JP2000235825A - Electrode member for vacuum circuit-breaker and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the reliability while lowering dispersion of the circuit- breaking performance and the withstand voltage performance by forming an arc electrode member of a high conductive metal and a fire resistant metal having a melting point higher than that of the high conductive metal, and using the high conductive metal and the fire resistant metal having flat particle shape. SOLUTION: An arc electrode 1 is made of the compound alloy obtained by thermally spraying the mixture powder of the high conductive metal and the fire resistant metal, and the arc electrode 1, an electrode support 2, a back conductor 4 and an external conductor connection part 3 are integrally formed with each other by diffusion of the high conductive metal. As an electrode member to be used, the metal powder composed of one or two kinds of Cu, Au, Ag as a high conductive metal, one or two kinds of Cr, W, Mo, Fe as a fire resistant metal and one or more kinds of Nb, V, Ti having effective withstand voltage performance is used. Each metal powder is mixed, and laminated for coating on a rough surface part of a material to be thermally sprayed with the mixture powder, and fine chrome particles are evenly distributed in the matrix of the flat copper particles.

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, and an electric contact used for the same.

[0002]

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

The above-mentioned arc electrode material is directly exposed to an arc in order to open and close a high voltage and a large current. Satisfactory characteristics required for the arc electrode include a large breaking capacity, a high withstand voltage, and a small contact resistance.
(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.

In Japanese Patent Application Laid-Open No. Sho 62-15716, a Fe group element (Fe, N
i, Co, etc.) or their alloy system to a thickness of about 3 μm. As a coating method, production of a contact material for an electrode is described using electroplating, dry plating, plasma spraying, CVD, or sputter deposition. However, if a film with a thickness of about 3 μm is formed on the surface of the electrode material prepared by the infiltration method by the plasma spraying method, the adhesive force with the substrate is weak, and the film may be peeled off by a small impact. is there. Also, the effect is small because the film is extremely thin. Further, the number of manufacturing steps of the electrode material is increased, so that the cost is increased.

[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 formed by infiltrating copper into 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 having weak bonding force, which is a refractory metal, in the composite obtained by melting and impregnating copper, which is a highly conductive metal, into this molded product, are lightly floated and floated up, and melt into the electrode support (copper). The dechroming phenomenon of the 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 and improve the uniform dispersibility of fine chromium particles and the like in a copper matrix constituting an electrode member, so that variations in the breaking performance and withstand voltage performance of a vacuum circuit breaker. It is an object of the present invention to provide a vacuum circuit breaker which can reduce the pressure and improve the reliability of the vacuum circuit breaker, and a vacuum valve and an electric contact used therefor.

[0008]

SUMMARY OF THE INVENTION According to the present invention, there is provided a method of forming a laminate in which a copper layer and a chromium particle are flatly and uniformly dispersed by a plasma spraying method on a copper (arc electrode supporting member). By forming and further performing a vacuum heat treatment, the interface between the composite member (arc electrode) and copper (arc electrode support member) has a flat and strong bonding force. There is no dechromation or thinning of the molded body as seen when copper is infiltrated into the molded body produced by the powder metallurgy method, and electrical characteristics superior to conventional copper alloys can be obtained.

According to the present invention, a powder of a highly conductive metal such as Cu, Ag, Au or the like, and Cr, W, Mo having a particle size of 5 to 100 μm,
And an alloy composed of one or more of refractory metals such as Ta and the like.
70% by weight or more, preferably 80% by weight
The content is more preferably 90% by weight or more.

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 10 to 80% by weight, and a highly conductive metal such as Cu is 20%.
It is desirably about 90% by weight.

The above alloy contains Pb at 10% by weight or less,
b, total 10% by weight of at least one metal of Bi
Hereafter, 10% by weight or less of Ti can be added.

The present invention is characterized in that the highly conductive metal and the refractory metal are formed by flat crystal grains by spraying the metal mixed powder using either plasma spraying or flame spraying. Alternatively, the unevenness at the interface between the arc electrode and the arc electrode support is 100 μm or less.

[0013] The present invention provides a vacuum valve having a fixed side electrode and a movable side electrode in an insulating vacuum vessel, and each of the fixed side electrode and the movable side electrode in the vacuum valve is provided outside the vacuum valve. In the vacuum circuit breaker provided with a conductor terminal connected to the movable side electrode and an opening / closing means for driving the movable side electrode, the fixed side electrode and the movable side electrode are made of the above-mentioned alloy of a refractory metal and a highly conductive metal. A vacuum circuit breaker having an arc electrode. The electrode material is made of a composite alloy of a refractory metal and a highly conductive metal mainly composed of Cu or the like. For the former, a refractory metal having a high melting point of about 1800 ° C. or more, such as Cr, W, Mo, and Ta, is used. And the solid solution amount to Cu is 3
% Or less is preferable.

The refractory metal is 20 to 80% by weight, especially 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.
One or a mixture of two or more of Cu, Ag and Au
A highly conductive metal or a highly conductive alloy mainly composed of these, an alloy with one or more of Pb, Bi, Te and Sb, wherein the electrode supporting portion is formed of the highly conductive metal or alloy. It is desirable to consist of

The electrode support, the back conductor and the external conductor connection are made of Cr, Ag, W, V, Nb, Mo, Ta, Zr,
It is preferable that one or more of Si, Be, Ti, Co, and Fe be made of an alloy of 2.5% by weight or less and Cu, Ag, or Au. The arc electrode according to the present invention is made of a composite alloy obtained by spraying a mixed powder of a highly conductive metal and a refractory metal, and the arc electrode and the electrode support, the back conductor and the external conductor connection are preferably formed of the highly conductive metal. Are preferably formed integrally by the diffusion of

The electrode support in the present invention preferably has a 0.2% proof stress of 10 kg / mm ² or more and a specific resistance of 2.8 μΩcm or less.

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 in contact with each other.

It is preferable that the arc electrode, the electrode support, the back conductor, and the external conductor connection are integrally formed by diffusion bonding of the highly conductive metal.

A plurality of arc electrodes and electrode support parts;
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 end side extending from the center portion side to the outer peripheral side of the electrode according to the present invention include 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 outer periphery of the groove and the outer end of the arc running surface, and the path of the current flowing from both arc running surfaces is one side of the arc running surface on the other side. 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.

According to the present invention, there is provided a vacuum valve provided with a fixed side electrode and a movable side electrode in an insulating container maintained in a high vacuum, wherein both the electrodes have the above-mentioned refractory metal particles, a highly conductive metal, and Preferably, an arc electrode made of a composite member containing a low melting point 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 a back conductor larger than the back conductor. The outer conductor connecting portion having a diameter is formed integrally with the highly conductive metal, and the arc electrode is formed by the above-described thermal spraying.

Further, the present invention provides an arc electrode made of an alloy containing the above-mentioned refractory metal particles, a highly conductive metal and preferably a low melting point metal, and an electrode support made of a highly conductive metal for supporting the arc electrode. And a back conductor having a smaller diameter than the electrode support, and an outer conductor connection having a larger diameter than the back conductor. The arc electrode is connected to the electrode support, the back conductor, and the outer back conductor connection. An electric contact characterized by being formed integrally by thermal spraying.

According to the method of manufacturing an electric contact of the present invention, the arc electrode is formed by spraying a mixed powder of a refractory metal and a highly conductive metal having the above-described particle size on a material to be sprayed to a desired thickness by metal spraying. I do. Thereafter, the metal spray composite alloy is subjected to a heat treatment for diffusion bonding in a vacuum. The heating temperature is 80
It is preferred to heat to 0 to 1000 ° C.

The electrode structure of the vacuum circuit breaker comprises an arc electrode, an arc electrode support member, a back conductor and an outer back conductor joint, and the arc electrode is a composite of a refractory metal having the above-mentioned particle size and a highly conductive metal. Alloy, the former being Cr, W, M
A metal having a high melting point of 1800 ° C. or more, such as o or Ta, is used. As the highly conductive metal, a metal having a small solid solution amount of 3% or less in Cu, Ag, and Au is preferable. Pure Cu is particularly preferable other than the arc electrode supporting member. However, since the strength is low, the members are reinforced with pure iron or stainless steel, which is an iron-based material, to prevent deformation of these members.

According to the present invention, the arc electrode is preferably made of Cr30 by weight.
-60%, Nb 0.5-5.0%, preferably 0.3-3.0.
% And Pb 0.1 to 0.5%.

According to the present invention, the arc electrode and the members other than the arc electrode supporting member are constituted by a monolithically continuous integral 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, the arc electrode supporting member, and the coil electrode material of the external conductor connecting portion constituting the electrode are formed in a monolithically continuous integrated structure, and at the same time, the electrode structure of the integrated structure is manufactured. Highly conductive metals other than the arc electrode supporting member formed in the same process include 0.01 to
2.5% by weight of Cr, W, V, Zr, Si, Mo, T
a, Be, Nb, Ti, one or more of Au, A
g and Cu can be used.
Therefore, the mechanical strength, particularly the proof stress, can be greatly increased without significantly lowering the electrical conductivity of the material other than 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 between 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 members other than the arc electrode supporting member with each other by not joining them together and forming a metallographically continuous integrated structure and increasing the strength of each of the above members. As a result, a highly reliable and safe vacuum circuit breaker in which adverse effects are eliminated can be provided. According to the metal spraying method of the present invention, Cr, W, M
o, Ta powder and Pb, Bi, Te, Sb powder or any other metal particles mixed in a predetermined composition and a metal mixed powder and a block made of Cu, Ag, Au, or an alloy thereof, and the plasma mixed with the metal mixed powder. A metal composite alloy is formed by thermal spraying and flame spraying. Further, the treated metal composite member is subjected to vacuum heat treatment to be alloyed. Thereafter, the metal composite member is processed into an electrode having a predetermined shape.

The present invention resides in an electrode member for a vacuum circuit breaker, wherein the metal mixed powder is sprayed by a metal spraying method to form a metal composite alloy.

In the production of an electrode member for a vacuum circuit breaker, a highly porous mixed metal compact produced by a conventional compacting method has a very weak bonding force between particles, and is difficult to handle. Further, the composite member obtained by melting and impregnating a copper-based or silver-based metal, which is a highly conductive component, into the molded body has a non-uniform composition due to dechromization in which chromium of the molded body dissolves in copper or silver.
Alternatively, phenomena such as wall thinning due to erosion at the interface of the infiltration portion occur, which is not preferable.

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

In the present invention, the highly conductive metal C
one or two of u, Au, Ag, one or two of Cr, W, Mo, Fe as refractory metals, and Nb, V, Ti, Ta, Zr, particles which are effective for withstand voltage. Silicon 1
Metal powder consisting of more than one species. C, which is a highly conductive metal
one or two of u, Au, Ag, one or two of Cr, W, Mo, Fe as refractory metals, and Nb, V, Ti, Ta, Zr, particles which are effective for withstand voltage. Si 1
Or more, Pb, Bi, Sb, T
It is preferable that it is composed of one or more metal powders of e. The metal powder is housed in a glass mixer, and the glass container is rotated for several hours to sufficiently mix the individual metal powders. Using this metal mixed powder, the metal mixed powder is put into a plasma jet (argon, argon-hydrogen, argon-helium), and the surface of the material to be sprayed is roughened in advance by grit blasting pretreatment. Laminate coating. A method of manufacturing an electrode material for a vacuum circuit breaker, wherein the metal mixed powder particles are uniformly mixed and dispersed.

The metal-sprayed composite alloy obtained in the present invention has a strong bonding force between individual particles and a strong bonding force at the interface with the material to be sprayed. Sufficient effects such as the cutoff characteristics can be obtained. In consideration of productivity and economy, the particle size of the refractory metal is preferably 53 μm or less. The content is 20 to 60% by weight of the refractory metal and 1 to 10% by weight with respect to the highly conductive metal.
% By weight and 0.1 to 1% by weight of the welding resistant metal.

According to the present invention, there is provided an electrode member for a vacuum circuit breaker, wherein the metal mixed powder is produced by a plasma spraying method to produce a metal composite alloy having a strong bonding force between individual particles and having no defect.

In the present invention, the metal-sprayed composite member is free of chromium particles and does not float and melt into copper (electrode supporting portion), or has no phenomenon such as wall thinning due to erosion at the interface. It is possible to provide a sound electrode member for a vacuum circuit breaker in which fine refractory metals are uniformly dispersed in a conductive metal.

[0037]

(Example 1) Electrolytic copper powder having a particle diameter of 150 μm or less and a purity of 99.99%, and a particle diameter of 100 μm
Hereinafter, a chromium powder having a purity of 99.99% 20.0 to 80.0%
% Of niobium powder having a particle size of 75 to 45 μm and a purity of 99.9% was mixed with a V mixer at 150 rpm.
The powder mixed for 1 hour was sprayed onto a substrate made of oxygen-free copper by a plasma spraying method. Thermal spraying conditions are plasma gas A
r + H ₂ , plasma current 600A, plasma voltage 60
V, powder supply amount: 36 g / min, spraying distance: 100 mm, film thickness: 2 mm. (Example 2) Electrolytic copper powder having a particle size of 150 μm or less and a purity of 99.99%, and an electrolytic copper powder having a particle size of 100 μm or less and a purity of 99.99%
Chromium powder 20.0-80.0% by weight, particle size 75-45
Niobium powder having a purity of 99.9% and 1.0 wt% of niobium powder were mixed by a V mixer at 150 rpm for 1 hour, and the resulting powder was sprayed onto a substrate made of oxygen-free copper by a plasma spraying method. The spraying conditions were as follows: plasma gas Ar + H ₂ , plasma current 600 A, plasma voltage 60 V, powder supply amount 36 g /
min, spraying distance 100 mm, coating thickness 2 mm. After thermal spraying, the material to be sprayed is treated at a processing temperature of 800 in a vacuum of 10 ^-5 Torr.
Heat treatment was performed at ~ 1000 ° C for 1 hour.

Example 3 Particle size: 150 μm or less, purity: 9
9.99% electrolytic copper powder, particle size 100 μm or less, purity 9
9.9% chromium powder 20.0-80.0% by weight, particle size 75-45 μm, purity 99.9% niobium powder 1.0% by weight were mixed for 1 hour at 150 rpm using a V mixer. The powder thus obtained was sprayed onto a substrate made of oxygen-free copper by a high-speed flame spraying method. The spraying conditions were as follows: spray gas C ₃ H ₆ + O ₂ + air, powder supply amount 35 g / min, spray distance 200 mm, coating thickness 2 mm.

Example 4 Particle size: 150 μm or less, purity: 9
9.99% electrolytic copper powder, particle size 100 μm or less, purity 9
9.9% chromium powder 20.0-80.0% by weight, particle size 75-45 μm, purity 99.9% niobium powder 1.0% by weight were mixed for 1 hour at 150 rpm using a V mixer. The powder thus obtained was sprayed onto a substrate made of oxygen-free copper by a high-speed flame spraying method. The spraying conditions were as follows: spray gas C ₃ H ₆ + O ₂ + air, powder supply amount 35 g / min, spray distance 200 mm, coating thickness 2 mm. After thermal spraying, the material to be sprayed was heat-treated at a processing temperature of 800 to 1000 ° C. for 1 hour in a vacuum of 10 ⁻⁵ Torr.

FIG. 1 is a cross-sectional view of a metal spray composite alloy after thermal spraying. The arc electrode 1, the arc electrode support 2, the outer conductor connection 3, and the back conductor 4 after thermal spraying are shown. 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 (magnification: 50 times) was found to be in a matrix of flat copper particles. The fine chromium particles were flat and uniformly distributed, and had a smooth interface state although the interface had irregularities of about 40 μm. The structure (magnification: 50 times) of the member formed by the conventional powder metallurgy method had an interface configuration in which large chromium particles were distributed and the unevenness of the interface was large at about 400 μm.

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. Between the arc electrode 1 and the arc electrode support 2, there is provided a back conductor 4 having a smaller diameter and a smaller diameter. Further, the interface between the arc electrode material and the arc electrode supporting member is completely and continuously integrated in a metallographic manner, and it can be seen that joining by brazing or the like is unnecessary.

As shown in FIG. 1, in the electrode obtained by cutting, the interface between the arc electrode 1 and the arc electrode support 2 forms an alloy. It is strong against arcs and can contribute to improvement of current interrupting capacity.

[0043]

[Table 1]

Table 1 shows the thickness reduction of the arc electrode 1 after plasma spraying. There is no thickness reduction of the member of the present invention. The conventional member is greatly reduced in thickness to 3.0 mm. From this, the member of the present invention is a good member.

(Embodiment 5) FIG. 2 shows Embodiments 1 to 4 described above.
FIG. 2 is a cross-sectional view of a vacuum valve using an arc electrode according to FIG. The vacuum vessel is placed on an insulating cylinder 28 made of insulating material.
A ceiling 27 is provided in the lower opening to form a vacuum chamber by forming an upper and lower sealing 27, and a fixed conductor 22 forming a part of the fixed electrode 21 is vertically provided in the middle of the ceiling. In the middle of the ceiling located immediately below the fixed electrode 21, a current-carrying portion formed of a movable conductor forming a part of the movable electrode 23 is housed. The movable conductor 21 is joined to a vacuum vessel via a metal bellows 26, and opens and closes the electrodes in an airtight manner. The shield member 25 protects the insulating cylinder 28 from an arc generated between the fixed electrode 21 and the movable electrode 23 at the time of interruption, fixes the scattered molten metal, and cools the arc. Further, the configuration is such that the function of controlling ionization is not impaired.

[0046]

[Table 2]

Samples A to K shown in Table 2 are examples and samples L to
O is a comparative example.

In the cutoff test, a pair of test electrodes are incorporated in the cutoff test section, and baking is performed at 300 ° C. for 2 hours while evacuating the cutoff 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 arc discharge is performed 10 times at 100 V AC and 300 A, and then the minimum discharge voltage at the electrode gap of 2.5 mm is measured. This withstand operation was repeated 10 times and the withstand voltage measurement was 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 from the relation of circuit constants, and the test voltages 1 to 5 were set so that the cutoff current increased in 500 to 1000 A steps. 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 after cleaning the electrode surface, the interruption current is increased. And In the impulse withstand voltage measurement after interrupting the large current, the electrode gap is 2.5m after the test.
The minimum impulse withstand voltage at m was measured, and the withstand voltage characteristics after interruption of a 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.

[0049]

[Table 3]

Table 3 shows the results of the breaking 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 6) FIG. 3 is a plan view of a spiral type electrode in this embodiment, and FIG. 4 is a sectional view of the electrode member of FIG. 1 formed by the plasma spraying shown in the above-mentioned Embodiment 5. . As shown in these figures, the electrodes are further cut by arc processing surfaces 5B and 5B on the outside so as to serve as contact surfaces with a perfect circular recess 5A at the center of the electrode.
C, 5D are provided integrally, and each arc running surface 5B, 5C, 5
D, three slit grooves 13A to 13C extending from the concave portion 5A to a position just before the outer end 5E of the arc running surfaces 5B, 5C, 5D.
Is spirally cut into an arc electrode 1 and an arc electrode support. The spiral structure has three grooves, but may have four or five grooves, and may have a curved line 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 arc running surface 5B, which is a concave portion, to the electrode side surface from the outer peripheral end portion 13E of the slit groove. A plurality of arc running surfaces 5B to 5D are formed between the slit grooves. The connecting portion 14 straddles the slit grooves 13A to 13C between the outer peripheral end portion 13E and the arc running surface 5B 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 5B to 5D.

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. Since the surfaces of the connecting portion 14 and the two arc running surfaces 5B to 5D can be made equal in height, not only can the axial direction be reduced as compared with the conventional valve, but also the electric field can be reduced without electric field concentration. In addition, the breaking current capacity can be further improved.

(Embodiment 7)

[0055]

[Table 4]

Table 4 shows the specifications of the vacuum valve at various ratings using the vacuum valve formed by spraying the above-mentioned arc electrode. FIG. 5 is a cross-sectional view of the No. 1 vacuum valve shown in Table 4, and FIG. 6 is a cross-sectional view of the No. 4 vacuum valve.

The upper and lower openings of the insulating cylinder 35 made of an insulating material are vertically integrated with seal rings 38a and 38b.
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, which forms 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.
So that the arc electrode 31b of the movable electrode 30b is brought into contact with and separated from the arc electrode 33b of the movable electrode 30b, and the metal bellows 37 is expanded and contracted inside the seal ring 38a located around the movable electrode rod 34. Further, a cylindrical metal plate sealing member 36 around both of the arc electrodes is provided by a vacuum vessel of an insulating cylinder 35, and the sealing member 36 is provided on the insulating cylinder 35. The structure is such that the insulation of the vacuum vessel is not impaired.

Further, the arc electrodes 31a and 31b are connected to the arc electrode supporting portions 3 obtained by the above-described plasma spraying.
2a, 32b are integrally fixed to the external conductor connection portions 33a, 3
3b and the back conductors 39a and 39b. Glass and ceramics sintered bodies are used for the insulating cylinder 35 to the vacuum container. From the insulating cylinder 35, the vacuum vessel is made of glass such as copearl or the like on the seal rings 38a and 38b.
It is brazed through an alloy plate having a coefficient of thermal expansion close to that of ceramics, and is kept at a 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. 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 figure, 43 is the outer diameter of the insulating cylinder, 44 is its length, 41 is the diameter of the conductor behind the electrode, and 40 is the diameter of the electrode. 46 is a guide, and 47 is a button. Button 47
Is a recess formed of a perfect circle having a desired depth, which is the same as the recess 5A shown in FIG. As shown in Table 3, in the vacuum valve according to the present invention, the number of spiral grooves and the number of spirals are different depending on the difference in rated breaking capacity.

FIG. 7 is a block diagram of a vacuum circuit breaker showing the vacuum valve 59 and its operating device according to the present invention.

This is a small and lightweight structure in which the operating mechanism section 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 an electromagnetically operated mechanical free-drawing machine with a simple structure, small size and light weight. Shock is small because the opening and closing stroke is small and the mass of the movable part is small. On the front of the main unit, in addition to the manually connected secondary terminal,
An open / close indicator, an operation counter, a manual pull-out button, a manual input device, a pull-out device, an interlock lever, and the like are arranged.

(A) Closed state The closed state of the circuit breaker is shown, 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 contact force between the main electrodes, the force of the quick-release spring, and the electromagnetic force due to the short-circuit current are applied to the support lever 66 and the block 67.
Is held in. 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 is held by the support lever 66.

(B) Free-drawing state The movable main electrode is moved downward by the separating operation, and an arc is generated from the separation of the fixed and movable main electrodes. The arc is extinguished in a short time due to the high dielectric strength in the vacuum and the vigorous diffusion action.

When the extraction coil 72 is excited, the extraction lever 73 disengages the block 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 free-drawing method 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 returned by the reset spring 74 and the block 67 is simultaneously 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 action 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 cutting 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 3kV, 6
When directly opening and closing a kV rotating machine with a vacuum circuit breaker, suppress the surge voltage by contacting the surge absorber with the circuit.
Equipment needs to be protected. 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-described embodiment, 7.2 kV and 31.45 kA can be cut off at a pressure of 150 kg and a cutoff speed of 0.93 m / sec.

FIG. 8 shows the internal structure of the vacuum switchgear two-stage switchgear of this embodiment. 91 is an upper circuit breaker compartment, 92 is a metal clad frame compartment, 93 is a lower circuit breaker compartment, 9
Reference numeral 4 denotes a bus compartment, 95 denotes a current transformer, 96 denotes a connection conductor, 97 denotes a cable compartment, 98 denotes a control lead-in cable portion, and 99 denotes 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.

[0073]

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 supporting member for supporting the arc electrode, and a coil electrode connected to the supporting member, a fine metal By forming a metal composite alloy by spraying the mixed powder, the crystal grains of all highly conductive metals, refractory metals, voltage-resistant metals and welding-resistant metals become fine, and high-performance electrode members with good initial performance can be obtained. The arc electrode and the arc electrode supporting member, the coil electrode material, and preferably the conductive rod are obtained by a non-joining sintering or frictional pressure bonding process, and have a monolithically integrated structure.
Since the brazing of the support member and the coil electrode is not required, a welding failure due to electrode deformation can be prevented by improving the strength of the arc electrode support member and the coil electrode material, so that a more reliable and safe vacuum circuit breaker can be obtained. Can be

According to the present invention, in a vacuum valve having a fixed-side electrode and a movable-side electrode having an arc electrode and a support member supporting the arc electrode and thereafter, the height of the arc electrode and the arc electrode support member and thereafter is increased. The conductive metal has an integral structure by thermal spraying. Preferably, the support member and the subsequent members are integrated by diffusion heat treatment after thermal spraying, wherein 0.01 to 0.5% by weight of Cr, Ag, V, N
It is preferably composed of a Cu alloy containing b, Zr, Si, W, Be, etc., which reduces the machining process and assembly process of each member involved in brazing, and the destruction of the electrode material due to poor brazing. It also helps to prevent falling off and to improve the strength, and prevents welding failure due to electrode deformation. Furthermore,
Since a large amount of low melting point metal such as Pb is contained in the arc electrode and welding can be prevented, a more compact, 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 cross-sectional view of an electrode formed by metal spraying of the present invention.

FIG. 2 is a sectional view of a vacuum valve.

FIG. 3 is a plan view of an electrode having a spiral groove according to the present invention.

FIG. 4 is a sectional view of an electrode having a spiral groove of the present invention.

FIG. 5 is a sectional view of a vacuum valve.

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

FIG. 7 is an overall configuration diagram of a vacuum circuit breaker.

FIG. 8 is a configuration diagram of a vacuum circuit breaker two-stage switchgear.

[Explanation of symbols]

1, 31a, 31b: arc electrode, 2: arc electrode support, 3, 33a, 33b: external conductor connection, 4, 39a,
39b: back conductor, 5A: recess, 5B, 5C, 5D: arc running surface, 5E: electrode outer peripheral end, 13, 13A, 13B,
13C: slit groove, 14: connecting part, L: width, 30a:
Fixed electrode, 30b movable electrode, 34 electrode rod, 35 insulating cylinder, 36 sealing member, 37 bellows, 38a,
38b: seal ring, 60: epoxy resin cylinder, 61
... Insulated operating rod, 62 ... Top terminal, 63 ... Current collector, 6
4 lower terminal, 65 contact spring, 66 support lever, 6
8: Plunger, 71: Main lever, 72: Extraction coil, 75: Input coil, 76: Exhaust cylinder.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masao Shimizu 7-1-1, Omikacho, Hitachi City, Ibaraki Prefecture Inside the Hitachi Research Laboratory, Hitachi, Ltd. (72) Katsuhiro Komuro 7-1, Omikamachi, Hitachi City, Ibaraki Prefecture No. 1 Hitachi, Ltd. Hitachi Research Laboratory (72) Inventor Akira Mehata 7-1-1, Omika-cho, Hitachi City, Ibaraki Prefecture Inside Hitachi Research Laboratory Hitachi Research Laboratory, Ltd. (72) Inventor Tohru Tanizu Hitachi, Ibaraki Prefecture 1-1-1, Kokubucho, Kokubu Factory, Hitachi, Ltd. (72) Inventor Yoshimi Hakamada 1-1-1, Kokubuncho, Hitachi, Hitachi, Ibaraki Prefecture F-term, Hitachi Kokubu Factory 5G026 BA02 BB02 BB03 BB04 BB08 BB10 BB12 BB14 BB15 BB16 BB17 BB18 BB22 BB24 BB25 BB27 BB30 BC04 BC08 DA01

Claims (9)

[Claims] A vacuum valve having a fixed side electrode and a movable side electrode in a vacuum vessel; and an opening / closing means for driving the movable side electrode, wherein the fixed side electrode and the movable side electrode are an arc electrode member. A vacuum circuit breaker provided with an arc electrode support member for supporting the arc electrode member, wherein the arc electrode member has a highly conductive metal and a refractory metal having a higher melting point than the highly conductive metal; A vacuum circuit breaker, wherein the conductive metal and the refractory metal have a flat particle shape. 2. A vacuum valve having a fixed side electrode and a movable side electrode in a vacuum vessel, and opening / closing means for driving the movable side electrode, wherein the fixed side electrode and the movable side electrode are an arc electrode member. A vacuum circuit breaker comprising an arc electrode support member for supporting the arc electrode member, wherein the arc electrode member has a highly conductive metal and a refractory metal having a higher melting point than the highly conductive metal, A vacuum circuit breaker, wherein irregularities at an interface between an arc electrode member and an arc electrode support member are 100 μm or less. 3. A vacuum valve having a fixed electrode and a movable electrode in a vacuum vessel, and the arc electrode member has a highly conductive metal and a refractory metal having a higher melting point than the highly conductive metal. ,
A vacuum circuit breaker characterized by being formed by thermal spraying. 4. A vacuum valve having a fixed side electrode and a movable side electrode in a vacuum vessel, wherein both electrodes support an arc electrode member having a refractory metal and a highly conductive metal, and support the arc electrode member. An arc electrode support member or a current-carrying electrode rod made of a highly conductive metal, wherein the arc electrode member has a highly conductive metal and a refractory metal having a higher melting point than the highly conductive metal. A vacuum valve, wherein the conductive metal and the refractory metal have a flat particle shape. 5. A vacuum valve having a fixed side electrode and a movable side electrode in a vacuum vessel, wherein both electrodes support an arc electrode member having a refractory metal and a highly conductive metal, and support the arc electrode member. An arc electrode support member or a current-carrying electrode rod made of a highly conductive metal, the arc electrode member comprising a highly conductive metal and a refractory metal having a higher melting point than the highly conductive metal, A vacuum valve wherein irregularities at an interface between an electrode member and an arc electrode support member are 100 μm or less. 6. A vacuum valve having a fixed side electrode and a movable side electrode in a vacuum vessel, wherein the two electrodes support an arc electrode member having a refractory metal and a highly conductive metal, and support the arc electrode member. An arc electrode support member or a conductive electrode rod made of a highly conductive metal, the arc electrode member having a highly conductive metal and a refractory metal having a higher melting point than the highly conductive metal, and A vacuum valve characterized by being formed. 7. The fixed electrode and the movable electrode according to claim 1, wherein the fixed electrode and the movable electrode are connected to the arc electrode support, and the back conductor has a diameter smaller than the support and a diameter larger than the back conductor. A vacuum circuit breaker having an external conductor connection portion. 8. The fixed electrode and the movable electrode according to claim 4, wherein the fixed electrode and the movable electrode are connected to the arc electrode support, and the back conductor has a diameter smaller than the support and a diameter larger than the back conductor. A vacuum valve having an external conductor connection portion as described above. 9. An arc electrode comprising: an arc electrode member having a refractory metal and a highly conductive metal; and an arc electrode support member or a current-carrying electrode rod made of a highly conductive metal for supporting the arc electrode member. An electrical contact, wherein the member is integrally formed by metal spraying.