JPH11232971A - Vacuum circuit breaker, vacuum pump and electrical contact used in the same, and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve uniform dispersion characteristic of minute chromium particles and the like in an electrode member to reduce dispersion in a breaking function and a withstand voltage function by providing a highly conductive metal and a fireproof metal with a melting point which is higher than that of the highly conductive metal in an arc electrode member and containing a specific quantity of fireproof metal with a specific grain size in the fireproof metal. SOLUTION: A metallic powder is constructed of highly conductive metal powder, such as Cu powder and one or more kinds of fireproof metal powder such as Cr, W, Mo, Ta powder. This mixture powder is sintered by one method in hot pressing, HIP, and a discharge sintering method, or alternatively a fireproof metal molding body is infiltrated with a highly conductive metal. The fireproof metal contains particles with a grain size of 5-60 μm at a ratio of 70 wt.% or more. An arc electrode 1, an arc electrode supporting part 2, an external conductor connection part 3, and a back conductor 4 are integrally structured, and between the arc electrode 1 and the arc electrode supporting part 2 provided with equal thickness, the back conductor 4 with a diameter smaller than those of these is arranged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel vacuum circuit breaker, a vacuum valve used for the same, an electric contact used for the same, and a manufacturing method.

[0002]

2. Description of the Related Art An electrode structure in a vacuum circuit breaker includes a pair of fixed electrodes and a movable electrode. The structure of the fixed and movable electrodes includes an arc electrode, an arc supporting member for supporting the arc electrode, a coil electrode material connected to the arc supporting member, and an electrode rod at an end of the coil electrode.

[0003] The above-mentioned arc electrode material is directly exposed to an arc to open and close a high voltage and a large current. Satisfactory characteristics required of the arc electrode are a large breaking capacity and a high withstand voltage value. That the contact resistance value is small
(Excellent electrical conduction), excellent welding resistance, low contact wear, and small cutting current value. However, it is difficult to satisfy all of these characteristics, and in general, a material that emphasizes particularly important characteristics according to the application and sacrifices other characteristics to some extent is used. As a material for an arc electrode for interrupting a large current and a high voltage, Japanese Patent Application Laid-Open No. 63-96204 discloses a method of infiltrating Cu into a Cr or Cr-Cu skeleton. A similar manufacturing method is disclosed in Japanese Patent Publication No. 50-2167.
It is also disclosed in Japanese Patent Publication No. 0.

In Japanese Patent Application Laid-Open No. Hei 6-330101, a copper-chromium material is used. The copper powder and the chromium powder are blended so that the chromium powder is 5 to 50% by weight, mechanically alloyed in an inert gas atmosphere, the obtained mechanically alloyed powder is cold-formed, and the compact is hydrogenated. Sinter at 500 ° C or higher in gas or vacuum, and
It describes cold forging below 0 ° C. and then resintering the forged material above 500 ° C. to produce a copper-chromium composite with a true density ratio of 96%. Japanese Patent Laid-Open No. 3-266319 discloses a method for producing a contact material by mechanical animation.

[0005] A mixture of chromium powder and copper powder is formed as a sintered body by powder metallurgy, or a porous chromium pre-sintered body is infiltrated with copper to form an infiltration material, What was formed as a smelting material by the method is used. However, since the bonding force between the metal particles of the porous mixed metal molded body produced by these techniques is weak, there is a problem in handling such as handling of the molded body. In addition, the chromium particles with weak bonding force, which are lone-resistant metals, in the composite in which the compact is melt-impregnated with copper, which is a highly conductive metal, are lightly floated and floated to the electrode support (copper). Dechromation phenomenon of the penetration composite material is observed. In addition, the phenomenon of unevenness being eroded at the interface between the arc electrode portion (composite member) and the electrode support portion is remarkable. Further, the molded article may be reduced in wall thickness or the composition may be non-uniform, which may deteriorate the performance as an electrode member for a vacuum circuit breaker.

[0006]

In a copper alloy used as an electrode material, chromium or the like is generally added to improve welding resistance and voltage resistance. But,
Molded articles molded with large chromium powder particles are brittle. In addition, the infiltrated electrode material may cause unevenness to be eroded at the interface between the arc electrode material and the electrode support material, and may reduce the thickness.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, improve the uniform dispersibility of fine chromium particles and the like in a copper matrix constituting an electrode member, and reduce the variation in the breaking performance and withstand voltage performance of a vacuum circuit breaker. An object of the present invention is to provide a vacuum circuit breaker, a vacuum valve, an electric contact, and a manufacturing method for the vacuum circuit breaker, which can be reduced and improve the reliability of the vacuum circuit breaker.

[0008]

SUMMARY OF THE INVENTION According to the present invention, a composite member (arc) is produced by making copper and chromium powder or the like fine by a mechanical grinding method using a ball mill, and further forming a compact by a discharge sintering method. There is no erosion at the interface between the electrode (electrode) and copper (arc electrode support member), and the molded article undergoes less wall thinning during infiltration, and electrical characteristics superior to conventional copper alloys can be obtained.

The present invention relates to a method of sintering a compact formed by pressure discharge sintering (PAS) using a metal powder obtained by dispersing fine copper particles and fine chromium particles by a ball mill method. Preferably, copper is infiltrated.

The present invention relates to an alloy powder comprising a highly conductive metal powder such as Cu and one or more refractory metal powders such as Cr, W, Mo and Ta. Refractory metal powders such as Cr, W, Mo, Ta, etc. having a particle size of 5 to 60 μm as compared to powders have a weight percentage of 70% by weight or more, preferably 80% by weight or more, more preferably 90% by weight or more. It is.

The alloy comprises Cr having a melting point of 1800 ° C. or more,
The total of one or more refractory metals of W, Mo, and Ta is 20 to 80% by weight, and a highly conductive metal such as Cu is 20% by weight.
It is desirably about 80% by weight.

In the above alloy, the content of Pb is 10% by weight or less,
The total of at least one metal of b and Bi can be added at 10% by weight or less, and Ti can be added at 10% by weight or less.

According to the present invention, the mixed powder is hot-pressed,
It is obtained by sintering using either HIP or spark sintering, or by infiltrating a highly conductive metal into a refractory metal molded body.

According to the present invention, there is provided a vacuum valve provided with a fixed electrode and a movable electrode in an insulating container, and each of the fixed electrode and the movable electrode in the vacuum valve is connected to the outside of the vacuum valve. And a switching means for driving the movable-side electrode via an insulating rod connected to the movable-side electrode, wherein the fixed-side electrode and the movable-side electrode are made of a refractory metal. A vacuum circuit breaker having an arc electrode made of the above-mentioned alloy with a conductive metal.

The electrode material is composed of a composite alloy of a refractory metal and a highly conductive metal mainly composed of Cu or the like.
A high melting point refractory metal such as W, Mo, Ta or the like having a melting point of about 1800 ° C. or higher is used, and a small solid solution amount of 3% or less in Cu is preferable.

The refractory metal is 20 to 80% by weight, in particular 55%
It is desirable that the alloy contains 75 to 75% by weight of Cu and 25 to 45% by weight of Cu. It is particularly preferable that the refractory metal contains 1 to 10% by weight, based on Cr, of one or more of Nb, V, Fe, and Co.

The arc electrode is made of Cr, W, Mo and Ta.
Or a mixture of two or more of the above, a highly conductive metal consisting of one of Cu, Ag and Au or a highly conductive alloy mainly containing them, and one or two of Pb, Bi, Te and Sb It is preferable that the electrode support is made of the above alloy, and the electrode support is made of the highly conductive metal or alloy.

The electrode support, the back conductor and the external conductor connection are Cr, Ag, W, V, Nb, Mo, Ta, Zr, S
It is preferable that one, two or more of i, Be, Ti, Co, and Fe be made of an alloy of Cu, Ag, or Au with a total amount of 2.5% by weight or less.

The arc electrode in the present invention is made of a composite alloy of a highly conductive metal impregnated in a porous refractory metal, and the arc electrode and the electrode support, the back conductor and the external conductor connection are preferably the high conductivity metal. It is preferably formed integrally by melting the metal. The electrode support in the present invention has a 0.2% proof stress of 10 kg / mm ² or more and a specific resistance of 2.8 μΩc.
m or less is preferred.

In the present invention, the fixed-side electrode and the movable-side electrode are provided with a perfect circular concave portion at the center of the arc electrode portion in contact with each other.

It is preferable that the arc electrode, the electrode supporting portion, the back conductor, and the external conductor connecting portion are integrally formed by solidification of the highly conductive metal by solidification by fusion or powder metallurgy.

A plurality of arc electrodes and electrode support portions;
Preferably, three to six spiral slit grooves or linear slit grooves are provided.

The plurality of slit grooves reaching the electrode side surface from the outer peripheral end side extending from the central portion side to the outer peripheral side of the electrode of the present invention are a plurality of arc running surfaces formed between the slit grooves and the slits. The two arc running surfaces are integrally connected to each other across the slit groove between the groove outer peripheral side and the arc running surface outer peripheral end, and the path of the current flowing from both arc running surfaces is one-side arc running surface is the other side arc. A connecting portion having the same resistance value as the two arc running surfaces longer than the running surface, wherein a cross-sectional area of the connecting portion is adjusted to control a current flowing from the both arc running surfaces to the connecting portion. Is preferred.

Further, the present invention includes the above-mentioned slit groove,
D ₂ / D of outer diameter D ₁ and inner diameter D ₂ of the connecting portion
It is preferable that the relationship of ₁ is greater than 0.9 and the width is less than 1.

Further, the present invention includes the above-mentioned slit groove,
It is preferable that the thickness of the connecting portion is set in a range of 0.5 (mm) to 5 (mm).

Further, in the present invention, it is preferable that the radius surface formed on the outer peripheral end of the arc running surface is set in a range of 0.5 (mm) to 1.5 R (mm).

The R surface formed on the outer peripheral end of the connecting portion is set to be 0.1 mm.
It is preferable to set the thickness in the range of 5 (mm) to 1.5 R (mm).

Further, according to the present invention, the thickness of the connecting portion is in the range of 0.5 (mm) to 5 (mm), and the radius surface formed at the outer peripheral end of the arc running surface is 0.5 (mm). It is preferable to set each in the range of ~ 1.5R (mm).

According to the present invention, there is provided a vacuum valve having a fixed side electrode and a movable side electrode in an insulating container, and each of the fixed side electrode and the movable side electrode in the air valve is connected outside the vacuum valve. A conductive terminal, and opening and closing means for driving the movable-side electrode via an insulating rod connected to the movable-side electrode, wherein the fixed-side electrode and the movable-side electrode are the refractory metal described above. An arc electrode made of an alloy having particles and a highly conductive metal, and an electrode support made of a highly conductive metal that supports the arc electrode, wherein the arc electrode and the electrode support are made of the highly conductive metal. The insulating container is cylindrical and has a rated voltage (k
V) and the value (y) obtained by multiplying the effective value of the cut-off current (kA) are within the range of values obtained by the following expressions (1) and (2) from the outer diameter x (mm) of the insulating container. It is characterized by.

Y = 11.25x-525 (1) y = 5.35x-242 (2) In the present invention, the diameter y (mm) of the arc electrode is defined as a rated voltage (kV) and an effective value of a breaking current ( kA) and x
(KVA × 10 ³ ) and is characterized by being within a range of values obtained by the following equations (3) and (4).

Y = 0.15x + 22 (3) y = 0.077x + 20 (4) In the present invention, the insulating container is a cylinder, and the outer diameter y (mm) of the insulating container is the diameter x of the arc electrode. (Mm) within the range of values determined by the following equations (5) and (6).

Y = 1.26x + 10 (5) y = 1.26x + 30 (6) There are three sets of the vacuum valves for three phases, and these three sets of vacuum valves are arranged side by side by a resin insulating cylinder. It is preferable that they are integrated.

The present invention also relates to a vacuum valve provided with a fixed electrode and a movable electrode in an insulating container maintained in a high vacuum, wherein the two electrodes are made of the above-mentioned refractory metal particles and a highly conductive metal. , More preferably, an arc electrode made of a composite member containing a low melting point metal, an electrode support portion made of a highly conductive metal supporting the arc electrode, a back conductor smaller in diameter than the electrode support portion, and the back conductor An arc conductor, an electrode support, a back conductor, and an external conductor connection are formed integrally with the highly conductive metal.

The structure of the electrodes of the vacuum valve according to the present invention is the same as described above.

According to the present invention, there is provided an arc electrode made of an alloy containing the above-mentioned refractory metal particles, a highly conductive metal and preferably a low melting metal, and an electrode support made of a highly conductive metal for supporting the arc electrode. Having a back conductor smaller in diameter than the electrode supporting portion and an outer conductor connecting portion larger in diameter than the back conductor,
The electric contact is characterized in that the arc electrode and the electrode support, the back conductor, and the external conductor connection are integrally formed by melting or solid-phase diffusion bonding of the highly conductive metal.

In the method for producing an electric contact according to the present invention, the arc electrode is obtained by placing the highly conductive metal on a porous sintered body having a refractory metal having the above-described particle size, Is formed by melting or solid phase diffusion bonding and infiltrating or diffusion bonding in the porous body, and the thickness or high conductivity of the highly conductive metal remaining after the infiltration after the electrode support portion. It is preferable to form the metal portion by setting it to a required thickness after the electrode support portion. In particular, in the infiltration of the present invention, during sintering of the above-described porous body, the metal is turned into refractory metal particles and highly conductive metal particles by heating in a solid state near the melting point of the low melting metal for a sufficient time. The diffusion bonding is performed to prevent the low melting point metal from falling off during infiltration. The heating temperature is 30 from the melting point.
It is preferable to heat at a temperature lower by １００100 ° C.

In the infiltration of the present invention, the arc electrode and the electrode support are formed by infiltrating and solidifying the high-conductive metal and then maintaining the desired temperature at a desired temperature. It is preferable to have a heat treatment step of precipitating a metal or an intermetallic compound which is dissolved in supersaturation in the solution.

The electric contact can be used for a fixed electrode or a movable electrode of a vacuum valve.

The electrode structure of the vacuum circuit breaker includes an arc electrode, an arc electrode supporting member, a back conductor, and a connection portion for an external conductor. The arc electrode is formed of a composite alloy of a refractory metal having the above-described particle size and a conductive metal. The former includes Cr, W, Mo,
A metal having a high melting point of about 1800 ° C. or more, such as Ta, is used.
It is preferable that the amount of solid solution in Cu, Ag, and Au as the highly conductive metal is as small as 3% or less. Pure Cu is particularly preferred after the arc electrode supporting member, but because of its low strength, these members are reinforced with pure iron or stainless steel as an anti-deformation measure to prevent electrode deformation.

The refractory metal is 20 to 80% by weight, particularly preferably 35 to 65% by weight, and one of Cu, Ag and Au or an alloy mainly composed of these, 20 to 80% by weight, preferably 3 to 80% by weight.
An alloy containing 5 to 65% by weight and Pb or the like at 1% by weight or less, preferably 0.1 to 0.6% by weight. It is preferable to use a composite material in which a highly conductive metal is melt-impregnated in a porous sintered body containing a conductive metal. In addition, a two-layer structure of the arc electrode and the electrode support portion and thereafter is provided, and the electrode support portion and subsequent portions are for reinforcing and supporting the arc electrode, and preferably have a thickness of at least half of the thickness, and particularly preferably have a thickness equal to or more than that. preferable.
The porous sintered body preferably has a porosity of 50 to 70%. In particular, the refractory metal is used in an amount of 0.1 to 10% by weight, preferably 0.5 to 10% by weight with respect to Cr, in order to enhance the withstand voltage characteristics.
It may contain one or more of Nb, V, Fe, Ti, and Zr at 2% by weight.

The arc electrode of the present invention is particularly suitable for
60%, Nb 0.5-5.0%, preferably 0.5-3.0
% And Pb 0.1 to 0.5%.

According to the present invention, the arc electrode material and the members subsequent to the arc electrode support member have a monolithically continuous structure. As a result, the above-mentioned slit groove can be formed up to the arc electrode support portion, and the problem caused by the conventional brazing due to the heat generated by the arc at the time of interruption does not occur, so that it is possible to reduce the size and to interrupt the high current. Was.

Further, according to the present invention, the arc electrode material, the arc electrode supporting member, and the outer conductor connecting portion coil electrode material constituting the electrode are formed as a monolithically continuous monolithic structure and at the same time as the monolithically structured electrode. The highly conductive metal formed after the arc electrode support member formed in the same process as the manufacturing process includes 0.0.
1 to 2.5% by weight of Cr, Ag, W, V, Zr, Si,
One or more of Mo, Ta, Be, Nb, Ti
It is possible to use those contained in u, Ag, and Cu. Therefore, the mechanical strength, particularly the proof stress, can be greatly increased without significantly lowering the electrical conductivity of the material after the arc electrode supporting member. As a result, it is possible to sufficiently cope with an increase in the contact pressure between the electrodes and the impact force at the time of opening and closing the electrodes, and it is possible to solve temporal deformation.

As described above, the conventional electrode structure is obtained by combining the arc electrode material and the arc electrode support member and thereafter with the unified and metallographically continuous integrated structure and the high strength of the core member. As a result, a highly reliable and safe vacuum circuit breaker in which adverse effects are eliminated can be provided.

According to the infiltration method of the present invention, Cr,
W, Mo, Ta powder and Pb, Bi, Te, Sb powder and C
u, Ag, Au powder or other arbitrary metal particles are mixed into a predetermined composition, and the mixed powder is molded so as to have a predetermined void content and then sintered to form a porous sintered body. Thereafter, a block made of pure Cu, Ag, Au, or an alloy thereof is placed on the sintered body and melted to infiltrate the voids of the porous sintered body with a metal such as pure Cu or a Cu alloy. At this time, the molten infiltrant is alloyed to have the above-mentioned content by positively utilizing the liquid phase diffusion of the constituent elements of the sintered body into the molten infiltrant. The ingot after completion of infiltration is processed into an electrode having a predetermined shape.

In the infiltration of a highly conductive metal, the amount of the porous metal dissolved in the highly conductive metal can be controlled by the infiltration temperature and the holding time. Then, the temperature and time are set.
Of course, an alloy in which an alloy element is added to a highly conductive metal in advance can also be used.
As a result, a material having high strength and a low specific resistance can be obtained, so that a material having high performance can be obtained.

As described above, the electrode of the present invention can be formed in a desired shape by a combination of infiltration and casting techniques in a desired shape, but can be obtained by cutting as the final shape described above.

According to the present invention, a fine metal mixed powder is spark-sintered,
It is characterized by being formed by using any one of hot press, HIP and compacting.

In manufacturing an electrode member for a vacuum circuit breaker, a highly porous mixed metal compact produced by a conventional powder compacting method has a very weak bonding force between particles, and is difficult to handle. Further, the composite member obtained by melting and impregnating the above-mentioned molded body with a copper-based or silver-based metal which is a highly conductive component has a non-uniform composition due to dechromization in which chromium of the molded body melts into copper, or erosion at the interface of the infiltrated portion. Phenomena such as wall thinning are not preferred.

The above problem is solved by the electrode member for a vacuum circuit breaker of the present invention.

In the present invention, one or two of copper, gold, and silver, which are high conductive components, one or two of chromium, tungsten, molybdenum, and iron, which are lone components, are subjected to a ball milling method. Metal powder composed of at least one of niobium, vanadium, titanium, tantalum, zirconium, and silicon, which are effective particles. In addition, copper, gold,
One or two kinds of silver, one or two kinds of chromium, tungsten, molybdenum, and iron as lone components, and one of runiobium, vanadium, titanium, tantalum, zirconium, and silicon that are effective for withstand voltage. As described above, it is preferable to use one or two or more metal powders of the welding resistant component and the low melting point material of lead, bismuth, antimony, and tellurium. The metal powder is stored together with an iron ball, and by pressing the iron container for a long time, a pressing force sufficient to plastically deform the metal powder due to the centrifugal force of the iron ball is given, and the metal powder is finely pulverized. A method for producing a metal powder for an electrode member for a vacuum circuit breaker, which comprises applying a sufficient pressing pressure to uniformly and uniformly disperse and mix the powder, and finely pulverizing the metal powder and uniformly dispersing and mixing the metal powder. . As the crushed particles become finer, sufficient effects such as withstand voltage, welding resistance and cutoff characteristics can be obtained. However, in consideration of productivity and economy, particles that are fox-resistant components are 53%.
μm or less is preferred. The content is 20 to 60% by weight of the lone component with respect to the high conductive component, and 1 to 5% of the withstand voltage component.
10% by weight, and the content of the anti-welding component is preferably 0.1 to 1% by weight.

According to the present invention, there is provided a method for manufacturing an electrode member for a vacuum circuit breaker, wherein the metal powder finely pulverized by a ball mill is manufactured by a discharge sintering method to form a highly porous molded body having a strong bonding force. is there. Unlike the conventional powder compact, the compact has a strong bonding force between the fine metal powders, so that handling such as handling is easy. The density of the highly porous molded body produced by the PAS method is as follows:
It can be arbitrarily selected by changing the sintering time, etc.
The porosity is preferably 40 to 70%. The production time of the compact is also short.

In the present invention, the composite member obtained by melting and impregnating the highly porous molded body with a metal as a highly conductive component dissolves into copper (electrode supporting portion) without releasing chromium particles and floating. Alternatively, a phenomenon such as wall thinning due to erosion of the interface with the infiltration part can be significantly prevented, and a sound electrode member for a vacuum circuit breaker in which fine highly isolated metals are uniformly dispersed in highly conductive metal can be provided.

According to the present invention, chromium, tungsten,
Molybdenum, tantalum powder, lead, bismuth, tellurium, antimony powder and copper, silver, gold alloy powder or any other metal particles are mixed in a predetermined composition, and the mixed powder is porous so as to have a predetermined porosity. A molded body is produced. afterwards,
A block made of copper, silver, gold, or an alloy thereof is placed on the compact and melted to infiltrate voids of the porous compact with a metal such as copper or a copper alloy. At this time, the molten infiltrant is alloyed to have the above-mentioned content by positively utilizing the liquid phase diffusion of the constituent elements of the molded body into the molten infiltrant. The ingot after completion of infiltration is processed into an electrode having a predetermined shape.

In the infiltration of a highly conductive metal, the amount of the porous molded body dissolved in the highly conductive metal can be controlled by the infiltration chamber and the holding time, and in particular, the specific resistance and strength to the electrode support and the coil electrode. The temperature and time are set in consideration of the above. Of course, an alloy in which an alloy element is added to a highly conductive metal in advance can also be used. As a result, a material having high strength and a low specific resistance can be obtained, so that a material having high performance can be obtained.

[0056]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (Example 1) Niobium powder 2.0 having a particle diameter of 150 μm or less, purity 99.99%, 40.0% by weight, particle diameter 75-45 μm, purity 99.9%.
In this method, a mixed powder with a weight% is finely pulverized by a high energy SUS304 ball mill, dispersed and mixed. The pulverization by a ball mill is performed at 100-200 ° C. in a SUS304 iron ball mill container containing mixed powder and SUS304 iron balls.
And at the same time, the inside of the container is 10 ⁻² to 10 ⁻³ Torr.
Degassing treatment was performed, followed by purging with an argon gas or a nitrogen gas having a purity of 99.9% or more, and thereafter, a mechanical pulverization / mixing treatment was performed at room temperature around 150 to 200 rpm for 10 to 120 hours. The mixed powder was classified by a sieve, and a powder having a size of under 53 μm was used.

The classified finely pulverized mixed powder obtained by the mechanical pulverization and mixing treatment has a particle size of 150 μm or less and a purity of 99.99.
% Of electrolytic copper powder, mixed in the same manner by a ball mill, filled in a graphite die, sandwiched between upper and lower punches also serving as electrodes, evacuated the container to 5 × 10 ^-2 Torr, and adsorbed to the powder and the like. The gas and the like are removed, and the powder is pressed at a molding pressure of 8000 kg / cm ² . Subsequently, by applying a pulse current,
After the oxide on the powder surface is removed and activated, a direct current of 2600 A is applied to sinter the finely ground mixed powder. The shape of the molded body is 40 mm in diameter and 9 mm in thickness. The porosity of the molded body was 70% after 10 hours of mixing, 65% for 30 hours, 60% for 50 hours, and 55 for 80 hours.
%, 100 hours 50%, 110 hours 45
% And 120% for 120 hours.

FIG. 1 shows the yield of fine powder having a particle size of 53 μm or less produced in Examples 1 to 7 of the present invention. The yield of fine powder having a particle size of 53 μm or less increases with MG time, and is a 78% yield in 100 hours. However, when the time exceeds 100 hours, a granulated form is obtained, and the yield of fine particles is deteriorated. The MG time is preferably 50 to 100 hours. In particular, 100 hours with a high yield of fine powder having a particle size of 53 μm or less is more preferable.

The Cr powder in this embodiment has a particle size of 5 to 53.
μm has about 95% or more by weight, and those with a particle size of less than 5 μm are only 5% or less. In addition, particle size 22 ~
Those having a size of 53 μm are 60 to 90% by weight, and those having a particle size of 22 μm can be obtained by classification.
It is more preferable to make the particle size smaller than 90% by weight for particles having a size of 22 μm or less and 10% by weight or less for particles having a particle size of not more than 10% by weight in order to enhance the blocking characteristics.

Further, a particle size of 150 μm or less is added to the above powder.
Similar powders and compacts can be obtained by adding a 99.99% pure electrolytic copper powder and subjecting it to mechanical pulverization and mixing.

FIG. 2 is a cross-sectional view showing a method of manufacturing an integrated electrode according to the present invention using the above-mentioned molded body. In the figure, a finely ground mixed metal compact is placed in a lower part of a graphite mold, and copper for infiltration is placed thereon. The finely pulverized mixed metal powder is molded at a molding pressure of 2.0 using a mold having a diameter of 80 mm.
A molded product having a diameter of 48 mm and a thickness of 9 mm was produced at ton / cm ² . The molded body had a porosity of about 70%, and was sintered at a sintering temperature of 1050 ° C. for 120 minutes in a vacuum of 10 ⁻⁵ Torr or less. In heating to 1050 ° C., the material was kept under a solid phase near the melting point of lead for a long time, and then heated to a predetermined temperature. The porosity at this time is 65%. 90mm inside diameter, 100 outside diameter
The porous sintered body was placed at the center of the lower surface of a graphite mold having a height of 100 mm and a height of 100 mm, and copper for infiltration made of pure copper having a diameter of 80 mm and a length of 100 mm was placed thereon. As the copper for infiltration, a member made of an infiltration material having a diameter of 28 mm and a length of 25 mm and copper forming a feeder portion was provided. The side surfaces of the two members made of a graphite container and pure copper and the upper portion of the member serving as the infiltration material and the feeder are filled with Al ₂ O ₃ powder. The infiltration conditions were as follows: a sintering temperature of 1 × 10 ⁻⁵ Torr in vacuum.
The mixture was held for 150 × 60 minutes to melt copper, and the infiltration material was uniformly infiltrated into the skeleton of the porous mixed metal molded body, and then allowed to cool and solidify in a vacuum. FIG. 3 is a cross-sectional appearance of an ingot taken out of a graphite container after solidification.

FIG. 4 shows the arc electrode 1, the arc electrode support 2, the external conductor connection 3, and the back conductor 4 after cutting. As a result of observing a microstructure photograph of a cross section of the interface between the arc electrode 1 and the arc electrode support 2 after cutting, the structure of the present invention shows that fine chromium particles are uniformly distributed in a copper matrix. In addition, the structure of the product which had a smooth interface state and was simply compacted without spark sintering had an interface configuration in which large chromium particles were distributed and the unevenness was large.

As described above, according to the method of the present invention, the arc electrode 1, the arc electrode supporting portion 2, the external conductor connecting portion 3, and the back conductor 4 are integrally formed. The arc electrode 1 and the arc electrode support 2 have the same thickness, and a back conductor 4 having a smaller diameter smaller than these is provided between the two. In addition, the interface between the arc electrode material and the arc electrode support member is completely integrated in a metallographic manner, and it can be seen that joining by brazing or the like is unnecessary. Further, as a result of analyzing the Pb of the cross section of the arc electrode 1, Pb was uniformly dispersed.

By using three molds, three molds can be manufactured at a time. Not only three but also a desired number can be manufactured at a time.

As shown in FIG. 4, the electrode obtained by cutting has a boundary layer between the arc electrode support portion 2 and the arc electrode 1 formed of an alloy. It is strong against arcing and can contribute to the improvement of the current breaking capacity together with the above.

FIG. 5 shows the thickness reduction of the arc electrode 9 after the melt impregnation. The thickness of the member according to the present invention is 1.5 m 2, whereas that of the conventional member is greatly reduced to 3.0 mm. For this reason, the member of the present invention is a good member in which the composite member (arc electrode) does not erode even by infiltration.

(Embodiment 2) FIG. 6 is a sectional view of a vacuum bulb using an arc electrode according to the present invention. An upper and lower integrated seal ring 27 is provided in the upper and lower openings of the insulating cylinder 8 made of an insulating material to form a vacuum chamber that forms a vacuum chamber. The electrode rod on the movable side, which forms a part of the movable electrode 23 in the middle of the seal ring located immediately below the electrode rod 24 on the fixed side, is formed. Is provided so as to be movable up and down so as to be in contact with and separate from the arc electrode of the movable electrode 23 with respect to the arc electrode 2 of the fixed electrode 21, and a metal is provided inside the seal ring located around the movable electrode rod 24. A bellows 26 made of stainless steel is provided so as to be extended and contracted, and a sealing member 25 made of a metal plate having a cylindrical shape is installed around the two arc electrodes by a vacuum vessel of an insulating cylinder 28. 25 is the insulating cylinder 28 So as not to impair the insulating properties of the empty container is obtained by configuration.

[0068]

[Table 1]

Samples A to K shown in Table 1 are examples of the present invention.
Samples L to O are comparative examples.

In the breaking test, a pair of test electrodes are assembled in a breaking test section, and baking is performed at 300 ° C. for 2 hours while evacuating the breaking test section. After that, gap 2.5mm
While applying an AC voltage of 60 kV at the maximum between the electrodes, conditioning is performed twice to remove a low withstand voltage portion that is easily discharged. In the impulse withstand voltage test after the interruption of the small current of 300 A, the minimum discharge voltage at the electrode gap of 2.5 mm is measured after performing 10 arc firings at 100 V AC and 300 A. This firing 10 times and the withstand voltage measurement were repeated 10 times to obtain the withstand voltage characteristics after the interruption of the small current. In the cutting current measurement, the current waveform at the time of interruption was stored in a digital memory and then reproduced on a synchroscope to read the cutting current value. This was repeated 50 times to obtain the maximum value and the average value.
In the cutoff test, the LC resonance circuit equipment was used, the cutoff current frequency was set to 58 Hz and the transient recovery voltage frequency was set to about 11 Hz in view of the circuit constants, and the test voltages 1 to 5. The test was continued in the range of 6 kV until the cut-off was impossible.
If the interruption cannot be performed during the test, the interruption current is lowered, the interruption test is performed, and the electrode surface is cleaned. And In the impulse withstand voltage measurement after interrupting the large current, the electrode gap is 2.5 mm after the test.
The minimum impulse withstand voltage was measured, and the withstand voltage characteristics after the interruption of the large current were determined. A withstand voltage test after breaking a large current and a small current was performed. In the measurement, AC100V, 300
The arc is turned on at A, and the minimum impulse withstand voltage at the electrode gap of 2.5 mm is measured. This small current interruption 10 times and withstand voltage measurement were repeated 10 times, and the withstand voltage characteristics after interruption of the large current and small current were determined.

[0071]

[Table 2]

Table 2 shows the results of the blocking and withstand voltage tests. The characteristics are shown as characteristic reference values of sample A (assumed to be 1.0). Samples H, I, J, and K have 1.5 times the cutoff and withstand voltage of Sample A. From these results, the particle diameters of the copper powder, chromium powder and niobium powder were all 53 to 32 μm, 3
It is preferably 2 to 22 μm and 22 μm or less. However, if the particle size is 22 μm or less, there are problems in terms of moldability, productivity, and cost. Therefore, 53 to 22 μm is particularly preferable.

(Embodiment 3) FIG. 7 shows the same result as described above using a powder obtained by pulverizing Cr powder or a mixed powder thereof with V, Nb or W powder in the same manner as in Embodiment 1, and classifying the powder under 22 μm. Similarly, the shape shown in FIG. 4 was finally obtained by infiltration. Further, a plan view of a spiral type electrode in this embodiment and FIG. 8 are sectional views thereof. As shown in these figures, the electrodes are further provided with arc running surfaces 5B, 5C, and 5D integrally with each other by cutting so as to serve as a contact surface with a perfect circular concave portion 5A at the center of the electrode. Between the surfaces 5B, 5C, and 5D, the arc running surface 5 extends from the concave portion 5A.
Three slit grooves 13A to 13C are spirally cut into the arc electrode 1 and the arc electrode supporting portion before the outer peripheral end 5E of B, 5C, 5D. The groove of this spiral structure is 3
Although it is a book, it may be four or five, and may be a curve or a straight line. It is preferable that the diameter of the perfect circular recess 5A is substantially the same as the diameter of the back conductor 4.

The plurality of slit grooves 13A to 13C extend from the concave arc running surface 5A to the electrode side surface from the outer peripheral end 13E of the slit groove. A plurality of arc running surfaces 5A to 5C are formed between each slit groove. The connecting portion 14 straddles the slit grooves 13A to 13C between the outer peripheral end portion 13E and the arc running surface 5E at the outer peripheral end of the electrode. In other words, it acts as a bridge. The connecting portion 14 is formed integrally with the two arc running surfaces 5B to 5D and has the same resistance as the two arc running surfaces 5A to 5C.

For this reason, the heat generated when the arc A flows between each arc running surface and the connecting portion 14 is small, and the current capacity of the electrode can be improved. When the connecting portion 14 is formed integrally with the two arc running surfaces 5B to 5D, the surfaces of the connecting portion 14 and the two arc running surfaces 5B to 5D can be made equal in height, so that the axial direction is reduced as compared with FIG. Not only can the electric field be concentrated, but also the electric field can be reduced, so that the breaking current capacity can be further improved.

When the current path of the current i ₁ flowing through the one-side arc running surface 5B, for example, is longer than the current path of the divided current i ₂ flowing through the other arc running surface 5D, the one-side arc running surface 5B From the other side arc running surface 5
The current is controlled by adjusting the connection portion 14 so that the current i ₁ flows through D. For example, a width L between the outer diameter and the inner diameter of the connecting portion 14 is set. Specifically, the relationship of D ₂ / D ₁ of the outer diameter D ₁ and the inner diameter D ₂ of the contact portion 14 is more than 0.9, to set the width L dimension below 1. In addition, the connecting portion 14 is configured such that the current path of the current i ₁ flowing through the _one- sided arc running surface 5D, for example, is the shunt current i ₂ flowing through the other-side arc running surface 5D
Is provided so as to be longer than the current path.

By arranging the fixed electrode and the movable electrode in correspondence with each other as shown in FIGS.
By controlling the _first path, a reciprocating electric path can be formed substantially in the circumferential direction. The magnetic field H generated when the current i ₁ flows in this path, the arc A generated between the electrodes is driven in the circumferential direction of the electrode, moves on the arc running face. For example, when moving on the arc traveling surface 5B and reaching the boundary with the arc traveling surface 5D, the arc A should pass through the connecting portion 14 and move to the arc traveling surface 5D. The current i ₁ flows as a so-called shunt current i ₂ shunted through the slit groove 13A. Shunt current i ₂ is a function of current i ₁ of the arc running face 5B is prevented from flowing into the arc running face 5D, the arc 21 stagnates in the vicinity of contact portion 14, localized heating of the electrodes, becomes local melting, blocked The present inventors have noticed that disability may occur.

Therefore, the present inventors have adjusted the cross-sectional area, for example, the width and the thickness of the connecting portion 14 so that the current i ₁ and the shunt current i
_The above-mentioned problem was solved by controlling the flow of ₂ through the communication unit 14. That is, the relationship of D ₂ / D ₁ between the outer diameter D ₁ and the inner diameter D ₂ of the connecting portion 14 is set to a width L exceeding 0.9 and less than 1. As a result, the arc A is driven in the circumferential direction of the electrode, magnetically drives the arc running surface,
The breaking current capacity can be significantly increased. For example, if the breaking current capacity of the conventional electrode in which the width L of the connecting portion 10 is not adjusted is set to 1, the breaking current capacity of the electrode of the present invention can be set to 2. This minute,
The electrode of the present invention can be made smaller and lighter than the conventional electrode.

The reason for this is that the width L of the connecting portion 14 is set to be equal to 0.
Becomes 9 or less, the width is widened, flow number shunt current i ₂ is than the current i _1, stagnant current i ₁ is in the vicinity of contact portion 14, resulting in non blocking. If the width of the connecting portion 14 becomes 1 or more, the width of the connecting portion 14 becomes narrower, contrary to the above, the current i ₁ flows too much through the connecting portion 14, the magnetic field H becomes strong, and the arc A becomes electromagnetic force. F causes the electrode to jump out of the electrode and collide with the shield 10, and cannot be used as a circuit breaker. Therefore, D ₂ / D of the outer diameter dimension D ₁ and the inner diameter dimension D ₂ is obtained.
_When the relationship 1 is set to a width L dimension exceeding 0.9 and less than 1, the current i ₁ and the shunt current i ₂ flowing to the connecting portion 14 can be appropriately controlled. In this case, the shunt current i
Controlling ₂ has the advantage that the weight of the electrode can be reduced because the width of the connecting portion 14 can be made narrower than the current i ₁ .
As a result, the above effects can be achieved. This means that only by adjusting the width L, it is possible to arbitrarily design the electrode size and weight according to the increase / decrease of the breaking current capacity and the increase / decrease of the breaking current capacity. It is more preferable to adjust the connecting portion 14 by adjusting the width L and the following thickness. When adjusting the width L of the communication portion 14, the operator can make fine adjustments while watching the width L of the communication portion 14, so that the adjustment work is easy and the work efficiency is good.

The composition of the molded article of this embodiment is No. 1:50 Cr
-47.5Cu-2Nb-0.5Pb, No.2: 50Cr
-47Cu-2Nb-1Pb and No.3: 50Cr-4
6.5Cu-2Nb-1.5Pb.

When the Pb distribution of the arc electrode material after infiltration is 1% and 1.5% Pb, the Pb distribution of the arc electrode material has a gradient, and a stable arc electrode material cannot be supplied. On the other hand, the 0.5% Pb-added material was almost uniformly distributed in the arc electrode material.

As described above, according to the method of the present invention, the material containing 0.5% of Pb can be distributed almost uniformly in the arc electrode material, and a stable arc electrode material can be supplied.

Further, Bi, Te and Sb were examined in the same manner, and the results were the same as the distribution results of Pb.

On the other hand, in order to obtain a sound and desired ingot size, it is important to control the cooling rate of the ingot.
It is necessary to make the cooling rate at the upper part of the ingot higher than that at the side of the ingot. As a second condition for achieving the present invention,
Ceramic particles which have a large specific heat, such as alumina (Al ₂ O ₃ ), and do not react with the molten Cu are suitable as a heat retaining agent for increasing the cooling rate of the upper part of the ingot. If the ceramic particle size at this time is too large or too small, the molten metal flows out between the ceramic particles and does not serve as a mold. The optimal particle size is between 20 mesh and 325 mesh. Also, the required amount of ceramic particles to keep warm is
The thickness is required to be 2/3 or more of the diameter size of the target ingot.

Table 3 shows the results of analyzing the amount of Cr in the ingot when the infiltration temperature was variously changed for the infiltrated steel of various compositions and the results of the porous sintered body and the arc electrode supporting member. It is the result of analyzing each composition element in the ingot when each composition was changed. In addition,
The molten Cu supply and the feeder 8 have the same composition.

No. 1 to No. 3 correspond to the composition C of the porous sintered body.
changing the infiltration temperature when infiltrating pure Cu into r-5Cu material,
This is the amount of Cr in the ingot when held for 120 minutes. It can be seen that the ingot composition at an infiltration temperature of 1250 ° C. is a Cu alloy containing 1.65% Cr.

In Nos. 4, 5, 9, 10, 11, and 13, the composition of the porous sintered body was constant at Cr-5Cu, and the composition of the infiltrant was Cu-Ag, Cu-Zr, and Cu-Si, respectively. , C
It is an elemental analysis result in an ingot when a u-Be alloy is used. It can be seen that each ingot becomes a ternary Cu alloy containing about 0.6% Cr.

Nos. 6, 7, 8, and 12 use pure Cu as the infiltration material.
It is an elemental analysis result in the ingot when V, Nb, V, Nb, and W are added to Cr-5Cu with the composition of the porous sintered body kept constant. Each ingot has a V, Nb, W content of 0.02% or less and an ingot composition of about 1.0% Cr.
It can be seen that this is a Cu alloy containing

[0089]

[Table 3]

The electrical resistance and strength of the ingots obtained in Nos. 1 to 13 were measured using a four-point resistance measurement method, and the strength was measured using an arm-slur tensile tester.

The strength of the interface brazed by the conventional method varies greatly from 22 to 12 kg / mm ^2, and the strength is 12 kg / mm ^2.
Defective brazing was confirmed on the test piece of mm ² . Also,
The electric resistance including the interface is 4.82 μΩ · cm, which is about 3 to 4 times higher than the pure copper material (Comparative Example 2). On the other hand, the interface strength of No. 11 showed a stable strength of 24 to 25 kg / mm ^2, and no defect of the test piece was observed.
Further, in the embodiment of the present invention, the electric resistance including the interface cannot be measured. No. 1's counterpart material is about 0.1% Cr.
Despite being a Cu alloy containing 62%, since there is no interface, the specific resistance is a low value of 1.95 μΩ · cm. This indicates that the resistance value at the interface of the brazing joint in the prior art is very large.

On the other hand, the strength of pure Cu has a maximum value of 22 to 23 kg.
/ Mm ² to 0.2% proof stress is very weak and 4～5Kg / mm ^2, over time modification can not withstand the impact load in the case of the use in the arc electrode support member or other member But Cr or Ag, V, Nb, Zr,
N made of Cu alloy containing Si, W and Be respectively
The electrical resistance values of o.2 to 13 showed about 1.5 to 2.0 times the resistance value as compared with the annealed pure Cu, but about half or less as compared with the conventional brazing joint interface resistance value. Therefore, it can be sufficiently used as an electrode material for an actual vacuum circuit breaker. In addition, each of these strengths has a maximum strength of 22 to 25 kg / mm ² and a pure C
not much different from u, but 10% at 0.2% proof stress
Up to 14 kg / mm ^{2, which} is twice as strong.

When the infiltration temperature is 1150 ° C., it is 0.55 to 0.7.
5%, 0.9-1.0% at 1200 ° C., and 1.6-1.7% at 1250 ° C., so that the amount of solid solution of Cr increases.

As described above, according to the present invention, Cr or A
Since the Cu alloy arc electrode supporting member containing g, V, Nb, Zr, Si, W, and Be, the back conductor, and the external conductor connection portion are not deformed due to repeated impact loads when the electrode is opened and closed. The welding failure due to the deformation is prevented, and the reliability and safety are improved.

Examination of the relationship between the content of alloying elements in Cu and the 0.2% proof stress shows that the inclusion of 0.6% Cr results in 9 k
A yield strength of g / mm ² is obtained, increasing linearly to 11.5 kg / mm ² at 1.6%. And, by containing other alloying elements in addition to Cr, it is strengthened by increasing the amount thereof.
As the content of each element, 0.1% of Ag, 0.1% of Zr,
0.1%, Be 0.05%, Nb, V, and W are each 0.01.
%, A proof stress of 10 kg / mm ² or more can be obtained.

When examining the relationship between the 0.2% proof stress and the specific resistance, the increase in the total solid solution in Cu increases the strength as well as the specific resistance. Therefore, the increase in specific resistance is reduced to improve the strength. It can be seen that this can be achieved by adding another element than Cr alone. In particular, other than Si, the specific resistance is small and high strength can be obtained. In particular, a 0.2% proof stress of 10 kg / mm ² or more and a specific resistance of 1.9 to 2.8 μΩ · cm are preferable.

Cr, Si, Be, Zr, Ag, Nb, V
Examining the relationship between the specific resistance and the W amount, the specific resistance is determined by changing the alloy element to Cr + 3.4Si + 3.5Be + 1.2Zr + 0.6.
By adding Ag + 15 (Nb + V + W) at a ratio of 0.57, the content is multiplied by 0.57 and increased according to the added value of 1.61, but the electrode support portion and other specific resistances are minimized during energization. Since the electrode temperature can be kept low and the arc heat accompanying the arc generation at the time of interruption needs to be cooled through the electrode rod, the heat conductivity needs to be high, so that the heat conductivity can be kept high. In the present embodiment, the desired specific resistance can be roughly determined from the figure. C
When r is used as an arc electrode, the content of each element is set to 0.5% for Si, 0.5% for Be,
r1.5%, Ag 2.5%, Nb, V and W are each 0.1%.
Is preferably contained as an upper limit. The specific resistance is preferably 3.0 μΩcm or less.

Example 4 C having a particle size of 125 to 149 μm
u powder and C in which 98% by weight or more has a particle size of 5 to 22 μm.
r powder, Pb powder having a particle size of 125 to 149 μm,
0 wt% Cu-50 wt% Cr, 49.5 wt% Cu-
50 wt% Cr-0.5 wt% Pb, 48 wt% Cu-
50% by weight Cr-2% by weight Pb, 45% by weight Cu-50
Powders of four different compositions of 5% by weight of Cr-5% by weight of Pb were mixed, loaded into a ball mill, deaerated to 1 × 10 ⁻⁴ Torr, replaced with Ar, and stirred and mixed in an Ar atmosphere for 200 hours.

The obtained mixed powder was mixed with 1 × in the same manner as in Example 1.
After degassing to 10 ^-2 Torr, a pressure of 80 kg / cm ² was applied and 380
Electric current was applied at 0 A for 5 minutes to perform sintering.

Example 5 C having a particle size of 125 to 149 μm
u powder 40% by weight and 98% by weight or more have a particle size of 5 to 22μ.
After mixing 60% by weight of Cr powder as m, the mixture was charged into a ball mill, degassed to 1 × 10 ⁻⁴ Torr, replaced with Ar, and stirred and mixed in an Ar atmosphere for 200 hours. The obtained mixed powder was packed in a mold and molded with a hydraulic press at a pressure of about 3 ton / cm ^{2 to} obtain a molded body having a diameter of 60 mm and a thickness of 10 mm. At this time, the porosity of the molded body was 23 to 28 from the measurement of the bulk density.
%. On the other hand, only Cu powder having a particle size of 44 μm to 150 μm is press-formed at a pressure of about 2.5 ton / cm ² ,
A molded article having a diameter of 50 mm and a thickness of 50 mm was obtained. At this time, the porosity of the molded body is 22 to 27%. The alloy powder compact and the Cu powder compact formed in this manner were placed in close contact with each other in a mild steel capsule, vacuum sealed, and then subjected to hot isostatic sintering (HIP). The conditions of the mild steel capsule, vacuum sealing, HIP processing and the like are as follows. Using a mild steel capsule having a meat pressure of 3 mm, the capsule was heated to about 500 to 600 ° C., degassed to a degree of vacuum of 5 × 10 ⁻⁵ Torr or less while performing evacuation and degassing, and then vacuum sealed. The heating rate is about 10 ° C / min,
The sintering was performed at a sintering pressure of 2000 kg / cm ² and a sintering temperature of 1000 ° C. for 2 hours. The true density of the electrode material after the HIP treatment was 99%.

(Embodiment 6) Table 4 shows the specifications of the vacuum valve at various ratings. The electrode in this embodiment has the same composition and structure as those in Embodiments 1 to 5.

FIG. 9 is a cross-sectional view of the No. 1 vacuum valve shown in Table 4, and FIG. 10 is a cross-sectional view of the No. 4 vacuum valve.

[0103]

[Table 4]

The upper and lower seal rings 38a and 38b are integrally formed at the upper and lower openings of the insulating cylinder 35 made of insulating material.
Are provided to form a vacuum chamber, a fixed electrode 30a is vertically provided in the middle of the seal ring 38a, and the seal ring 38 located immediately below the fixed electrode 30a is formed.
A movable electrode rod 34 forming a part of the movable electrode 30b is provided in the middle of the movable electrode 30b so as to be movable up and down, and the arc electrode 31b of the movable electrode 30b is brought into contact with and separated from the arc electrode 31a of the fixed electrode 30a. A metal bellows 37 is provided inside the seal ring 38b located around the movable-side electrode rod 34 so as to extend and contract, and is further provided with a cylindrical shape around both of the arc electrodes. A sealing member 36 made of a metal plate is provided by a vacuum container of the insulating cylinder 35, and the sealing member 36 is configured so as not to impair the insulation of the vacuum container of the insulating cylinder 35.

Further, the arc electrodes 31a and 31b are connected to the arc electrode support portions 32a and 32a obtained by the above-described infiltration.
32b, and external conductor connecting portions 33a, 3
3b and the back conductors 39a and 39b. A glass or ceramic sintered body is used for the vacuum container formed of the insulating cylinder 35. The vacuum container formed of the insulating cylinder 35 is brazed to the seal rings 38a and 38b through an alloy plate having a thermal expansion coefficient of glass or ceramics such as Kovar, and is maintained at a high vacuum of 10 ^-6 mmHg or less.

In any of the electrodes, screws 45a and 45b are provided at the external conductor connection portions, and are connected to external terminals to serve as current paths. An exhaust pipe (not shown) is provided on the seal ring 38a, and is connected to a vacuum pump for exhaust. The getter is provided to absorb a small amount of gas generated inside the vacuum vessel and maintain the vacuum. The sealing member 36 has a function of adhering and cooling metal vapor on the surface of the main electrode generated by the arc, and the adhered metal has a function of maintaining a degree of vacuum having a getter function.

In the figures, 43 is the outer diameter of the insulating cylinder, 44 is its length, 41 is the diameter of the conductor behind the electrode, 40 is the diameter of the electrode body, and 42 is the thickness of the electrode. 46 is a guide, and 47 is a button. The button 47 is a recess formed of a perfect circle having a desired depth, and is the same as the recess 5A shown in FIG.

As shown in Table 4, the vacuum valve according to the present invention has an outer diameter, a length, a diameter of a back conductor, a diameter, a thickness, a recess diameter, and a recess of an insulating tube depending on a difference in rated breaking capacity. The depth, the number of spiral grooves and the spiral are different.

FIG. 11 is a graph showing the relationship between the effective value (y) of the cut-off voltage and current and the outer diameter (x) of the insulating cylinder. The effective value of the interruption voltage / current is obtained by multiplying the interruption voltage (kV) by the effective value of the interruption current (kA). As shown in FIG. 11, the effective values (y) of the cut-off voltage and current are 11.25x-525 and 5.35x-2.
It is preferable to set the outer diameter of the insulating cylinder with respect to the effective value of the cut-off voltage and current so as to fall between the values obtained with 41.5.

FIG. 12 is a graph showing the relationship between the diameter (mm) of the arc electrode and the effective value of the cut-off voltage / current (× 10 ³ kVA). It is preferable that the arc electrode diameter (y) be set to a value obtained from 0.15x + 22 and 0.077x + 20 with respect to the cutoff voltage / current effective value (x).

FIG. 13 is a diagram showing the relationship between the outer diameter (y) of the insulating cylinder and the diameter (x) of the arc electrode. Outer diameter of insulation tube (y)
Is preferably set to a value between 1.26x + 10 and 1.26x + 30. In this embodiment, y
= 1.26x + 19.6.

FIG. 14 is a diagram showing the relationship between the diameter (y) of the arc electrode and the diameter (x) of the concave portion or the diameter (x) of the conductor behind the electrode. Arc electrode diameter (y) is 2.4x + 6.4 and 2.32
x-3.0.

Table 5 shows the results of a performance test (element test with an electrode diameter of 20 mm) made of the infiltration integrated structure shown in FIG. 4 as various electrode materials. The electrode structure in this performance test was obtained by forming a button at the center of the electrode in FIG. Although the withstand voltage characteristic decreases when the Cr content is low, a high cut-off current effective value as the cut-off performance can be obtained. And by adding Nb, P
It is clear that the inclusion of b makes it possible to obtain high both. Therefore, it is clear that higher performance can be obtained by providing the spiral groove as in the present invention. The spiral grooves are provided regularly at regular intervals.

[0114]

[Table 5]

FIG. 15 is a configuration diagram of a vacuum circuit breaker showing a vacuum valve 59 according to the present invention and its operating device.

This is a small and lightweight structure in which the operating mechanism is disposed on the front side, and three sets of three-phase epoxy resin cylinders 60 having tracking resistance, which support a vacuum valve, are disposed on the rear side.

Each phase end is of a horizontal draw-out type supported horizontally by an epoxy resin cylinder and a vacuum valve support plate. The vacuum valve is opened and closed by an operating mechanism via an insulating operating rod 61.

The operating mechanism is a simple, compact, lightweight electromagnetically operated mechanical tripping free mechanism. Shock is small because the opening and closing stroke is small and the mass of the movable part is small. On the front face of the main body, in addition to a manually connected secondary terminal, an open / close indicator, an operation counter, a manual trip button, a manual input device, a pull-out device, an interlock lever, and the like are arranged.

(A) Closed state This indicates the closed state of the circuit breaker, and current flows through the upper terminal 62, the main electrode 30, the current collector 63, and the lower terminal 64. The contact force between the main electrodes is determined by the contact spring 6 mounted on the insulating operation rod 61.
5 is kept.

The electromagnetic force due to the contact force of the main electrode, the force of the pre-cut spring, and the short-circuit current is applied to the support lever 66 and the prop 6
7 is held. When the closing coil is excited, the plunger 68 pushes up the roller 70 via the knocking rod 69 from the open state, turns the main lever 71 to close the contact, and holds it with the support lever 66.

(B) Tripping free state The movable main electrode is moved downward by the separating operation, and an arc is generated from the moment when the fixed and movable main electrodes are separated. The arc is extinguished in a short time due to the high dielectric strength in a vacuum and the vigorous diffusion action.

When the tripping coil 72 is excited, the tripping lever 73 disengages the prop 67 and the main lever 71
Is turned by the force of the quick-release spring to open the main electrode. This operation is a mechanical trip-free operation that is performed irrespective of the presence or absence of a closing operation.

(C) Open circuit state After the main electrode is opened, the link is restored by the reset spring 74, and at the same time, the prop 67 is engaged. When the closing coil 75 is excited in this state, the closed state shown in FIG. 76 is an exhaust pipe.

The vacuum circuit breaker cuts off the arc in a high vacuum and has excellent breaking performance due to the high dielectric strength of the vacuum and the high-speed diffusion of the arc. When the switch is opened and closed, the current is cut off before reaching the zero point, so that a so-called cut-off current is generated, and a switching surge voltage proportional to the product of this current and the surge impedance may be generated. For this reason, 3kV transformers and 3k
When a V, 6 kV rotating machine or the like is directly opened and closed by a vacuum circuit breaker, it is necessary to connect a surge absorber to a circuit to suppress a surge voltage and protect the equipment. As the surge absorber, a capacitor is used as a standard, but a ZnO nonlinear resistor can be used depending on the withstand voltage of the shock wave of the load.

According to the above embodiment, it is possible to cut off at 7.2 kV and 31.5 kA at a pressure of 150 kg and a cutoff speed of 0.93 m / sec.

FIG. 16 shows the internal structure of the vacuum switchgear two-stage switchgear of this embodiment. 91 is an upper breaker compartment, 92 is a metal clad frame compartment, 93 is a lower breaker compartment,
94 is a busbar compartment, 95 is a current transformer, 96 is a connection conductor, 97 is a cable compartment, 98 is a control lead-in cable section, and 99 is a surge absorber. Since the power supply of the vacuum circuit breaker has three phases, three vacuum circuit breakers are provided for one power supply at a depth with respect to the paper surface.

(Embodiment 7) FIG. 17 is a diagram showing a main circuit configuration for interrupting a DC circuit by using the same vacuum valve as in Embodiment 6. 80 is a DC power supply, 81 is a DC load, 82 is a vacuum valve, 83 is a short ring, 84 is an electromagnetic repulsion coil, 85 is a commutation capacitor, 86 is a commutation reactor, 8
7 is a trigger gap, 88 is a static overcurrent trip device,
Reference numeral 89 denotes a ZnO nonlinear resistor.

In this embodiment, the following features are obtained.

(1) Since no air arc is generated at the time of interruption, no noise is generated and the disaster prevention effect is large.

(2) Since the opening time is short (about 1 ms), it is possible to cut off the fault current having a rush rate exceeding the standard value, and it is possible to keep the current limiting value small.

(3) The use of a vacuum valve makes it possible to cut off high-frequency capacitor discharge current, extremely short arc time (about 0.5 ms), and reduce contact wear.

(4) The current scale can be set with high accuracy by employing a static overcurrent trip device, and there is no aging.

(5) The use of a latch-type electric spring actuator significantly reduces the operating current and eliminates the need for a holding current.

(6) The occupied area is reduced to about 1/4, and the substation space can be reduced.

[0135]

According to the present invention, in a vacuum circuit breaker having both a fixed-side electrode and a movable-side electrode having an arc electrode, a support member for supporting the arc electrode, and a coil electrode connected to the support member, crystal grains are provided. The fine metal mixed powder, which is mechanically pulverized and mixed so as to have a diameter of 53 μm or less, is sintered by using any one of discharge sintering, hot pressing, and HIP to obtain a highly conductive metal, Crystal grains become fine for all of solitary metals, voltage-resistant metals and welding-resistant metals,
A high-performance electrode member having good initial performance is obtained, and the arc electrode, the arc electrode support member, the coil electrode material,
Preferably, the conductive rod has a metallographically integral structure by non-bonding sintering or friction pressure bonding processing, and since the brazing of the support member and the coil electrode becomes unnecessary, the arc electrode support member and the coil electrode By improving the strength of the material, it is possible to prevent welding failure due to electrode deformation, so
A highly safe vacuum circuit breaker can be obtained.

According to the present invention, in a vacuum circuit breaker provided with a fixed-side electrode and a movable-side electrode having an arc electrode and a support member for supporting the arc electrode, a vacuum circuit breaker provided with the arc electrode and the arc electrode support member and thereafter. It has an integral structure with a highly conductive metal by non-bonding melting or solid phase diffusion bonding. Preferably, the support member and the subsequent members are integrated by melting, and are made of a Cu alloy containing 0.01 to 2.5% by weight of Cr, Ag, V, Nb, Zr, Si, W, Be and the like. It is preferable to reduce the machining process and assembling process of each member due to brazing, prevent the destruction and falling off of the electrode material due to poor brazing, and improve the strength, as well as the welding failure due to electrode deformation. Can be prevented. Further, since a low melting point metal such as Pb is contained in the arc electrode and welding can be prevented, a smaller, highly reliable and safe vacuum circuit breaker, and a vacuum valve and an electric contact used therefor can be obtained.

[Brief description of the drawings]

FIG. 1 is a graph showing the yield of mechanically pulverized fine metal powder (particle size: 53 μm or less) of an example.

FIG. 2 is a cross-sectional view illustrating a method for manufacturing an electrode member for a vacuum circuit breaker according to the present invention.

FIG. 3 is a sectional view of an electrode after melting according to the present invention.

FIG. 4 is a cross-sectional view of an electrode after cutting according to the present invention.

FIG. 5 is a comparison diagram of the thickness reduction of the arc electrode portion after the electrode member is manufactured.

FIG. 6 is a sectional view of a vacuum valve.

FIG. 7 is a plan view of an electrode having a spiral groove according to the present invention.

FIG. 8 is a sectional view of an electrode having a spiral groove according to the present invention.

FIG. 9 is a sectional view of a vacuum valve.

FIG. 10 is a sectional view of a vacuum valve.

FIG. 11 is a diagram showing a relationship between an effective value of a cutoff voltage and current and an outer diameter of an insulating cylinder.

FIG. 12 is a diagram showing a relationship between an arc electrode diameter and an effective value of a breaking voltage and current.

FIG. 13 is a diagram showing the relationship between the outer diameter of the insulating cylinder and the diameter of the arc electrode.

FIG. 14 is a diagram showing the relationship between the diameter of an arc electrode and the diameter of a concave portion or the diameter of an electrode back conductor.

FIG. 15 is an overall configuration diagram of a vacuum circuit breaker.

FIG. 16 is a configuration diagram of a vacuum circuit breaker two-stage switchgear.

FIG. 17 is a circuit diagram using a DC vacuum circuit breaker.

[Explanation of symbols]

1, 31a, 31b: arc electrode, 2: arc electrode support, 3, 33a, 33b: external conductor connection, 4, 39a,
39b: back conductor, 5A, 5B, 5C, 5D, 5E: arc running surface, 13A, 13B, 13C: slit groove, 14
... Connecting part, L ... Width, 21, 30a ... Fixed electrode, 23,3
0b: movable electrode, 24, 34: electrode rod, 28, 35: insulating cylinder, 36: sealing member, 26, 37: bellows, 2
7, 38a, 38b: seal ring, 60: epoxy resin cylinder, 61: insulating operation rod, 62: upper terminal, 63
... current collector, 64 ... lower terminal, 65 ... contact spring, 66 ... support lever, 68 ... plunger, 71 ... main lever, 72 ...
Trip coil, 75: closing coil, 76: exhaust cylinder, 80
... DC power supply, 81 ... DC load, 82 ... Vacuum valve, 83
... Short ring, 84 ... Electromagnetic repulsion coil, 85 ... Commutation capacitor, 86 ... Commutation reactor, 87 ... Trigger gap, 88 ... Stationary overcurrent trip device, 89 ... ZnO nonlinear resistor.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Toru Tanimizu 1-1-1, Kokubuncho, Hitachi City, Ibaraki Prefecture Inside the Hitachi, Ltd. Kokubu Plant (72) Inventor Yoshimi Hakamada 1-1, Kokubuncho, Hitachi City, Ibaraki Prefecture No. 1 Inside the Kokubu Plant of Hitachi, Ltd.

Claims (15)

[Claims] 1. A vacuum valve having a fixed side electrode and a movable side electrode in an insulating container, and a conductor connected to each of the fixed side electrode and the movable side electrode inside the vacuum valve outside the vacuum valve. A terminal, and opening and closing means for driving the movable side electrode via an insulating rod connected to the movable side electrode, wherein the fixed side electrode and the movable side electrode support an arc electrode member and the arc electrode. In a vacuum circuit breaker provided with a support member, the arc electrode member has a highly conductive metal and a refractory metal having a higher melting point than the highly conductive metal, and the refractory metal has a particle size of 5 to 6 μm. A vacuum circuit breaker characterized in that the content is 70% by weight or more. 2. A vacuum valve having a fixed side electrode and a movable side electrode in an insulating container, and a conductor connected to each of the fixed side electrode and the movable side electrode inside the vacuum valve outside the vacuum valve. A terminal, and opening and closing means for driving the movable side electrode via an insulating rod connected to the movable side electrode, wherein the fixed side electrode and the movable side electrode support an arc electrode member and the arc electrode. In a vacuum circuit breaker provided with a supporting member and a coil electrode member connected to the supporting member or the arc electrode member and an energizing electrode rod, the arc electrode member has a higher melting point in the highly conductive metal than the highly conductive metal. It is made of a sintered alloy in which refractory metal particles are dispersed or an infiltration alloy in which the highly conductive metal is infiltrated into the refractory metal, wherein the refractory metal has a particle size of 5 to 60 μm in an amount of 70% by volume or more. Yes, the arc The electrode member and the arc electrode support member, the arc electrode member and the arc electrode support member and the coil electrode member, or the arc electrode member and the current-carrying electrode rod are integrally formed by sintering or infiltration. And a vacuum circuit breaker. 3. A vacuum valve having a fixed side electrode and a movable side electrode in an insulating container, and a conductor connected to each of the fixed side electrode and the movable side electrode inside the vacuum valve outside the vacuum valve. A terminal, and opening and closing means for driving the movable side electrode via an insulating rod connected to the movable side electrode, wherein the fixed side electrode and the movable side electrode support an arc electrode member and the arc electrode. In the method of manufacturing a vacuum circuit breaker provided with a support member, the arc electrode member has a highly conductive metal and a refractory metal having a higher melting point than the highly conductive metal,
A mixed powder is prepared by classifying a powder having a particle size of 5 to 60 μm of the refractory metal to 70% by weight or more, and then using the mixed powder, sintering or infiltrating the refractory metal with the highly conductive metal. A method for manufacturing a vacuum circuit breaker. 4. A vacuum valve having a fixed side electrode and a movable side electrode in an insulating container, and a conductor connected to each of the fixed side electrode and the movable side electrode inside the vacuum valve outside the vacuum valve. In a method for manufacturing a vacuum circuit breaker comprising a terminal and opening / closing means for driving the movable electrode through an insulating rod connected to the movable electrode, the fixed electrode and the movable electrode are an arc electrode member. Having an arc electrode support member or an arc electrode member and a conducting electrode rod made of a highly conductive metal supporting the arc electrode member, wherein the arc electrode member has the highly conductive metal and a refractory metal. Manufactured by sintering or infiltrating the refractory metal with the highly conductive metal using a mixed powder obtained by classifying a powder having a particle size of 5 to 60 μm of the refractory metal to 70% by weight or more;
The method for manufacturing a vacuum circuit breaker, wherein the arc electrode member and the arc electrode support portion or the current-carrying electrode bar are integrally formed by the sintering or friction welding. 5. A vacuum valve having a fixed side electrode and a movable side electrode in an insulating container maintained in a high vacuum, wherein both electrodes are arc electrodes made of a composite member of a refractory metal and a highly conductive metal. A member, and an arc electrode support member or a current-carrying electrode rod made of a highly conductive metal that supports the arc electrode member, wherein the arc electrode member has a high conductivity metal and a refractory metal having a higher melting point than the highly conductive metal. 7 comprising a sintered alloy with a refractory metal or an infiltration alloy in which the highly conductive metal is infiltrated into the refractory metal, wherein the refractory metal has a particle size of 5 to 60 μm.
0% by weight or more, and the arc electrode and the arc electrode supporting member or the current-carrying electrode member are integrally formed by sintering or melting. 6. A sintered alloy of a refractory metal having a particle size of 5 to 60 μm and 70% by weight or more and a highly conductive metal or an infiltration in which the highly conductive metal is infiltrated into the refractory metal. An electric contact, wherein an arc electrode member made of an alloy and an arc electrode support member or a current-carrying electrode rod made of a highly conductive metal supporting the arc electrode member are integrally formed by sintering or infiltration. . 7. A vacuum valve provided with a fixed electrode and a movable electrode in an insulating container, and a conductor connected to each of the fixed electrode and the movable electrode in the vacuum valve outside the vacuum valve. A vacuum circuit breaker comprising a terminal and opening / closing means for driving the movable-side electrode via an insulating rod connected to the movable-side electrode, wherein the fixed-side electrode and the movable-side electrode have a particle size of 5 to 60 μm. Electrode made of an alloy containing refractory metal particles having a volume ratio of 70% by volume or more and a highly conductive metal, an electrode support made of a highly conductive metal supporting the arc electrode, and a smaller diameter than the electrode support The arc electrode and the electrode support, the back conductor, and the external conductor connection are integrally formed of the highly conductive metal. Vacuum cut-off characterized by . 8. A vacuum valve having a fixed side electrode and a movable side electrode in an insulating container, and a conductor connected outside of the vacuum valve to each of the fixed side electrode and the movable side electrode in the vacuum valve. A vacuum circuit breaker comprising a terminal and opening / closing means for driving the movable-side electrode via an insulating rod connected to the movable-side electrode, wherein the fixed-side electrode and the movable-side electrode have a particle size of 5 to 60 μm. Has an arc electrode made of an alloy containing refractory metal particles having a volume ratio of 70% by volume or more and a highly conductive metal, and an electrode support portion made of a highly conductive metal for supporting the arc electrode. The electrode support is formed integrally with the highly conductive metal, the insulating container is a cylinder, and has a rated voltage (kV) and an effective breaking current (k).
A) multiplied by (A) is the outer diameter x (mm) of the insulating container.
A vacuum circuit breaker characterized by being within a range of values determined by the following equations (1) and (2). y = 11.25x-525 (1) y = 5.35x-242 (2) 9. A vacuum valve having a fixed side electrode and a movable side electrode in an insulating container, and a conductor connected to each of the fixed side electrode and the movable side electrode inside the vacuum valve outside the vacuum valve. A vacuum circuit breaker comprising a terminal and opening / closing means for driving the movable-side electrode via an insulating rod connected to the movable-side electrode, wherein the fixed-side electrode and the movable-side electrode have a particle size of 5 to 60 μm. Has an arc electrode made of an alloy containing refractory metal particles having a volume ratio of 70% by volume or more and a highly conductive metal, and an electrode support portion made of a highly conductive metal for supporting the arc electrode. The electrode support is formed integrally with the highly conductive metal, and the diameter y (mm) of the arc electrode is a value x (kVA × 10 ³ ) obtained by multiplying the rated voltage (kV) by the effective value of the breaking current (kA). ), The following equations (3) and (4) Vacuum circuit breaker characterized by being within the range of values determined by: y = 0.15x + 22 (3) y = 0.0077x + 20 (4) 10. A vacuum valve having a fixed side electrode and a movable side electrode in an insulating container, and a conductor connected to each of the fixed side electrode and the movable side electrode in the air valve outside the vacuum valve. A vacuum circuit breaker comprising a terminal and opening / closing means for driving the movable-side electrode via an insulating rod connected to the movable-side electrode, wherein the fixed-side electrode and the movable-side electrode have a particle size of 5 to 60 μm. Has an arc electrode made of an alloy containing refractory metal particles having a volume ratio of 70% by volume or more and a highly conductive metal, and an electrode support portion made of a highly conductive metal for supporting the arc electrode. The electrode support is formed integrally with the highly conductive metal, the insulating container is a cylinder, and the outer diameter y (mm) of the insulating container is smaller than the diameter x (mm) of the arc electrode by (5) And of the value obtained by equation (6) Vacuum circuit breaker, characterized in that in 囲内. y = 1.26x + 10 (5) y = 1.26x + 30 (6) 11. A vacuum valve having a fixed side electrode and a movable side electrode in an insulating container maintained in a high vacuum, wherein said two electrodes have a particle size of 5 to 60 μm and have a fire resistance of 70% by volume or more. An arc electrode made of a composite member having metal particles and a highly conductive metal, an electrode support made of a highly conductive metal supporting the arc electrode, a back conductor smaller in diameter than the electrode support, and the back conductor A vacuum valve having an outer conductor connection portion having a larger diameter, wherein the arc electrode and the electrode support portion, the back conductor, and the outer conductor connection portion are integrally formed of the highly conductive metal. 12. A vacuum valve having a fixed side electrode and a movable side electrode in an insulating container maintained in a high vacuum, wherein said two electrodes have a particle size of 5 to 60 μm and have a fire resistance of 70% by volume or more. An arc electrode made of a composite member having metal particles and a highly conductive metal, and an electrode support portion made of a highly conductive metal supporting the arc electrode, wherein the arc electrode and the electrode support portion have the high conductivity. Formed integrally with a metal
The insulating container is a cylinder, and a value (y) obtained by multiplying a rated voltage (kV) by an effective value of a breaking current (kA) is smaller than the insulating container outer diameter x (mm) by the following equations (1) and (2). A vacuum valve characterized by being within a range of values determined by an equation. y = 11.25x-525 (1) y = 5.35x-242 (2) 13. A vacuum valve having a fixed side electrode and a movable side electrode in an insulating container maintained in a high vacuum, wherein said two electrodes have a particle size of 5 to 60 μm and have a fire resistance of 70% by volume or more. An arc electrode made of a composite member having metal particles, a highly conductive metal and a low melting point metal, and an electrode support portion made of a highly conductive metal supporting the arc electrode, wherein the arc electrode and the electrode support portion Is integrally formed of the highly conductive metal, and the diameter y (mm) of the arc electrode is a value x obtained by multiplying the rated voltage (kV) by the effective value of the breaking current (kA).
(kVA × 10 ³ ) A vacuum valve having a value within a range determined by the following equations (3) and (4). y = 0.15x + 22 (3) y = 0.0077x + 20 (4) 14. A vacuum valve provided with a fixed side electrode and a movable side electrode in an insulating container maintained in a high vacuum, wherein said two electrodes have a particle size of 5 to 60 μm and have a fire resistance of 70% by volume or more. An arc electrode made of a composite member having metal particles and a highly conductive metal, and an electrode support portion made of a highly conductive metal supporting the arc electrode, wherein the arc electrode and the electrode support portion have the high conductivity. The insulating container is a cylinder, and has an outer diameter y of the insulating container.
(Mm) is within a range of a value obtained from the diameter x (mm) of the arc electrode by the following equations (5) and (6). y = 1.26x + 10 (5) y = 1.26x + 30 (6) 15. An arc electrode made of an alloy containing refractory metal particles having a particle size of 5 to 60 μm of 70% by volume or more, a highly conductive metal and a low melting point metal, and a high conductive material supporting said arc electrode. An electrode support made of a conductive metal, a back conductor having a smaller diameter than the electrode support, and an external conductor connection having a larger diameter than the back conductor. The arc electrode, the electrode support, the back conductor, and the external conductor An electrical contact, wherein the connection part is formed integrally with the highly conductive metal.