JPH0619938B2 - Vacuum switch - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum switchgear, and more particularly to a structure for improving the breaking performance.

[Conventional technology]

FIG. 8 is a perspective view showing an electrode of a conventional vacuum switchgear disclosed in, for example, Japanese Patent Laid-Open No. 61-245428, in which (4) is a main electrode and (10) is a magnetic field. Therefore, the coil electrode is provided so as to surround the outer periphery of the main electrode (4). This electrode is divided into, for example, four parts. The material of the coil electrode (10) is conventionally composed of a material having the same resistance value as or lower than the material of the main electrode (4), and in this case, the main electrode (4) and the coil electrode (10). Is made of copper. Although not shown, a pair of electrodes consisting of the main electrode (4) and the coil electrode (10) shown in FIG. There is. The coil electrode (10) has a facing surface at the same level as the facing surface of the other main electrode of the main electrode (4).

Next, the operation will be described. An arc is generated between the main electrodes (4) when the pair of main electrodes (4) facing each other and freely separated from each other are opened. This arc becomes a stable arc due to the axial magnetic field generated by the coil electrode (10).

[Problems to be solved by the invention]

The conventional vacuum switchgear is configured as described above, and since the coil electrode (10) is made of a material having the same resistance value as or lower than that of the main electrode (4), the main electrode (4) is opened. Occasionally generated arc is transferred to the coil electrode (10), which prevents the partial melting of the coil electrode (10) and the generation of an axial magnetic field for forming a stable arc, which deteriorates the cutting performance. There was a problem.

The present invention has been made to solve the above problems, while preventing the transfer of the arc to the coil electrode (10), it is possible to generate a stable magnetic field in the axial direction, the cutting performance of An object is to obtain a vacuum switchgear that can be improved.

[Means for solving problems]

In the vacuum switchgear according to the present invention, the coil electrode surface corresponding to the facing surface side of the pair of main electrodes facing each other is formed of a high resistance material having a resistance value higher than that of the material forming the main electrodes.

[Action]

Since the opposing surface side of the coil electrode in the present invention is formed of a high resistance material having a resistance value higher than that of the material forming the main electrode, the transfer of the arc to the coil electrode is prevented and a stable axial magnetic field is formed. Can be generated and the cutoff performance is improved.

〔Example〕

An embodiment of the present invention will be described below. In FIG. 1, (15) is a material forming the facing surface of the coil electrode (10), which has a higher resistance than the material forming the main electrode (4) and the coil electrode (10) other than the facing surface. It is the body. In this embodiment, the main electrode (4) and the coil electrode (10) are formed of copper, and the coil electrode (10) on the facing surface side is covered with SUS. Note that other configurations are the same as or equivalent to those of the conventional one shown in FIG.

An arc is generated between the main electrodes (4) when the pair of main electrodes (4) facing each other and freely separated from each other are opened. Coil electrode
Since the high resistance body (15) forming the facing surface of (10) has a higher resistance value than the material forming the main electrode (4) and the coil electrode (10) other than the facing surface, the high resistance body (15) is formed between the main electrodes (4). The generated arc can be prevented from transferring to the coil electrode (10), the arc can be prevented from being generated in the coil electrode (10), and a stable axial magnetic field can be generated to form a stable arc. . Therefore, damage to the coil electrode (10) can be reduced, and the cutoff performance can be improved. FIG. 2 (a) is a plan view showing the facing surface of the electrode according to this embodiment, and FIG.
8E are plan views showing facing surfaces of electrodes according to other embodiments. In the embodiment shown in FIG. 2 (b), the main electrode (4)
There are four grooves (18) in the. In the figure, (101), (102), (10
3) and (104) represent coil electrodes, respectively. Groove on main electrode (4)
By providing (18), the following effect can be obtained in addition to the effect of the above embodiment. As shown in Fig. 2 (a), when an arc is generated at the point (Q), if there is no groove (18), the coil electrode (10
A lot of current flows in 1). Therefore, the magnetic flux may be unevenly distributed and unevenly distributed, and the arc may concentrate. But,
If the groove (18) is provided as shown in Fig. 2 (b), the current will flow to the main electrode (4).
It is distributed to each coil electrode (101)-(104) through the vicinity of the center of. Therefore, it is possible to prevent uneven magnetic flux due to uneven distribution of current. In addition, the provision of the groove (18) has an effect of reducing eddy current.

As yet another embodiment, as shown in FIG. 2 (c), the groove
(18) may be provided more than the number of coil electrodes (101) to (104). In this case, it is possible to further homogenize the magnetic flux and reduce the eddy current. Further, the groove (18) is shown in FIG. 2 (d) and FIG. 2 (e).
It can also be provided in a shape such as. In the above embodiment, the coil electrode (10) is divided into four parts, but it may be divided into any number. Further, although the opposing surface of the coil electrode (10) is formed by being covered with SUS, the present invention is not limited to this, and copper and SUS may be preliminarily bonded and integrally formed.
In addition, the main electrode side of the coil electrode (10) and the outside of the coil electrode, etc.
It may be formed by covering with SUS, and the entire coil electrode (10) is made of SUS.
You may form with. Further, the high resistance body (15) is not limited to SUS, and any material having a resistance value higher than that of the material forming the main electrode (4) may be used. Furthermore, for example, it may be formed of an insulating material having no conductivity such as ceramics. In this case, since it does not conduct electricity at all, the arc does not transfer to the coil electrode (10), which is more effective. large.

〔The invention's effect〕

As described above, according to the present invention, since the coil electrode surfaces corresponding to the pair of main electrode surface sides facing each other are made of a material having a higher resistance value than the material forming the main electrodes, There is an effect that a vacuum switchgear can be obtained which can prevent the transfer of an arc, generate a stable axial magnetic field, and improve the breaking performance.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an electrode relating to a vacuum switchgear according to an embodiment of the present invention, and FIG. 2 (a).
1 is a plan view of the electrode shown in FIG. 1, FIGS. 2 (b) to 2 (e) are plan views showing electrodes of another embodiment of the present invention, and FIG. 3 is a view showing electrodes of a conventional vacuum switchgear. It is a perspective view shown. In the figure, (4) is the main electrode, (10), (101), (102), (103), (1
04) is a coil electrode, and (15) is a high resistance material having a higher resistance value than the material forming the main electrode. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (3)

[Claims] 1. A pair of main electrodes provided in a vacuum chamber so as to face each other so as to be able to come into contact with and separate from each other, and at least one of the main electrodes encloses an outer periphery of the main electrode and has a facing surface. In a vacuum switchgear including a coil electrode having opposing surfaces of the same level, the opposing surface side of the coil electrode is formed of a high resistance material having a resistance value higher than that of the material forming the main electrode. Switchgear. 2. The vacuum switchgear according to claim 1, wherein the main electrode is provided with at least one groove from the outer end toward the inner side. 3. The vacuum switchgear according to claim 1 or 2, wherein the high resistance material having a resistance value higher than that of the material forming the main electrode is an insulator.