JPS60136118A - Method of producing 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 a method for producing vacuum pulp, and particularly to improvements in a method for producing contacts thereof.

[Technical R# of the invention: and its problems] As is well known, the vacuum pulp contacts for heavy soil use are made from contact materials mainly composed of copper (Cu) and chromium (Or). It is formed. This type of contact is characterized by copper (Cu)
) The dihedral solubility is almost zero and there is little release of heat, and the steel (
Cu) j Superior adhesion resistance (= excellent chromium (Cu
) and 4I barrier properties (2) by distributing unreliable steel (Cu) (2) by exhibiting excellent cold resistance, droop pressure resistance, and breaking properties.

By the way, the vacuum breaker is small size 4! I! The scope of application has been rapidly expanding due to its superior features compared to other types of circuit breakers, such as electrical, maintenance-free, and environmentally controlled circuit breakers. Larger flow (e.g. 40-60 KA) from 1 gl tract below
The range of application has been expanded from circuits with a voltage of 36 KV or less to circuits with a high voltage (for example, 72 KV or more).

ff- as vacuum breakers become more popular and become more popular.
Therefore, there has been a demand for improved contact quality.

The unreliable welding resistance and magnetic pressure properties are achieved by making the vacuum valve more compact through the miniaturization of the contacts, and further by making the entire vacuum breaker smaller (2) This contributes to the expansion of the applicable range of C1. This can be said to be a necessary characteristic.However, the voltage resistance of a contact depends on the melting point and hardness of the alloy of the contact material.

Vapor pressure, filtering of components to prevent the melt layer, and their distribution form play a major role.

On the other hand, copper (Cu)-chromium (Cr) system contacts are made of tungsten (W) (melting point 3380 C, boiling point 6000 C).
C) - Chromium (Or) (melting point 1
875℃, boiling point 2430G) as a soil component, 42, arc heat (heat released from a high melting point metal at a higher temperature than 2). It is comparatively low, and has the characteristic that the same area inhibition of the dielectric strength after the magnetic current generated by the discharge of the hot abrasive disappears is reduced.

However, chromium (Cr) is a metal that is extremely easily oxidized. In addition, the formed oxide is extremely difficult to dissociate in hydrogen or vacuum, so during the manufacturing process of the vacuum valve, which is the final vacuum seal after the contact is manufactured, the contact surface is exposed to atmospheric moisture, oxygen, etc. easily contaminated by gases, etc. However, if the contact surface becomes contaminated, it will have a negative effect on the vacuum valve's shutoff performance and voltage resistance, so the contacts must be handled with extreme care before vacuum sealing. This has been a major problem in vacuum pulp production.

In addition, as a means to improve the welding resistance of copper (Cu)-chromium (Or) based contacts, the surface f of the contact is partially melted and cooled with a high energy density heat source (Japanese Patent Laid-Open No. 57-50
No. 2144) has been proposed. However, this no
However, if you don't choose the right timing for melting and cooling,
The surface of the contact after melting and cooling is already contaminated with the seal, reducing the shutoff performance and m4 resistance of the vacuum valve.

Therefore, when manufacturing a vacuum valve with steel (Cu)-chromium (Cr) system contacts, the characteristics of the contacts will not deteriorate during the period from the manufacture of the contacts to the final sealing C2. A manufacturing method is required.

[Purpose of the invention]

The present invention was made in the light of the above-mentioned circumstances, and is based on copper (C
u) - Method for manufacturing a vacuum valve equipped with chromium (Cr)-based contacts (Secondly, providing a method for manufacturing a vacuum valve that does not cause contamination on the contact surface and has improved shrinkage and welding resistance) The purpose is to

[Summary of the invention]

The present invention provides a method for manufacturing a vacuum valve in which a through shaft with solidified contacts is attached to two end plates 6, and the end plates are sealed with an insulating valley. ) Copper (Cu) or chromium (Cr) of 100 μm or less is adhered to the surface of the sintered body by C-neer rtfz or more so that the final thorny surface layer is copper (eu). This is followed by heating and alloying with a heat source with high energy density (secondarily, this is a method for manufacturing vacuum valves that causes less contamination of the contact surface and does not reduce the shutoff performance or welding resistance.

[Embodiments of the invention]

Is the following an implementation of the present invention? IIt-Drawings (explained using two).

First, the overall structure of the related vacuum valve according to the present invention will be explained in the first place.
An explanation will be given with reference to the drawings. The vacuum container 1 includes an insulating container 2 made of an alumina porcelain material, and an iron (Fa)-=Ni-cobalt (Co) system or a thermal expansion coefficient similar to that of the insulating container 2 at both ends of the insulating container 42. Fairy (Fe)
)-end plate 3a formed from a nickel (Ni) alloy
and 3b, and the internal pressure is 10-' Tor
The vacuum is greater than r. The inside g of this vacuum container 1
(= represents a pair of magnetic poles 4a that can be freely approached and separated and equipped with contacts.
, 4b are provided. A fixed threaded shaft 5a made of, for example, oxygen-free steel is attached to one side 4a of this magnetic pole, and the end plate 3a is passed through the air □ secret ship = Teida and guided out.
, the other 4bl2 is similarly attached with an aT moving turtle shaft 5b made of oxygen-free steel, and the end plate 3bl is attached via a bellows 6 made of stainless steel material, for example, and the reef 4a and 4b can be freely moved in and out of contact. An arc shield 7 is provided to surround the magnetic poles 4a and 4b, and prevents metal vapor generated from the magnetic poles 4a and 4b from adhering to the inner wall of the insulating container 2.

Next (2) A method for manufacturing a vacuum valve having the above structure (two explanations will be given). First (=, the contacts used in the present invention will be explained with reference to Figure 2.
r) With a sintered body of 11 and copper (Cu) 12, a thin film of copper (eu) 13 and C' 14 was deposited on one surface of this sintered body The thickness of this thin film is selected depending on the surface melting conditions to be performed later and the required time characteristics of the contact, but it is reasonable to set it to 100 μm or less. .If, 4
If the film is thick, it will be disadvantageous in practice, as it will require a large amount of energy and the melting time will be long after the subsequent surface melting. Then, braze the magnetizing shaft 5a to the above-mentioned contacts so that the component ratio becomes an appropriate value (select 2).In addition, when cutting off the 4 currents, a coil may be installed to drive the arc-containing current. However, this is omitted in this embodiment.
-' Brazed in a vacuum of Torr or more, and solder sealing part 1
Get 5a. In order to improve the reliability of this brazing $15a (=, 1m (Cu)/brazing may also be attached to the round. The same applies even if there are two magnetic shafts 5bl). Then, the sintered body 10 is brazed. After this brazing, the pass-through shaft 5a is brazed to the end plate 3a, and the magnet-passing shaft 5b is brazed to the end plate 3b via the bellows 6.

Next (=, upper magnetic axis 5ai= thin film surface of copper (Cu) 13 and chromium (Cr) 14 of brazed sintered body 10 (=heat source with high energy density such as electron beam or laser) In FIG. 4, the beam 17 emitted from the single gun 16 is
A thin film of u) and chromium (Cr) is irradiated and melted. In addition, the reference numeral 18 shown in the same figure is a cable that applies high pressure to the Zeko gun 16, and 19 is a cable that applies the electron beam 17 (two-stranded steel (C)).
This shows the melted and solidified portion of the thin film of u) and chromium (Or).

The metal structure of this molten and solidified part is rapidly melted and solidified by the high-energy-density forceps beam 17, so the metal structure is a very fine mixture of chromium (Cr) and copper (Cu). Furthermore, since the electron beam 17 is irradiated in a vacuum at a temperature of 10-'Torr or more, the melted and solidified part is in an extremely clean state with seven faces. (It's turning.

This cleanliness contributes to improving the 1δ reliability of the contact, which will be described later. Similarly, in the case of the magnetization shaft 5b17), the thin film of m(Cu) and chromium (Or) of the sintered body 10 (-C melted and solidified by irradiating the sintered body 10 with the Niyako beam 17).Next (2) The end plate 3a and the insulating capacitor 42, which are partially assembled with the magnetic shaft 5a and the arc shield 7fl attached, are
-' Braze and seal in a commercial vacuum of Torr or more.

In the case of the end plate 3b (L)), the magnetic shaft 5b is attached via the bellows 6t and partially assembled, but the P3 edge plate 2 is similarly soldered and sealed.

Since it is manufactured in this way, the contact surface (two sets (Cu))
It is possible to obtain a true wall bulb in which contact metal 1- is formed in which chromium (Cr) is extremely finely crystallized, and the surface of the contact metal 1- is extremely free from contamination.

In addition, in the above explanation, the adhesion J- on the surface of the contact is replaced with copper (C
u) is two layers and chromium (Cr) is i7-, but copper (C
u) may be set to 1 no, steel (Cu) and chromium (Cr
) The alloy layer may be attached (d).Also, the method of attachment may be any method other than vacuum deposition (=, plating, thermal spraying, pressure 4, etc.).

Next, for comparison, an experimental chestnut in which unexploded iJA was chewed will be explained together with a reference example in which two tests were performed.

Using chromium (Cr) with a particle size of approximately 100 μm, 30 wt.
After pre-sintering the chromium (Cr) skeleton at 1150°C in hydrogen,
Two sets of final curves (ACCu containing 40% chromium (Cr))-chromium (Cr) fittings were fabricated by infiltrating copper (Cu) at 1150'C in hydrogen. Of these, one set was re-degreased and cleaned (2) using the conventional method (2-9 magnetic shaft (2J4L4), and then vacuum sealed to create a vacuum valve (Reference Example 1)
. The other set was degreased and cleaned and attached to the lead shaft, and then the surface of the copper (Cu)-chromium (Cr) paste alloy (=, copper (Cu) and am (Cr) thin film is deposited at +30/Am, then the thin film is melted and alloyed by an electron beam, and is integrated with the above 40% chromium (Cr)-copper (Cu) pace alloy. Experimental example 1) to produce vacuum pulp by sealing
. In addition, the electron beam was irradiated with an accelerating magnetic pressure of 30 KV and a beam overflow of 50 mA.

The welding resistance of these is shown in Table 1 (2).

As is clear from Table 1, the welding resistance of Example 111, which was subjected to electron beam (secondary surface treatment), was significantly improved. = Refinement iL, copper (C
u) The effect that the probability of contact between comrades has decreased significantly (this is thought to be due to two factors).

Next, the conditions of active current on the second surface of the contacts of Experimental Series 1 and Reference Example 1 immediately before vacuum sealing were compared using the contact resistance method.

Here, C1 Reference Example 2 has the same contact as Reference Example 1 (2 Example 1
It was irradiated with a magneton beam under the same conditions as .

These contact resistances are shown in Table 2.

As can be seen from Table 2, Reference Example 1 had a lot of high quality contact resistance, while Experimental Example 1 had none at all. Also, from Reference Example 2, the effect of the thin film is clear. Correspondingly, the high pressure resistance is also low. In Experimental Example 1, copper (Cu)
The chromium (Or) thin film has a valley of J μm, but if the valley is more than 100 μm, the efficiency of melting and sound reinforcement by the magneton beam is poor, and sufficient uniform miniaturization cannot be obtained. or,
Since it is difficult to adjust the composition after integration with the pace alloy, the thickness is preferably 100 μm or less.

In addition, (2) 4-layer resistance (2) Disc-shaped contact samples with an outer diameter of 25I8 (2) IC4 with spherical pressure ronds with a radius of 11001t at the tip facing each other in the order of outer diameter 25
m in A air of 10-% lfi Hg with a load of I applied.
There is a half-wave υiE L of the Hz, 18 KA torrent, and 1 added by the contact tripping force at that time C. Regarding the contact resistance, a platinum probe with a spherical tip and a diameter of 1 IJl was moved over the surface of the contact, and a distance between the contact and the deep needle (2 l) was measured.
mA it vif: lli when t-flowed is shown. Resistance to static emphysema (secondly, buff polishing): A nickel wire anode with a diameter of 5 mm was polished to a mirror-like surface, and the above contact point was used as a peg. Shows the pressure when raised and a spark is generated.

[Effect of the invention J Since the book @ Ming is composed of 42 as described above, (1)
Since chromium (Cr) oxide is not formed on the contact surface and is not activated, the contact resistance does not increase.

(2) The contact surface has extremely fine (bidispersed) metal fibers of copper (Cu) and chromium (Or), so the welding resistance is excellent.

It is possible to produce vacuum pulp with many advantages such as

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the structure of Group A pulp related to the present invention, FIG. 2 is a sectional view of a contact point according to an embodiment of the present invention, and FIG. FIG. 4 is a cross-sectional view showing a state in which the magnetic shaft is fixed, and FIG.
FIG. 3 is an explanatory diagram showing a method of four-melting and solidifying a film. 1... Vacuum container, 3a, 3b... End plate 4a+ 4
b... Lupole, 5a, 5b... Threaded shaft 10... Sintered body, 11... Chrome grain 12... Octopus, 13...
・Thin copper film 14... Thin film of chromium 17... Single beam (87
33) Agent Patent attorney Yoshiaki Inomata (one person) Figure 1 Figure 2 Figure 3

Claims (1)

[Scope of claims] Copper (100 μm or less) is deposited on the surface of a sintered body of copper (Cu) and chromium (Or).
Cu) or chromium (Cr) alone or alloy layer so that the final surface layer is ii'l (Cu) (knee j
- After attaching more than that, high energy 6! A method for producing vacuum pulp, which comprises heating and alloying with a heat source having a temperature of i. L2) A special N'F claim in which a single layer or an alloy layer of jI+1 (Cu) or chromium (er) is formed on the surface of a sintered body (=1 = taliL) by vaporizing, plating, spraying, or pressure bonding. 4th Item 1. Method for producing convex vacuum pulp. (3) Copper (Cu) I on the surface of the contact that is fixed to the cage shaft.
li! The method for producing a pulp according to claim 1, characterized in that the pulp is made to adhere to a pulp.