JPS6171519A - Vacuum bulb - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Technical field of invention] The present invention relates to an improved vacuum valve 1ζ.

[Technical background of the invention and its problems]

A typical vacuum valve opens electrodes in a high vacuum of 10"" or less and cuts off current by utilizing the excellent arc-extinguishing and insulating properties of vacuum. However, because of its excellent arc-extinguishing properties, it is also widely known that when a small current is interrupted, an excessive surge voltage is generated due to a so-called new phenomenon. A low-surge vacuum valve is a vacuum valve that does not generate this excessive surge voltage. Its basic configuration is shown in Figure 1.

In FIG. 3, a vacuum valve 1 has a fixed electrode 5 and a movable electrode 7 mounted on fixed support rods in an airtight container 2 whose openings at both ends are sealed to a vacuum of 10 Torr or less by a fixed end plate 3 and a movable end plate 4, respectively. 6 and a movable support rod 8, and an operating mechanism (not shown) performs opening and closing operations via the movable support rod 8. 9 is a bellows, 10 is a bellows cover, and 11 is a shield.

The fixed side electrode 5 and the movable side electrode 7 are made of contact materials 12 and 13 made of a contact material with low breaking current, for example, Ag-WC material, and pure steel material subjected to a degassing treatment that contributes to cutting off flow. It is composed of main electrode parts 14 and 15. In addition, in order to improve the breaking performance as a vacuum valve, the main electrode parts 14 and 15 are provided with so-called spiral grooves 16 for magnetically driving the vacuum arc that has moved to the polarization part to prevent local stagnation of the arc. , to improve cutting performance.

Regarding the low surge vacuum valve 1 configured in this way,
When cutting off a small current, the arc is fixed only to the contacts. Although its low surge properties are not impaired, when a large current is cut off, the arc spreads poorly due to the difference in arc voltage between the low surge contact material and the electrode material.
The actual situation is that the arc spreads poorly to 5, and as a result, it is only possible to provide a breaking performance that is proportional to the diameter of the low-surge contact.

Another method is to configure the main electrodes 14 and 15 with the same material as the low-surge contact material, but although this improves the arc spread, it requires the use of a large amount of very expensive low-surge contact material. This makes vacuum pulp expensive.

[Purpose of the invention]

An object of the present invention is to provide a vacuum pulp that has low surge and is capable of interrupting large currents.

[Summary of the Invention] The present invention provides a low-surge vacuum pulp 1 in which the electrode part is made of a new low-temperature material and the electrode part is made of a material having arc voltage characteristics comparable to those of the contact part. This enables a larger current to be cut off than before.

Examples of the invention] An embodiment of the present invention will be described with reference to the drawings.

In FIG. 1, only the electrode portion is shown, but other parts are omitted because they are the same in function and configuration as in FIG. 3. Further, FIG. 1 shows a cross-sectional view of the electrode portion of the vacuum pulp, while FIG. 2 shows a plan view as viewed from the contact side.

In the drawings, the fixed side electrode 20 and the movable side electrode 21 are each configured as follows. 24 and 25 are contacts made of a material having low breaking current characteristics, for example, Ag-WC material. Further, 26.27 is a main electrode, which is made of a material having arc voltage characteristics similar to the material having low cutting properties, such as a Cu-Cr alloy or a Cu-Bi alloy.
Made of materials such as alloys. Further, the main electrodes 26 and 27 are suitably provided with a plurality of so-called spiral grooves for magnetically driving the generated vacuum arc so as to form pairs on the fixed and movable side electrodes. 22 and 23 are a fixed support rod and a movable support rod, which serve as a current path to the outside of the vacuum valve.0 According to the vacuum pulp configured in this way, first of all, in the case of a small current interruption, a material having a low interruption current is used. In the case of a small current of 100 A or less, only one vacuum arc spot is generated and the spot itself does not move (this is why the new material with a low vacuum arc is maintained). Therefore, generation of overvoltage due to cutting can be prevented.

In the case of a large magnetic current interruption, an arc fired in a material with a low cutting current will produce a large number of spots due to the large current and will be automatically spread out. At this time, Lord'&! pole 2
Since the contacts 6 and 27 are made of a material having the same arc voltage as the contacts 24 and 25, the contacts 24 and 25
The arc no longer sticks to the electric current and is diffused to the electric current '&2627. The arc that has moved to the electrodes 26 + 27 continues to move outward from the electrodes due to the action of the spiral groove provided there, and finally rotates at the end of the electrode due to the magnetic driving force, so that no local stagnation occurs. [Effects of the Invention] According to the present invention, the contact portion is made of a material having a low breaking current, such as λg-WC, and the main electrode portion forms the contact point.

1. To obtain a low-surge vacuum pulp with large current interrupting properties by forming a new material with a low arc voltage and a material having an arc voltage characteristic of about 1, such as a Cu-Cr-based or CU-Bi-based material. I can do it.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an electrode portion showing an embodiment of the present invention, FIG. 2 is a plan view of the electrode, and FIG. 3 is a sectional view of a conventional vacuum pulp. 24.25...Contact 26.27...Main electrode (7317) Agent Patent attorney Noriyuki Chika
(1 other person) Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] In a vacuum valve having a pair of spiral electrodes that are provided in a vacuum container so as to be able to freely come into contact with and separate from them, the material of the contacts of the electrodes is Ag-WC, and the material of the electrodes is Cu-Cr or Cu-B.
A vacuum valve characterized by using i.