JPH0211966B2 - - Google Patents

Description

[Detailed Description of the Invention] A. Industrial Application Field The present invention relates to a vacuum interrupter and a method for manufacturing the same, and particularly relates to a vacuum interrupter in which a vacuum vessel is formed by joining ceramics and a copper alloy member without using a brazing material. Concerning an interrupter and its manufacturing method.

B. Summary of the Invention The first invention is a vacuum interrupter in which a pair of electrodes are disposed facing each other in a vacuum container so as to be able to move toward and away from the vacuum container. By combining the members and forming a hermetic joint, the members constituting the vacuum container can be hermetically joined without using a brazing material.

Further, a second invention is a method for manufacturing a vacuum interrupter according to the first invention, which includes forming a metallized layer by heating a ceramic member and a copper member containing 0.1 to 0.6% by weight of chromium and airtightly joining them together. , does not require sintering, does not use brazing metal, is low cost, has a small number of steps,
This makes it possible to easily manufacture a vacuum interrupter.

C. Prior Art In general, a vacuum interrupter has an insulating tube 1 made of an insulating material such as ceramics, as shown in FIG.
Fe-Ni alloy with both openings fixed to this end,
A vacuum container 4 is formed by airtightly closing a metal end plate 3 made of stainless steel through a sealing fitting 2 made of Fe-Ni-Co alloy (Kovar) or the like.
A pair of electrodes 5 are introduced from the center of each metal end plate 3 into the vacuum vessel 4 through a pair of electrode rods 6, which are arranged so as to be relatively approachable and detachable while maintaining the airtightness of the vacuum vessel 4. (Contact/separation) It is configured to be freely provided.

In FIG. 2, 7 is a metal bellows that prevents the movable electrode rod 6 from impairing the airtightness of the vacuum container 4, 8 is a cylindrical shield that concentrically surrounds the pair of electrodes 5, etc. The intermediate portion of the insulating cylinder 1 is supported via a ring-disc-shaped support fitting 9 installed on the inner wall surface of the insulating cylinder 1.

D Problems to be Solved by the Invention However, in the above-mentioned general vacuum interrupter, since the insulating tube 1, which together with the metal end plate 3 forms the vacuum container 4, is made of an insulator such as ceramics, For bonding, it is necessary to use a sealing fitting 2 made of a ferromagnetic material such as Kovar, which has a coefficient of thermal expansion similar to that of ceramics, etc., which may cause noise due to magnetostrictive vibration of the sealing fitting 2 when a large current is applied. The temperature rises due to the eddy current caused by the induced magnetic field, and the joint part of the insulating cylinder 1 is metalized to prevent it from joining with the sealing fitting 2 by brazing.
In addition, the surface of the metallized layer must be subjected to nickel plating, sintering, etc. to improve wettability with the brazing material, and is also used for joining the insulating tube 1 and the metal end plate 3 to the sealing fitting 2. There are problems such as limited brazing filler metal.

In order to deal with this problem, a vacuum interrupter has been devised in which a vacuum vessel is formed by brazing metal end plates made of copper to both ends of an insulating cylinder, but in such a vacuum interrupter, the metal end plates are made of copper. Therefore, there is no need for sealing fittings, and since copper is non-magnetic, it does not generate heat due to magnetostrictive vibrations or induced magnetic fields during energization, and the application range of brazing filler metal can be expanded. A metallized layer mainly composed of molybdenum, tungsten, etc. is formed at the joint of the metallized layer, and the surface of the metallized layer is subjected to nickel plating and sintering, and a brazing material is used to join the insulating cylinder and the metal end plate. There are problems such as having to do this.

E. Means for Solving the Problems In order to solve these conventional problems, the first invention provides a cylindrical body made of an insulating material or a metal and having at least one end open, and an end plate made of a metal or an insulating material. In a vacuum interrupter, a pair of electrodes are disposed facing each other so as to be able to come into contact with and separate from the vacuum container. This is what I did.

Further, in a second invention, when manufacturing the vacuum interrupter of the first invention, a ceramic member and a copper member are hermetically bonded together by heating.

F Effect According to the vacuum interrupter and its manufacturing method as described above, the ceramic member and 0.1 to 0.6% by weight
Chromium-containing copper members can be bonded with excellent airtightness and strength.

G Example Hereinafter, the present invention will be explained in detail based on an example shown in FIG.

The vacuum interrupter according to the present invention includes, for example, a first
Alumina formed into a cylindrical shape, as shown in the figure,
End plates 11 formed into a disk shape and made of copper containing 0.1 to 0.6% by weight of chromium are hermetically bonded to both ends of an insulating tube (cylindrical body) 10 made of ceramics such as mullite, zircon, steatite, etc. At the same time, the inside is evacuated to a high vacuum of 13.33 mPa (10 ^-4 Torr) or less to form a vacuum container 13, and in this vacuum container 13, a
A pair of electrodes 14 are introduced from the center of each end plate 11 so as to be able to approach and separate from each other through a pair of electrode rods 15 which are introduced so as to be able to approach and separate from each other while maintaining the airtightness of the vacuum vessel 13. It is configured.

In addition, in FIG. 1, 16 is a metal bellows;
Reference numeral 7 denotes a cylindrical shield that concentrically surrounds the pair of electrodes 14, etc., and its intermediate portion is supported by a ring-disc-shaped support fitting 18 implanted on the inner wall surface of the insulating cylinder 10. be.

In order to manufacture the vacuum interrupter of the first invention described above, first, the insulating cylinder 1 with the shield 17 attached thereto is
As shown in FIG. 1, the end plates 11 with electrodes 14, 14, electrode rods 15, etc. attached are attached to both ends of the vacuum interrupter, and the vacuum interrupter is temporarily assembled.
Store in a vacuum atmosphere of 13.33mPa (10 ^-4 Torr) or less or in a gas atmosphere such as helium or hydrogen that does not oxidize copper. Next, the temporarily assembled vacuum interrupter is continuously heated at a temperature of 900° C. or higher for 10 minutes or more in these atmospheres to airtightly bond the insulating cylinder 10 and each end plate 11, and then slowly cooled in these atmospheres. The desired vacuum interrupter is completed by reducing the residual stress in each end plate 11 through its plastic deformation. In addition, when manufacturing in a gas atmosphere such as helium or hydrogen,
A step is added in which the inside of the vacuum vessel 13 is heated and exhausted through an exhaust pipe or an exhaust hole provided in either the electrode rods 15, 15 or the end plates 11, 11.

In the vacuum interrupter of the above embodiment, a vacuum is generated by an insulating tube 10 made of ceramics and an end plate 11 made of copper containing 0.1 to 9.6% by weight of chromium, which airtightly closes both open ends of the insulating tube 10. Although the case of forming the container 13 has been described, the formation of the vacuum container is not limited to this. For example, a metal tube (cylindrical body) made of copper containing 0.1 to 0.6% by weight of chromium and this metal tube A vacuum container may be formed by an end plate made of ceramic such as alumina or mullite that airtightly closes both open ends of the container, or a cylindrical cup with a bottom made of copper containing 0.1 to 0.6% by weight of chromium may be formed. A vacuum container may be formed by a metal case (cylindrical body) of a shape) and an end plate made of ceramics such as alumina that airtightly closes the open end of the metal case. It is not limited to the case where it is formed from a single insulating cylinder 10 made of ceramics, but it is also made of ceramics joined in series through a thin annular sealing fitting (copper member) made of copper containing 0.1 to 0.6% by weight of chromium. A single insulating cylinder may be formed by two or more insulating cylinders (ceramic members), or a cylindrical copper member containing 0.1 to 0.6% by weight of chromium may be connected in series at both ends of a cylindrical ceramic member. A vacuum vessel is formed by airtightly joining them to form a single cylindrical body, or by hermetically closing both ends of a cylindrical ceramic member with a bottomed cylindrical copper member containing 0.1 to 0.6% by weight of chromium. It is of course possible to produce the same vacuum containers as those of the above-mentioned embodiments, and to manufacture each of these vacuum containers by the above-mentioned methods.

H. Effects of the invention As described above, the first invention provides a
In a vacuum interrupter in which a pair of electrodes are arranged facing each other so as to be able to freely come and go, the vacuum vessel is formed by combining a ceramic member and a copper member containing 0.1 to 0.6% by weight of chromium and airtightly bonding the same. To make it possible to join both members with excellent airtightness and strength, to eliminate the need to use a brazing material unlike conventional ones, and to make a vacuum interrupter excellent in airtightness and impact resistance. and can be made inexpensive.

Further, the first invention of the method for manufacturing a vacuum interrupter is to form a vacuum container by heating and airtightly bonding a ceramic member and a copper member containing 0.1 to 0.6% by weight of chromium. Unlike conventional methods, there is no need to form a metallized layer using expensive molybdenum or the like on the joint surfaces of ceramic members, and sintering, and there is no need to use a brazing filler metal, resulting in a significant reduction in manufacturing costs. In addition to being able to
This has the effect of reducing the number of steps and facilitating manufacturing.

[Brief explanation of drawings]

FIG. 1 is a half-cut vertical cross-sectional view of a vacuum interrupter according to the present invention, and FIG. 2 is a vertical cross-sectional view of a general vacuum interrupter. 10... Insulating cylinder (cylindrical body), 11... End plate, 1
1... End plate, 13... Vacuum container, 14... Electrode.

Claims (1)

[Scope of Claims] 1. A vacuum interrupter in which a pair of electrodes are disposed facing each other in a vacuum container so as to be able to move toward and away from the vacuum container. In addition to combining
A vacuum interrupter characterized by being formed in an airtight manner. 2. A method for manufacturing a vacuum interrupter, which comprises forming a vacuum container by heating and airtightly joining a ceramic member and a copper member containing 0.1 to 0.6% by weight of chromium. 3. A vacuum container made by temporarily assembling a ceramic member and a copper member containing 0.1 to 0.6% by weight of chromium,
Claim 2, characterized in that the product is placed in a vacuum atmosphere, continuously heated at a temperature of 900°C or more for 10 minutes or more to form an integral airtight seal, and then slowly cooled in the same atmosphere. A method of manufacturing the vacuum interrupter described. 4. A vacuum container in which a ceramic member and a copper member containing 0.1 to 0.6% by weight of chromium are temporarily assembled is placed in a gas atmosphere that does not oxidize copper, and heated continuously for at least 10 minutes at a temperature of 900°C or higher. 3. The method of manufacturing a vacuum interrupter according to claim 2, wherein the vacuum interrupter is integrally hermetically sealed and then slowly cooled in the same atmosphere.