JPH11134979A - Vacuum bulb and manufacture of vacuum bulb - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate conventional pretreatment process of soldering a terminal part shield with a terminal disk and simplify the assembling work. SOLUTION: In this vacuum bulb having a structure in which a contactor part is surrounded with an approximately cylindrical arc shield, approximately cylindrical end part shields are installed near both ends of the arc shield between the arc shield and an insulating cylinder in the outer circumference of the arc shield, and the inner face of the insulating cylinder is shielded by the end part shields, flange 10a are formed in one end sides of the end parts shields 10A (10B) and the flange 10a are joined to the open end parts of the insulating cylinder 1. The vacuum bulb is manufactured so as to have such a structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum circuit breaker used in a power switchgear, a vacuum switchgear, and the like, and a vacuum valve used as an arc-extinguishing chamber and a method of manufacturing the same.

[0002]

2. Description of the Related Art Generally, vacuum valves are widely used for opening and closing circuits in power switching devices using vacuum circuit breakers, vacuum switches, and the like. FIG. 3 is a longitudinal sectional view showing the configuration of a conventional vacuum valve. In this vacuum valve, an insulating cylinder 1 is constituted by cylinders 1a and 1b made of ceramics and a support fitting 2 joined between the cylinders 1a and 1b. A cylindrical arc shield 3 is held inside the insulating cylinder 1 by an inner peripheral portion of the support fitting 2.

At the open ends of the insulating cylinder 1, end plates 5A and 5B to which end shields 4A and 4B have been brazed in advance by a previous process are aligned with the center of the insulating cylinder 1 accurately. To form a vacuum container. Note that a positioning jig is used for this alignment.

A fixed-side energizing shaft 6A penetrates the center of one end plate 5A, and a contact 7A is provided at the tip of the energizing shaft 6A.
Is installed. The other end plate 5B is provided with a movable-side energizing shaft 6B via a bellows 8 and a guide 9, and a contact 7B is also attached to the end of the energizing shaft 6B.

The bellows 8 is mounted between the movable shaft 6B on the movable side and the end plate 5B so that the shaft 6B can be moved up and down while maintaining the internal vacuum. As a result, the contacts 7A and 7B can contact / separate,
Thus, the power circuit can be opened and closed.

By the way, if the contact 7B is separated from the contact 7A during energization in order to cut off the current, both contacts 7A
An arc is generated between A and 7B. The arc is contact 7A,
7B and charged particles generated by ionization thereof. When they come into contact with the inner surface of the insulating cylinder 1, they cool and solidify there to form a metal film, and the insulating performance of the insulating cylinder 1 is reduced. Is significantly reduced.

Therefore, the above-described arc shield 3 surrounds the entire contacts 7A and 7B so that the metal vapor diffused from the arc does not contact the inner surface of the insulating cylinder 1. Further, the above-described end shields 4A and 4B are provided to shield the vicinity of both open ends of the insulating cylinder 1.

[0008]

As described above, in the conventional vacuum valve and the method of manufacturing the same, components are generally joined together by metal brazing and assembled. Here, the end shields 4A and 4B are previously attached to the end plates 5A and 5A, respectively.
Requires a pre-brazing step to 5B.

When the end plates 5A and 5B are brazed to the open ends of the insulating cylinder 1, brazing is performed in a state where the centers of the end plates 5A and 5B and the center of the insulating cylinder 1 are accurately aligned. Therefore, a positioning jig is required at the time of brazing.

It is desirable that these pre-processes and jigs be omitted as much as possible from the viewpoint of simplifying the assembling work. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vacuum valve and a method of manufacturing the same, which can omit a pre-process of brazing an end shield to an end plate and can simplify an assembling operation. . Another object of the present invention is to
It is an object of the present invention to provide a vacuum valve and a method of manufacturing the same, which can eliminate the need for a positioning jig for brazing the end plate to the opening end of the insulating cylinder and can further simplify the assembling work.

[0011]

According to a first aspect of the present invention, a contact portion is surrounded by a substantially cylindrical arc shield, and the arc shield is insulated from its outer peripheral side near both ends of the arc shield. A substantially cylindrical end shield is attached between the end shield and a vacuum valve having a structure in which the inner surface of the insulating cylinder is shielded by the end shield. A flange is provided at one end of the end shield. It is a vacuum valve joined to the opening end of the insulating cylinder.

According to a second aspect of the present invention, there is provided the vacuum valve according to the first aspect, wherein the outer diameter of the flange has a value between the outer diameter and the inner diameter of the insulating cylinder. A vacuum valve having substantially the same inner diameter as an end portion of the board joined to the insulating cylinder.

Further, the invention corresponding to claim 3 is a method of manufacturing a vacuum valve according to claim 1, wherein a metal film is formed on both open ends of the insulating cylinder;
A heating step of heating in a furnace with a metal brazing between the metal coating formed in the coating forming step and the flange, and after the heating step, the metal brazing is solidified by cooling to form the flange and the insulating cylinder. And a cooling step of joining the opening end of the vacuum valve.

According to a fourth aspect of the present invention, in the method of manufacturing a vacuum valve according to the second aspect, a film forming step of forming a metal film on both open ends of the insulating cylinder;
A heating step of heating in a furnace with a metal brazing between the metal coating formed in the coating forming step and the flange, and after the heating step, the metal brazing is solidified by cooling to form the flange and the insulating cylinder. A cooling step of joining the open end of the end plate, a fitting step of fitting an outer peripheral portion of the flange and an inner surface of an end portion of the end plate joined to the insulating cylinder, and heating and cooling the end plate. A method for manufacturing a vacuum valve, comprising: a brazing step of brazing an inner surface of an end portion and an open end portion of the insulating cylinder. (Operation) Therefore, claims 1 and 3
According to the invention corresponding to the above, by taking the above means, a flange is provided on the end shield and the flange is brazed to the open end of the insulating cylinder, so the conventional end shield is brazed to the end plate. Pre-process can be omitted, and the assembling work can be simplified.

According to a second aspect of the present invention, the position of the end plate is fixed by fitting the inner surface of the end of the end plate to the outer peripheral portion of the flange of the end shield and joining it to the insulating cylinder. Since no misalignment occurs during the brazing step, in addition to the functions corresponding to the first and third aspects, a positioning jig for brazing the end plate to the opening end of the insulating cylinder can be eliminated. Thus, the assembling work can be further simplified.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view showing a configuration of a vacuum valve according to an embodiment of the present invention. FIG. 2 is an enlarged sectional view showing a portion P in FIG.
The same parts as those described above are denoted by the same reference numerals, and detailed description thereof will be omitted. Here, only different parts will be described.

That is, in the present embodiment, a step before brazing the end shield is omitted. Specifically, as shown in FIG. 1 and FIG.
In place of A and 4B, an end shield 10A having a structure in which a flange 10a is bent and expanded in a brim shape and the flange 10a is joined to the metal coating 11 at the open end of the insulating cylinder 1. 10B. 1 and 2
In (a), only one end shield 10A is illustrated in detail, but the other end shield 10B is also
It has the same structure as A. This is shown in FIG.
The same applies to (b) and (c).

Here, the end shields 10A and 10B are
An intermediate portion 10b having an inclined cross section is provided between the flange 10a and the cylindrical portion 10c.
Is not always necessary. For example, the middle part 10
b may have a smooth curved cross section instead of the inclined cross section.

A metal coating 11 is provided on the end of the insulating cylinder 1 made of ceramics at the open end of the insulating cylinder 1 as a metal part.
A and 10B are brazed, and can generally be formed by a so-called telefunken method of firing an oxide of Mo and Mn. In addition to the telefunken method, a forming method by surface diffusion of an active metal such as Ti or Zr or a forming method by vapor deposition of a metal vapor in a vacuum can be used. In any case, it is only necessary that a metal component can be joined to the ceramic insulating cylinder 1 by brazing.

With the above-described structure of the vacuum valve, in the manufacturing method, the metal coating 1
1 and a flange 10a of the end shields 10A and 10B, a metal brazing material (generally, a silver-copper alloy) is sandwiched and heated in a furnace. Thereby, the brazing metal is melted at a high temperature. Subsequently, when the metal brazing solidifies by cooling, the end shields 10A and 10B are firmly joined to the metal coating 11 at the opening end of the insulating cylinder 1.

As described above, in the vacuum valve and the method of manufacturing the same according to the present embodiment, the flanges 10a of the end shields 10A and 10B are joined to both open end portions of the insulating cylinder 1, so that the end portions are different from the prior art. A pre-process of brazing the shield to the end plate can be eliminated. (Modification) Next, a modification of the present embodiment will be described. That is, as shown in FIGS. 2B and 2C, the outer diameter of the flange 10a of the end shields 10A and 10B is set to an intermediate value between the inner diameter and the outer diameter of the insulating cylinder 1 and the end plate 5A,
The outer circumference of the flange 10a and the end plates 5A and 5B are made substantially the same as the inner diameter of the end joined to the insulating cylinder 1 of 5B.
A structure may be adopted in which the inner surface of the end portion of the portion joined to the insulating cylinder 1 is fitted. In addition, the end plate 5A shown in FIG.
5B is the same as the conventional one, and the end plates 5A and 5B shown in FIG. 2 (c) have a flange having an outer diameter substantially the same as the outer diameter of the insulating cylinder 1.

According to such a fitting structure, the end plate 5A,
5B is fixed to the flanges 10a of the end shields 10A and 10B and does not shift left and right. Therefore, a brazing step of brazing the ends of the end plates 5A and 5B and the opening end of the insulating cylinder 1 by heating and cooling. At this time, unlike the related art, a positioning jig for fixing so as not to shift can be unnecessary.

As described above, according to the present embodiment, the flanges 10a are provided on the end shields 10A and 10B, and the flange 10a is brazed to the open end of the insulating cylinder 1. The pre-process of brazing to the board can be omitted, and the assembling work can be simplified.

The end plates 5A, 5B are joined to the insulating cylinder 1 by fitting the inner surfaces of the ends of the end plates 5A, 5B to the outer peripheral portions of the flanges 10a of the end shields 20A, 20B. , 5B are fixed, and no misalignment occurs during the brazing process, so that a positioning jig for brazing the end plates 5A, 5B to the open end of the insulating cylinder 1 can be dispensed with. Further, the assembling work can be simplified. In addition, the present invention can be implemented with various modifications without departing from the scope of the invention.

[0025]

As described above, according to the present invention, it is possible to provide a vacuum valve and a method for manufacturing the same, which can omit a pre-process for brazing an end shield to an end plate and can simplify an assembling operation. Also, a positioning jig for brazing the end plate to the opening end of the insulating cylinder can be dispensed with.
Assembly work can be simplified.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a configuration of a vacuum valve according to an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view showing a part of the vacuum valve according to the embodiment and its modification;

FIG. 3 is a longitudinal sectional view showing a configuration of a conventional vacuum valve.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Insulating cylinder 1a, 1b ... Cylinder 2 ... Supporting metal 3 ... Arc shield 5A, 5B ... End plate 7A, 7B ... Contact 8 ... Bellows 9 ... Guide 10A, 10B ... End shield 10a ... Flange 10b ... Middle part 10c ... Cylindrical part 11 ... Metal coating

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Kiyoshi Nanbu 1 Toshiba-cho, Fuchu-shi, Tokyo Toshiba Corporation Fuchu Plant

Claims (4)

[Claims] A contact portion is surrounded by a substantially cylindrical arc shield, and a substantially cylindrical end shield is provided between the arc shield and an insulating tube on the outer periphery thereof near both ends of the arc shield. A vacuum valve having a structure in which an inner surface of the insulating cylinder is shielded by the end shield, wherein a flange is provided at one end of the end shield, and the flange is joined to an open end of the insulating cylinder. Features vacuum valve. 2. The vacuum valve according to claim 1, wherein an outer diameter of the flange has a value between an outer diameter and an inner diameter of the insulating cylinder, and an end portion of an end plate joined to the insulating cylinder. A vacuum valve having substantially the same inner diameter as that of the vacuum valve. 3. The method of manufacturing a vacuum valve according to claim 1, wherein a metal film is formed on both open ends of the insulating cylinder, and the metal film and the flange are formed by the film forming step. A heating step of heating in a furnace with a metal brazing in between, and after the heating step, includes a cooling step of solidifying the metal brazing by cooling to join the flange and the opening end of the insulating cylinder. A method of manufacturing a vacuum valve. 4. The method for manufacturing a vacuum valve according to claim 2, wherein a metal film is formed on both open ends of the insulating cylinder, and the metal film and the flange are formed by the film forming step. A heating step of heating in a furnace with a metal brazing in between, and after the heating step, a cooling step of solidifying the metal brazing by cooling to join the flange and the opening end of the insulating cylinder; A fitting step of fitting an outer peripheral portion of the flange to an inner surface of an end portion of the end plate which is joined to the insulating cylinder; and heating and cooling the end portion of the end plate and the opening end portion of the insulating cylinder. And a brazing step for brazing.