JP5159947B2 - Electrical contact for vacuum valve and vacuum circuit breaker using the same - Google Patents

Description

  The present invention relates to a novel electrical contact for a vacuum valve used for a vacuum circuit breaker, a vacuum switch and the like.

  Power receiving and distribution equipment such as a vacuum circuit breaker is required to be small and inexpensive. For this purpose, it is necessary to reduce the strength of the electrical contacts in the vacuum valve and to reduce the pulling force when the electrical contacts are welded together by Joule heat, thereby reducing the size of the operating mechanism that performs the opening and closing operation of the electrical contacts. is there. Most of the electrical contacts are made of a Cr—Cu based sintered alloy in which Cr is dispersed in a Cu matrix. As a means for reducing the strength, a low melting point metal such as Te is used as shown in Patent Documents 1 to 3. The method of adding is used.

JP 2005-135778 A JP 2006-140073 A Japanese Patent Laid-Open No. 2003-223834

  In conventional Cr-Cu-based electrical contacts, several parts by weight of low melting point metals such as Te are added as an anti-welding component that facilitates the separation of contacts when welding occurs, or as a component that suppresses contact surface roughness after current interruption. It had been. When this amount of low melting point metal is added, defects may be generated in the Cu matrix that is a current-carrying component or sintering may be insufficient, and good current-carrying performance and interruption performance may not be obtained. Also, when the vacuum valve is manufactured by vacuum sealing brazing, the low melting point metal is volatilized from the electrical contacts, which impairs the soundness of the brazed part and may cause a decrease in the degree of vacuum in the vacuum valve. On the other hand, when the amount of the low melting point metal added is less than the appropriate amount, the strength of the electrical contact is not sufficiently reduced, and the effect of reducing the separating force may be insufficient.

  The object of the present invention is to solve the problems of the prior art, fully exhibit the effect of reducing the welding pull-off force, have excellent breaking performance and energization performance, and enable significant downsizing of vacuum circuit breakers and the like It is to provide an electrical contact and a vacuum circuit breaker using the same.

  The electrical contact of the present invention is characterized in that it has Cr powder dispersed in a Cu matrix, and a coating layer made of a non-reactive / non-solid component with respect to Cu is provided on the Cr powder surface.

  Further, the coating layer comprising the non-reacting / non-solid solution component is characterized by comprising any one of C, Mo, and W.

  Further, the thickness of the coating layer made of non-reactive and non-solid components on the surface of the Cr powder is 0.01 μm or more.

  Further, 75% or more of the surface of the Cr powder is covered with a coating layer made of the non-reactive / non-solid solution component.

  The interface between the coating layer of Cr powder and the Cu matrix is characterized in that voids are present in 70% to 90% thereof.

  Further, the content of the Cr powder is 15 to 40% by weight, and the electric contact breaking performance is guaranteed.

  Furthermore, in the electrical contact manufacturing method, a mixed powder obtained by mixing Cu powder and Cr powder coated with a non-reactive / non-soluble component with respect to Cu is pressed and heated at a temperature not higher than the melting point of Cu. It is characterized by sintering.

  Further, the Cr powder has a particle size of 104 μm or less, the Cu powder has a particle size of 61 μm or less, ensures dispersibility of the Cr powder in the Cu matrix, and ensures the sinterability of the Cu powder. And

  A disk-shaped central hole formed at the center of the disk-shaped circle, and a plurality of through slit grooves formed from the center of the circle toward the outer periphery without contact with the center hole; And the disk-shaped member is an electrode having an electrode bar integrally formed on the surface opposite to the arc generating surface of the disk-shaped member.

  Further, in the vacuum valve provided with a pair of fixed side electrode and movable side electrode in the vacuum vessel, at least one of the fixed side electrode and the movable side electrode has the above-described electrical contact.

  A vacuum valve having a pair of fixed and movable electrodes in a vacuum vessel; and a conductor terminal connected to the fixed and movable electrodes inside the vacuum valve outside the vacuum valve; In a vacuum circuit breaker provided with opening / closing means for driving the movable side electrode, the vacuum valve is composed of the above-described vacuum valve.

  The electrical contact of the present invention has Cr and Cu, and Cu and non-reactive / non-solid components, Cr powder is dispersed in the Cu matrix, and Cu and non-reactive / non-solid components are present on the surface of the Cr powder. The coating layer is made of, and in the sintering process, voids are formed between Cr and Cu, and the solid bonding of Cr and Cu prevents solid bonding between the two, reducing the interfacial strength between Cr and Cu, and welding Thus, the force for separating the electrical contacts can be reduced.

The schematic diagram which shows the principle of this invention. The horizontal sectional view which shows the structure of the electrode which concerns on Example 1 of this invention. II-II sectional view taken on the line in FIG. The schematic diagram of the vacuum valve which concerns on Example 2 of this invention. The schematic diagram of the vacuum circuit breaker which concerns on Example 3 of this invention. The schematic diagram of the load switch for roadside installation transformers which concerns on Example 4 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Electrical contact, 1a ... Fixed side electrical contact, 1b ... Movable side electrical contact, 2 ... Slit groove 4, 4a, 4b ... Electrode rod, 6a ... Fixed side electrode, 6b ... Movable side electrode, 14 ... Vacuum valve, 17 ... upper terminal, 18 ... current collector, G ... gap, A ... coating layer

  The present inventors have found that the cause of the strength reduction in the Cr—Cu sintered electrical contact to which the low melting point metal is added is due to a physical separation between the Cr powder and the Cu matrix. That is, in the conventional sintering process, the low melting point metal is preferentially melted and moved to form voids at the interface between Cr and Cu, resulting in a decrease in interface strength and a decrease in strength as a contact material. From this, if the Cr powder surface is coated with a non-reactive / non-solid component of Cu, Cr and Cu are more physically physically separated along with the sintering shrinkage of the Cu matrix during the sintering process. Obtained knowledge.

  FIG. 1 is a schematic diagram illustrating the principle of the present invention. (A) shows the Cr particle interface in the Cu matrix. In the case of the Cr—Cu system, some Cr diffuses in the Cr matrix to form the solid solution layer S and generate a strong fixing force, so that the welding resistance is poor. (B) shows an example in which Te is added to improve the welding resistance. As the sintering process proceeds, Te melts and moves to form a gap G between Cr and Cu (according to the shrinkage of the Cu matrix), so that the welding resistance is improved. (C) shows the configuration of the present invention. By providing the coating layer A of a substance that is a non-reactive / non-solid component with Cr on the Cr surface, voids G are formed between Cr and Cu during the sintering process, and the welding resistance is improved.

  As a component of the coating layer A that is non-reactive / non-solid solution with Cu, any one of C, Mo, and W is desirable. By coating these components with Cr powder, it is possible to prevent Cr from dissolving in Cu and strengthening the bond between them. Further, by using only one of C, Mo, and W, it is possible to prevent embrittlement destruction of the coating layer due to the compound generation due to the reaction between the non-reacting / non-solid solution components.

  The coating thickness of the coating layer A of the non-reactive / non-solid component on the Cr powder surface is set to 0.01 μm or more, and the coating area having this coating thickness is set to 75% or more of the Cr powder surface. The effect of reducing the interfacial strength between Cr and Cu is obtained. If the thickness and area are smaller than these values, the effect of preventing Cr from dissolving in Cu is not sufficient, and the effect of reducing the welding separation force cannot be obtained.

  Due to the coating layer A of the non-reactive / non-solid component on the surface of the Cr powder, a gap G is generated at the interface between the sintered coating layer A and the Cu matrix. This is because chemical bonding does not occur at the interface between the coating layer A and the Cu matrix, and physically separates at the interface with Cu sintering shrinkage. This gap G is desirably present in 70% to 90% of the interface. If it is smaller than this value, the effect of reducing the interface strength becomes insufficient. It is better that the gap G is 90% or more of the interface, but since there is a portion that physically contacts due to the influence of the interface shape or the like, a void ratio exceeding 90% hardly occurs.

  In order to obtain the effect of reducing the welding separation force by the coating layer A of the non-reactive / non-solid component on the Cr powder surface as described above, the reaction between the Cr powder and the non-reactive / non-solid component It is desirable not to form a product (compound). This is because, when a compound is formed around Cr powder, when the compound layer is decomposed, the contained Cr may be dissolved in the Cu matrix, and the bonding at the interface between Cr and Cu may be promoted and the interface strength may not be lowered. Because there is. Further, when the compound is produced, the Cr powder may be refined with the reaction and the withstand voltage performance may be improved. On the other hand, there is a risk that the interruption performance unique to Cr may be impaired. Therefore, the surface of the Cr powder is preferably coated with a single layer of Cu and non-reacting / non-solid component of any one of C, Mo and W in order to solve the object of the present invention.

  The Cr content in the electrical contact of the present invention is desirably in the range of 15 to 40% by weight. If the Cr content is less than this, the withstand voltage performance will be reduced, and if it is more than this, the current-carrying performance will be reduced and the sinterability will be reduced, making it difficult to produce dense electrical contacts, and sufficient breaking performance will not be obtained. .

  The method for producing an electrical contact of the present invention comprises mixing Cu powder and Cr powder coated with Cu and a non-reactive / non-soluble component, press-molding this mixed powder, and then having a melting point of Cu or lower. Since it is heated and sintered at a temperature, it can be manufactured relatively easily at low cost. Coating of Cr powder with non-reactive and non-solid components is possible by applying physical vapor deposition methods such as vapor deposition and other surface treatment technologies, and applying mechanical composite technology such as mechano-fusion methods. You can also The pressure forming of the mixed powder can be performed by using a final-shaped mold, whereby an electrical contact having a final shape can be manufactured without using machining after heat sintering. This heat sintering is performed in a vacuum or in an inert or reducing atmosphere, so that oxidation during heating can be prevented and the vacuum valve can be kept at a high vacuum. The particle size of the raw material powder used is desirably 104 μm or less for Cr powder and 61 μm or less for Cu powder. If each particle size is larger than this value, the uniformity of the structure after sintering is reduced, Cu is eluted at the contact surface at the time of current interruption, and welding tends to occur.

  The electrode using the electrical contact of the present invention has a disk shape, and a center hole formed at the center of the disk-shaped circle, and is formed from the center of the circle toward the outer periphery without contacting the center hole. A plurality of slit grooves penetrating through and an electrode rod integrally joined to the surface opposite to the arc generating surface of the disk-shaped member, the disk-shaped member comprising the electrical contact of the present invention. Thus, an electrode having a desired performance which is excellent in blocking performance and has a small welding separation force can be obtained.

  The vacuum valve according to the present invention includes a pair of fixed and movable electrodes in a vacuum vessel, at least one of which is an electrode using the electrical contact according to the present invention. Further, the vacuum circuit breaker according to the present invention includes a vacuum valve provided with at least one of a fixed side electrode and a movable side electrode using the electric contact of the present invention in a vacuum vessel, and the fixed side electrode and the movable side electrode in the vacuum valve. Each of the side electrodes is provided with a conductor terminal connected to the outside of the vacuum valve and an opening / closing means for driving the movable side electrode. As a result, it has excellent breaking performance and energization performance, has a small pulling force when the electrical contacts are welded to each other, can reduce the size of the operation mechanism, and is a small and low-priced vacuum circuit breaker. Various vacuum switchgears are obtained.

  Hereinafter, the best mode for carrying out the invention will be described in detail by way of examples, but the present invention is not limited to these examples.

  An electrical contact having the composition shown in Table 1 was produced, and an electrode was produced using the electrical contact.

図２は作製した電極の構造を示す水平断面図、図３は図２のＩＩ-ＩＩ線断面図である。図２、図３において、１は電気接点、２はアークに駆動力を与えるためのスリット溝、３はステンレス製の補強板、４は電極棒、５はろう材、４４は電気接点１の中央にアークが発生して停滞するのを防ぐための中央孔である。

FIG. 2 is a horizontal sectional view showing the structure of the fabricated electrode, and FIG. 3 is a sectional view taken along the line II-II in FIG. 2 and 3, 1 is an electrical contact, 2 is a slit groove for applying a driving force to the arc, 3 is a stainless steel reinforcing plate, 4 is an electrode rod, 5 is a brazing material, and 44 is the center of the electrical contact 1. This is a central hole for preventing an arc from occurring and stagnating.

  The manufacturing method of the electrical contact 1 is as follows. First, Mo, which is a non-reactive / non-solid component with Cu, was coated on a Cr powder. In this example, Cr coating (particle size of 88 μm or less) and Mo powder (particle size: 0.7 μm) were subjected to heavy load mixing with a dancing mixer to provide Mo coating. The thickness of the Mo coating layer and the coating area ratio with respect to the Cr powder surface were adjusted by the mixing amount and mixing time of the Mo powder.

  Next, this Mo-coated Cr powder and Cu powder having a particle size of 60 μm or less were mixed by a V-type mixer at a blending ratio such that the Cr content in Table 1 was obtained. Subsequently, the mixed powder was filled in a disk-shaped mold and pressure-molded with a hydraulic press at a pressure of 400 MPa. The density of the molded body was approximately 73%. This was heated and sintered at 1060 ° C. for 2 hours in a hydrogen atmosphere at a pressure of 40 Pa to produce a sintered body as a material for the electrical contact 1. The relative density of the obtained sintered body was approximately 96%.

  The obtained sintered body was machined to produce an electrical contact 1 having the shape shown in FIG. The electrical contact 1 can also be obtained by a method in which a mixed powder is filled in a mold that can form a final shape having the slit groove 2 and the central hole 44 and sintered, and in this method, after machining, etc. Since processing is not required, it can be easily manufactured.

  As a comparative example of Example 1, an electrical contact (No. 10 in Table 1) in which Ni that was dissolved in Cu was coated with Cr powder was prepared. Ni coating on the Cr powder is performed by a plating method, and the subsequent steps are the same as described above.

  As another comparative example, an electrical contact (No. 11 in Table 1) to which Te which is one of conventional materials was added was produced. This was prepared by mixing Te powder (particle size of 45 μm or less) together with the Cr powder and Cu powder with a V-type mixer, followed by molding and sintering. The pressure molding conditions and sintering conditions are the same as above.

  As another comparative example, an electrical contact (No. 12 in Table 1) using Cu as a refractory metal other than Cr and Mo which is a non-reactive / non-solid component was prepared. This was prepared by mixing Mo powder (particle size of 63 μm or less) together with the above Cu powder with a V-type mixer, followed by molding and sintering. The pressure molding conditions and sintering conditions are the same as above.

The method for producing the electrode is as follows. The electrode bar 4 is made of oxygen-free copper, and the reinforcing plate 3 is made by machining in advance with SUS304. The brazing material 5 was placed between them, and this was heated in a vacuum of 8.2 × 10 ⁻⁴ Pa or less at 970 ° C. × 10 minutes to produce the electrode shown in FIG. This electrode is used for a vacuum valve for a rated voltage of 7.2 kV, a rated current of 600 A, and a rated breaking current of 20 kA. If the strength of the electrical contact 1 is sufficient, the reinforcing plate 3 may be omitted.

  A vacuum valve was produced using the electrode produced in Example 1. The specifications of the vacuum valve are a rated voltage of 7.2 kV, a rated current of 600 A, and a rated breaking current of 20 kA.

  FIG. 4 is a schematic diagram showing the structure of the vacuum valve 14 according to the present embodiment. In FIG. 4, 1a is a fixed-side electrical contact, 1b is a movable-side electrical contact, 3a and 3b are reinforcing plates, 4a is a fixed-side electrode rod, and 4b is a movable-side electrode rod. 6b is configured. In the second embodiment, the slit grooves 2 of the electric contacts on the fixed side and the movable side are installed so as to coincide with each other on the contact surface.

  The movable side electrode 6b is brazed and joined to the movable side holder 12 via a movable side shield 8 that prevents scattering of metal vapor or the like at the time of interruption. These are brazed and sealed to a high vacuum by the fixed side end plate 9a, the movable side end plate 9b, and the insulating cylinder 13, and are connected to the external conductor through the screw portions of the fixed side electrode 6a and the movable side holder 12. A shield 7 is provided on the inner surface of the insulating cylinder 13 to prevent scattering of metal vapor or the like at the time of interruption, and a guide 11 for supporting a sliding portion is provided between the movable side end plate 9b and the movable side holder 12. Provided. A bellows 10 is provided between the movable side shield 8 and the movable side end plate 9b, and the fixed side electrode 6a and the movable side electrode are moved up and down by moving the movable side holder 12 while keeping the vacuum valve 14 in a vacuum. 6b can be opened and closed.

  Next, a vacuum circuit breaker equipped with the vacuum valve produced in Example 2 was produced. FIG. 5 is a schematic diagram showing a vacuum circuit breaker showing the vacuum valve 14 and its operation mechanism according to the present invention.

  The vacuum circuit breaker has a structure in which three sets of three-phase epoxy cylinders 15 that support the vacuum valve 14 are disposed on the back surface with the operation mechanism portion disposed on the front surface. The vacuum valve 14 is opened and closed by the operation mechanism unit via the insulating operation rod 16.

  When the vacuum circuit breaker is closed, current flows through the upper terminal 17, the electrical contacts 1 a and 1 b, the current collector 18, and the lower terminal 19. The contact force between the electrodes is maintained by a contact spring 20 attached to the insulating operation rod 16. The contact force between the electrodes and the electromagnetic force due to the short-circuit current are held by the support lever 21 and the prop 22. When the closing coil 30 is excited, the plunger 23 pushes up the roller 25 through the knocking rod 24 from the open circuit state, rotates the main lever 26 to close the space between the electrodes, and then holds it with the support lever 21.

  When opening the vacuum circuit breaker, when the tripping coil 27 is excited, the tripping lever 28 disengages the prop 22 and the main lever 26 rotates to open the electrodes. In the open circuit state of the vacuum circuit breaker, after the electrodes are opened, the link is restored by the reset spring 29 and the prop 22 is engaged at the same time. When the closing coil 30 is excited in this state, a closed state is obtained. In addition, 31 is an exhaust pipe.

  The electrical contact produced in Example 1 is used for the vacuum valve with the rated voltage of 7.2 kV, the rated current of 600 A, and the rated breaking current of 20 kA shown in Example 2, and is mounted on the vacuum circuit breaker shown in Example 3 for performance test. Went.

  Table 1 is a table showing the electrical contact composition and performance test results. 1-No. No. 5 is an example of the present invention, No. 6-No. 12 shows a comparative example. Each performance is No. which is a conventional contact material. The results were expressed as relative values based on 11 results.

  The coating layer thickness of the Cr powder is a value measured using an electron microscope and an X-ray analyzer after polishing the coated Cr powder and polishing the powder cross section. The area ratio of the coating layer was represented by the ratio of the coating component detection area to the powder surface area measured by measuring the coating component distribution on the powder surface with an X-ray analyzer. The porosity at the interface between the refractory metal powder or its coating layer and the Cu matrix was expressed by the ratio of the void existing length to the interface length by observing a cross section of the sintered electrical contact with an electron microscope.

  No. No. 6 does not satisfy the range of the present invention in both the thickness and area ratio of the Mo coating layer on the Cr powder surface. Compared to 11, it is inferior in separability.

  No. No. 7 has an area ratio of the coating layer that is less than the range of the present invention. Although the solid solution of Cr to Cu is suppressed to some extent and the electrical conductivity is improved, the separability is inferior. There is no advantage to replace 11.

  No. 8 and no. In No. 9, the Cr content in the electrical contact is outside the scope of the present invention. No. No. 8 is excellent in current-carrying performance and current interruption performance because it has a small amount of high-resistance Cr, and the separability is improved by the Mo coating of Cr powder. No. No. 9 has excellent withstand voltage performance due to the large amount of Cr, which is a refractory metal, and the absolute value of the Mo coating area is increased and a significant improvement in the separability can be seen, but the conductivity and current interruption performance are reduced.

  No. 10 is a coating of Ni, which is a component that dissolves in Cu, on the Cr powder. Although the Ni coating area ratio of the Cr powder is almost 100%, Ni is dissolved in the Cu matrix after sintering. There are almost no voids at the interface. Thereby, the electroconductivity of Cu matrix falls, and while electroconductivity and electric current interruption performance fall significantly, it is inferior to separability. From this, it can be said that the coating component of Cr powder needs to be non-reactive and non-solid solution with Cu.

  No. No. 12 contains Mo which is a non-reactive / non-solid component with Cu as a refractory metal instead of Cr. Mo does not dissolve in the Cu matrix, and there are sufficient gaps at the interface. Therefore, conductivity and detachability are improved and withstand voltage is high, but Mo contributes less to current interruption than Cr. For this reason, the current interruption performance is significantly reduced.

  Compared to the above comparative example, the No. 1-No. In all cases, the separability of 5 is greatly improved, and no significant deterioration is observed in other performances. In addition, since the influence of Cr content is large for the current carrying performance, the current interruption performance and the voltage resistance, No. 3 and no. These performances are reduced by the amount of Cr at 5, but both are practically acceptable.

  Thus, the electrical contact according to the present invention greatly improves the separation force between the welded contacts by reducing the interfacial strength of Cr and Cu while having excellent breaking performance, energization performance and withstand voltage performance. Thus, a vacuum valve and a vacuum circuit breaker that can be reduced and the operation mechanism portion can be reduced in size can be obtained.

  The vacuum valve produced in Example 2 was mounted on a vacuum switchgear other than the vacuum circuit breaker. FIG. 6 is a schematic diagram showing a load switch for a roadside installation transformer on which the vacuum valve 14 produced in Example 2 is mounted.

  In this load switch, a plurality of pairs of vacuum valves 14 corresponding to main circuit switching units are housed in a vacuum-sealed outer vacuum container 32. The outer vacuum container 32 includes an upper plate member 33, a lower plate member 34, and a side plate member 35, and the periphery (edge) of each plate member is joined to each other by welding and is installed together with the equipment main body.

  An upper through hole 36 is formed in the upper plate member 33, and an annular insulating upper base 37 is fixed to an edge of each upper through hole 36 so as to cover each upper through hole 36. A cylindrical movable electrode rod 4b is inserted into a circular space formed at the center of each upper base 37 so as to freely reciprocate (up and down). That is, each upper through hole 36 is closed by the upper base 37 and the movable electrode rod 4b.

  The axial end (upper side) of the movable electrode rod 4b is connected to an electromagnetic operating device installed outside the outer vacuum vessel 32. Further, on the lower side of the upper plate member 33, an outer bellows 38 is disposed so as to reciprocate in the vertical direction along the edge of each upper through hole 36. Each outer bellows 38 has an upper plate member on one end side in the axial direction. The other end side in the axial direction is fixed to the outer peripheral surface of each movable electrode rod 4b. That is, in order to make the outer vacuum container 32 have a hermetically sealed structure, outer bellows 38 are arranged at the edge of each upper through hole 36 along the axial direction of each movable electrode rod 4b. In addition, an exhaust pipe (not shown) is connected to the upper plate member 33, and the inside of the outer vacuum vessel 32 is evacuated through the exhaust pipe.

  On the other hand, a lower through hole 39 is formed in the lower plate member 34, and an insulating bushing 40 is fixed to an edge of each lower through hole 39 so as to cover each lower through hole 39. An annular insulating lower base 41 is fixed to the bottom of each insulating bushing 40. A cylindrical fixed electrode rod 4a is inserted into the circular space at the center of each lower base 41. That is, the lower through holes 39 formed in the lower plate member 34 are closed by the insulating bushing 40, the lower base 41, and the fixed electrode rod 4a, respectively. The lower side in the axial direction of the fixed electrode rod 4a is connected to a power distribution cable disposed outside the outer vacuum vessel 32.

  Inside the outer vacuum vessel 32 is housed a vacuum valve 14 corresponding to the main circuit opening / closing portion of the load switch, and each movable electrode bar 4b has a flexible flexible conductor having two curved portions. They are connected to each other via 42. The flexible conductor 42 is configured by alternately laminating a plurality of copper plates and stainless steel plates, which are conductive plate materials having two curved portions in the axial direction. A through hole 43 is formed in the flexible conductor 42, and each movable electrode rod 4 b is inserted into each through hole 43 and connected to each other.

As described above, the vacuum valve according to the present invention produced in Example 2 can be applied to a load switch for a roadside installation transformer, and also applied to various vacuum switchgears such as a vacuum insulation switchgear. it can.

Claims (5)

In an electrical contact having a Cu matrix and Cr powder dispersed in the Cu matrix, a coating layer made of a non-reactive and non-solid component with respect to Cu is provided on the surface of the Cr powder. It consists of any one of Mo and W, the thickness of the coating layer is 0.01 μm or more, and 75% or more of the surface of the Cr powder is coated with the coating layer, and the coating of the Cr powder An electrical contact characterized in that voids exist in 70% to 90% of the interface between the layer and the Cu matrix. The electrical contact according to claim 1 , wherein the content of the Cr powder is 15 to 40% by weight. It has a disk shape, and has a center hole formed at the center of the disk-shaped circle and a plurality of through slit grooves formed from the center of the circle toward the outer periphery without contacting the center hole. An electrode comprising: an electrode rod comprising the electrical contact according to claim 1 or 2 and integrally joined to a surface opposite to an arc generating surface of the disk-shaped member. A vacuum valve comprising a pair of fixed and movable electrodes in a vacuum vessel, wherein at least one of the fixed and movable electrodes comprises the electrode according to claim 3 . A vacuum valve having a pair of fixed-side electrode and movable-side electrode in a vacuum vessel; a conductor terminal connected to each of the fixed-side electrode and movable-side electrode in the vacuum valve; and the movable terminal A vacuum circuit breaker comprising an opening / closing means for driving a side electrode, wherein the vacuum valve comprises the vacuum valve according to claim 4 .

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