JPH03283336A - Discharge tube - Google Patents

Abstract

PURPOSE:To obtain a discharge tube whose discharge characteristics are stable over a long period and whose interelectrode electrostatic capacity is small by using a porous ceramics coated with glass to form a sealed container. CONSTITUTION:A porous ceramics coated with glass 13a is used to form a sealed container 13 provided in such a manner as enclosing two main electrodes 11, 12 disposed opposite to each other; i.e., the electrodes 11, 12 are heated and sealed to both cut pipe surfaces of the tubular sealed container 13 by a sealing material 15 of gold or silver solder, etc., whose melting point is lower than that of the ceramics, the tubular 13 being made of the porous ceramics of a low dielectric constant and coated with glass whose coefficient of thermal expansion is near to that of the electrodes 11, 12. Airtightness of the sealed container is thereby held high and also the interelectrode electrostatic capacity of a discharge tube is made smaller.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a high-voltage discharge tube of a high-pressure enclosed type, and particularly to a discharge tube in which the electrostatic container between both electrodes is lowered.

[Conventional technology]

Conventionally, in this type of discharge tube, as shown in FIG. 3, a pair of opposing electrodes 101 and 102 are sealed to a closed container 103 made of ceramic material via a sealing material 105 made of silver brazing material. . In the internal space of the sealed container 103, an adhesive 10 is applied to the electrode 101 so as to give the discharge tube certain discharge characteristics.
A high-pressure inert dregs 104 is enclosed through an enclosure tube 101a that is airtightly added by 1b.

[Problem to be solved by the invention]

However, in the above-mentioned conventional high-pressure sealed discharge tube, in order to maintain a high degree of airtightness, a highly dense ceramic material is used for the sealed container, or the sealed container itself is made thick. However, since the dense ceramic has a high dielectric constant, there is a drawback that the electrode capacitance of the discharge tube becomes high.

[Means to solve the problem]

The present invention includes two main electrodes arranged opposite to each other,
A discharge tube comprising a closed container provided to contain these two main electrodes is characterized in that the closed container is made of a porous ceramic material coated with glass.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a longitudinal sectional view of one embodiment of the present invention.

The electrodes 11 and 12 are made of a porous ceramic material with a low dielectric constant coated with a glass coating 13a having a coefficient of thermal expansion similar to that of the electrodes. Alternatively, it is heat-sealed with a sealing material 15 made of silver solder. On the outside of the electrode 11,
A sealing tube 11a for feeding high-pressure inert gas 14 into the space inside the discharge tube is airtightly attached with an adhesive 11b, and after feeding the high-pressure inert gas 14, the sealing part 11
The opening is hermetically sealed at c. In addition, the airtight container 130
Glass coating is not necessary on both cut tube surfaces, and it is sufficient to apply glass coating before cutting the long ceramic tube.

FIG. 2 shows a longitudinal sectional view of another embodiment of the invention.

The flat parts of the inner surfaces of the electrodes 21 and 22, excluding the discharge protrusions 26 and 27, are covered with a sealing material 25 made of a glass material with a thermal expansion coefficient equivalent to that of gold soldering and silver soldering. An insulating surface is created following the insulating surface of the container 13 to form an electrode 21.2.
The insulation distance between the two electrodes has been extended to increase the dielectric strength voltage between the electrodes.

In the above example, a sealed container made of glass-coated low-density (porous) ceramic with a low dielectric constant is used, so it has the same thickness as a high-density material but has low leakage and low interelectrode capacitance. It was realized.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to obtain a discharge tube whose discharge characteristics are stable over a long period of time and whose interelectrode capacitance is small.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of one embodiment of the present invention, FIG. 2 is a longitudinal sectional view of another embodiment of the invention, and FIG. 3 is a longitudinal sectional view of a conventional discharge tube. 11, 12.21.22・=electrode, lla, 12a・・
... Enclosure tube, llb, 21. b...Adhesive material, 11c. 21c...Sealing part, 13.23...Airtight container, 13a, 23a...Glass coating, z. 24...High pressure inert gas, 15.25...
... Seal kidnapping.

Claims (2)

[Claims] (1) In a discharge tube consisting of two main electrodes arranged facing each other and a sealed container provided to contain these two main electrodes, the sealed container is made of a porous ceramic material coated with glass. A discharge tube characterized in that it is used. (2) The discharge tube according to claim 1, wherein the two main electrodes are covered with a glass material on an inner surface of the sealed container except for a discharge portion.