnace and heating it.

However, as mentioned above, in the conventional exhaust method, gas release from metal parts and gas release from the glass envelope wall must be performed separately or simultaneously using large-scale equipment, making the process complicated and difficult to manufacture. It is inefficient and requires a large baking oven.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for evacuating an electron tube that can simultaneously release gas from metal parts and from the wall of a glass envelope, and which does not require a baking oven.

[Summary of the invention]

This invention provides an insulating cylinder whose inner surface is coated with a heat reflective film having a cut in a part in the circumferential direction, an insulating cylinder having an inner surface coated with a heat reflecting film having a cut in a part in the circumferential direction, an insulating cylinder provided inside a high-frequency coil, an exhaust electron tube disposed inside the insulating cylinder, and the above-mentioned This is an electron tube exhaust method in which a high-frequency current is passed through the coil to heat it, and gas is discharged from the glass envelope wall at the same time by utilizing radiant heat from the metal parts of the electron tube and reflected heat from the heat-reflecting film. .

[Embodiments of the invention]

The electron tube exhaust method according to the present invention utilizes residual heat from the heating process of metal parts and simultaneously performs the heating process of the glass envelope wall.
It is configured as shown in the figure.

That is, an insulating cylinder 3 made of glass, for example, is provided inside a high-frequency coil 2 whose both ends are connected to a high-frequency power source 1. A heat reflective film 4 made of Cr or Al is coated on the inner surface of the insulating cylinder 3, as shown in FIG. 2, in order to shield and reflect radiant heat. This has a cut 5 of a small size formed in a part in the circumferential direction. This cut 5 prevents the generation of current in the film itself due to high frequency, and prevents the film itself from generating heat.

To exhaust an electron tube, for example, an image pickup tube, the image pickup tube 6 is housed in the insulating cylinder 3, and a high-frequency current is passed through the high-frequency coil 2 to exhaust metal parts 7 such as desired electrodes inside the image pickup tube 6 . Perform high frequency heating. Then, gas is released from the metal part 7. At this time, the radiant heat emitted from the metal part 7 is reflected by the heat reflecting film 4 of the insulator cylinder 3, and thereby the insulator cylinder 3
The glass envelope 8 of the image pickup tube 6 housed inside is also effectively heated, and gas is released from the wall of the glass envelope 8 at the same time.

〔Effect of the invention〕

According to this invention, the wall of the glass envelope 8 can be simultaneously heated using the radiant heat emitted from the metal part 7 by high-frequency heating, so the exhaust process is simplified, the efficiency is excellent, and a baking oven is not required. becomes. Needless to say, the configuration is simple. By appropriately positioning the heat-reflecting film, it is possible to suppress heating of, for example, the photoelectric conversion target portion of the image pickup tube, and to heat only the predetermined electrode and envelope portions and cause gas to be released therefrom.

In the above embodiment, the image pickup tube 6 was used as an example of the electron tube, but the present invention is also applicable to exhausting electron tubes other than the image pickup tube 6 .

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an electron tube evacuation method according to an embodiment of the present invention, and FIG. 2 is a perspective view showing a main part of FIG. 1. 2... High frequency coil, 3... Insulator cylinder, 4...
...heat reflective film, 5 ... cut, 6 ... image pickup tube (electron tube), 7 ... metal parts, 8 ... glass envelope.

Claims (1)

[Claims] 1. An insulating cylinder whose inner surface is coated with a heat reflective film having a cut in a part in the circumferential direction is disposed inside a high-frequency coil, and 1. A method for exhausting an electron tube, comprising arranging an electron tube, heating the coil by passing a high-frequency current through the coil, and simultaneously releasing gas from metal parts of the electron tube and a wall of a glass envelope. 2. The method for exhausting an electron tube according to claim 1, wherein the insulating cylinder is made of glass, and the heat reflecting film is made of Cr or Al.