JPS60146418A - 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 the Invention] The present invention relates to improvements in vacuum valves for vacuum isolation, particularly in low-surge vacuum valves.

[Technical background of the invention and its problems]

In general, vacuum pulp is produced by separating electrodes in a vacuum of 10 Torr or less and utilizing the ambiguous arc-extinguishing and insulating properties of vacuum to interrupt a constant flow. However, because of its excellent arc extinguishing properties, it is 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 used as a military/aircraft valve that does not generate this excessive surge pressure. Its basic configuration is shown in Figure 1.

In FIG. 1, a vacuum pulp 1 has a fixed electrode 5 and a movable electrode 7 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. Fixed support rod 6 and movable support rod 8
Opening and closing operations are performed via a movable support rod 8 supported by an operating mechanism (not shown). 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 each contribute to current interruption with contacts 12 and 13 made of a contact material with a low cutting current, for example, an Ag-No material. Main electrode part 14.1 generally made of pure steel material subjected to degassing treatment
In addition, depending on the current to be cut off, the main electrode part 14.15 may be equipped with a 7mm diameter for magnetic drive or a vertical magnetic field type coil electrode. It consists of a main electrode section that conducts

The biggest problem with the low-surge vacuum pulp constructed in this way is that its breaking performance is only up to about 25 kA. This is because the material has a low breaking current and its breaking performance is worse than the contact material used for general circuit breakers, and even if the contact diameter is increased, the breaking performance does not improve as much as expected. It is.

[Purpose of the invention]

An object of the present invention is to provide a vacuum pulp that has low surges and can be cut by a large current.

[Summary of the Invention] The present invention provides a low-surge vacuum pulp in which the electrode part is made of a low-density new material, and the electrode part is made of a high-current material other than pure steel. It is possible to cut off a large current of about 40 kA, which is about 1.6 times that of the conventional one.

[Embodiments of the invention]

An embodiment of the present invention is shown in FIG.

Figure 2 shows the case where it is applied to the vertical magnetic field system, but it is well known that if a spiral groove is formed on the coil poles in Figure 2 and the four poles, a magnetic drive system will be obtained. This is a common practice.

Further, in FIG. 2, only the electrode portion is shown, but the other portions are substantially the same as in FIG. 1 and are therefore omitted.

In the twenty-first, the fixed/-pole 20 and the movable electrode 21 are each configured as follows. 22, 23
are contacts made of a new material with low thickness, for example, Ag--vC material, and are formed in a convex shape compared to the main electrode and the auxiliary single pole, which will be described later. Also, 24.25 is the main electrode,
Materials for large current shields other than pure copper, such as 0u-Te
alloy, Ou-Bi alloy, Ou-Pb alloy, O
It depends on materials such as u-Or alloys. Reference numerals 26 and 27 are auxiliary electrodes, which are generally made of pure steel. This is a contact point,
It is necessary to use it when the main electrode and coil electrode have poor brazing properties, but when the material is not particularly necessary, the main electrode may also serve as an auxiliary electrode.

28 and 29 are coil electrodes for generating a longitudinal magnetic field, and the number of divisions is appropriately determined in order to sub-adjust the magnetic field strength required for the cutoff current. Reference numerals 30 and 31 are a fixed single-pole support rod and a movable electrode support rod, which necessarily serve as a current path to the outside of the vacuum pulp.

According to the vacuum pulp constructed in this way, firstly, in the case of a small current interruption, the arc should be caused by a material with a low breaking current, and in the case of a small current of 100 Å or less, there will be approximately one vacuum arc spot. Since only a small amount of the new material is generated and the spot itself does not move, the new material is maintained at a relatively low temperature, thereby making it possible to prevent overvoltage from occurring due to cutting.

Next, in the case of large current interruption, the arc is fired at the contact part with the new material, which is also low, but because the current is large, many spots are generated and automatically diffused. At this time, if the main electrodes 24 and 25 are made of pure steel as described above, there is a difference in vapor pressure between them and the contact portions (because of this, the arc is hardly diffused and most of the VC is concentrated in the contact portions). However, pure steel materials also have high vapor pressure, such as 0
By using materials such as u-Bi alloy, Ou-Te alloy, Ou-Pb alloy, Ou-Or alloy, etc., the difference in vapor pressure becomes smaller, so the arc spreads over almost the entire electrode surface. This results in a blocking performance proportional to the electrode diameter.

〔Effect of the invention〕

According to the present invention, the contact portion is formed of a material that produces a low breaking current, and the main electrode portion is formed of a material other than pure copper, such as Ou-T.
e series, Ou-Bi series, Ou7Pb series, Ou-O
A low-surge vacuum pulp having a large current breaking performance of 25 kA or more can be obtained by forming the electrode part from a material suitable for large currents such as r-based alloys.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view showing conventional low-surge vacuum pulp, Figure 2
The figure is a sectional view of a single pole portion showing an embodiment of the present invention. 22.23...Contact points 24, 25...King 1! Goku (7317) Representative Patent Attorney Noriyuki Chika (and 1 others)
Name) Figure 1!

Claims (2)

[Claims] (1) In vacuum pulp, in which at least one pair of electrodes that can be brought into contact with and separated from each other, consisting of a contact and a main electrode with a soldered bolt 9 attached to the center of the contact, is provided in a vacuum container, the contact is connected to a low breaking current. The main electrode part around the main electrode is made of a material having Ou-Te system, Ou-Bi system, Ou-Pb system.
1. A vacuum valve for a vacuum breaker, characterized in that it is made of one type of material selected from On-Or type and On-Or type alloys. (2) The vacuum pulp according to claim 1, wherein the main electrode portion includes a coil electrode for applying an axial magnetic field to the arc.