JP2020198246A - Vacuum valve and manufacturing method thereof - Google Patents

Abstract

To improve a joining structure of each of members that makes up a vacuum valve.SOLUTION: A vacuum valve according to an embodiment includes a plurality of members, a sintered body of metal nanoparticles, and a metal coating. The plurality of members include a first member and a second member. The sintered body connects the first member and the second member. The coating covers the outer surface of the sintered body exposed from the first member and the second member.SELECTED DRAWING: Figure 2

Description

Embodiments of the present invention relate to vacuum valves and methods of manufacturing them.

A vacuum valve including a pair of contacts that can be brought into contact with each other, a pair of electrodes to which each contact is connected, an insulating container that houses these contacts and electrodes, and a metal fitting that closes the opening of the insulating container is known. .. The members that make up the vacuum valve are joined, for example, by brazing.

Japanese Patent No. 5139161 Japanese Patent No. 4458977 Japanese Patent No. 5824201

There is room for improvement in the joining of the members that make up the vacuum valve. For example, during brazing, each member constituting the vacuum valve is heated to a temperature equal to or higher than the solidus temperature of the brazing material. During cooling, thermal stress is generated due to the difference in the coefficient of linear expansion of each member, so countermeasures are required. In addition, each member must be formed of a material that can sufficiently withstand the temperature at which the brazing material is melted, which limits the material selection of each member.

An object to be solved by the present invention is to improve the joining structure of each member constituting the vacuum valve.

The vacuum valve according to one embodiment includes a plurality of members, a sintered body of metal nanoparticles, and a metal covering body. The plurality of members include a first member and a second member. The sintered body connects the first member and the second member. The covering covers the outer surface of the sintered body exposed from the first member and the second member.

The method of matching the vacuum valve according to the embodiment is to dispose a bonding material containing metal nanoparticles between the first member and the second member, and to dispose a metal molten material around the bonding material. And, the metal nanoparticles are sintered to form a sintered body that joins the first member and the second member, and the molten material is melted and exposed from the first member and the second member. Includes forming a coating that covers the outer surface of the sintered body.

FIG. 1 is a cross-sectional view showing a schematic configuration of a vacuum valve according to the first embodiment. FIG. 2 is a cross-sectional view schematically showing a joint structure of an insulating container and a metal fitting according to the first embodiment. FIG. 3 is a flowchart illustrating a method for manufacturing a vacuum valve according to the first embodiment. FIG. 4 is a schematic perspective view showing a part of the steps of the manufacturing method shown in FIG. FIG. 5 is a schematic cross-sectional view showing another part of the process of the manufacturing method shown in FIG. FIG. 6 is a schematic cross-sectional view of the vacuum valve according to the second embodiment.

Some embodiments will be described with reference to the drawings. The vacuum valve shown in each figure is an example, and a part of the configuration disclosed in each embodiment can be applied to a vacuum valve having another structure. Further, in each figure, the relative size and position of each member constituting the vacuum valve may be schematically shown.

[First Embodiment]
FIG. 1 is a cross-sectional view showing a schematic configuration of the vacuum valve 1 according to the first embodiment. The vacuum valve 1 can be used as, for example, a vacuum circuit breaker. Further, this vacuum circuit breaker may be used for a switch gear.

In the example of FIG. 1, the vacuum valve 1 includes an insulating container 2, a first metal fitting 3A, a second metal fitting 3B, a first energizing shaft 4A, a second energizing shaft 4B, a first electrode 5A, and a second. It includes an electrode 5B, a shield 6, a bellows 7, and a cover 8.

The insulating container 2 houses the first electrode 5A, the second electrode 5B, the shield 6, the bellows 7, and the cover 8. One end of the first energizing shaft 4A and the second energizing shaft 4B is located inside the insulating container 2, and the other end is located outside the insulating container 2.

For example, the insulating container 2 has a cylindrical shape centered on the shaft AX of the vacuum valve 1, and has a first opening 21 at the upper part in the drawing, a second opening 22 at the lower part in the drawing, an outer peripheral surface 23, and an inner peripheral surface. It has 24 and. The insulating container 2 can be formed of insulating ceramics such as alumina, but is not limited to this example.

The first metal fitting 3A closes the first opening 21 of the insulating container 2. The second metal fitting 3B closes the second opening 22 of the insulating container 2. The first metal fitting 3A has, for example, a disk shape, and has a first hole 31A for passing the first energizing shaft 4A. The second metal fitting 3B has, for example, a disk shape and has a second hole 31B for passing the second energizing shaft 4B. The first metal fitting 3A and the second metal fitting 3B can be formed of a metal material containing aluminum as a main component. In the present embodiment, the expression that a specific material is the main component of a certain member means that the content of the specific material is the largest among the materials (components) contained in the member. The first metal fitting 3A and the second metal fitting 3B may be made of other materials such as stainless steel.

Both the first energizing shaft 4A and the second energizing shaft 4B extend along the shaft AX. The first energizing shaft 4A is passed through the first hole 31A of the first metal fitting 3A and is joined to the inner surface of the first hole 31A. The second energizing shaft 4B is passed through the second hole 31B of the second metal fitting 3B. A gap is provided between the second energizing shaft 4B and the inner surface of the second hole 31B. The first energizing shaft 4A and the second energizing shaft 4B can be formed of a metal material containing aluminum as a main component. The first energizing shaft 4A and the second energizing shaft 4B may be formed of other materials such as oxygen-free copper.

The first electrode 5A includes a first coil 51A supported by the first energizing shaft 4A and a first contact 52A connected to the first coil 51A. For example, the first coil 51A is joined to the end of the first energizing shaft 4A, and the first contact 52A is joined to the lower surface of the first coil 51A in the drawing.

The second electrode 5B includes a second coil 51B supported by the second energizing shaft 4B and a second contact 52B connected to the second coil 51B. For example, the second coil 51B is joined to the end of the second energizing shaft 4B, and the second contact 52B is joined to the upper surface of the second coil 51B in the drawing.

The first coil 51A and the second coil 51B can be formed of a metal material containing aluminum as a main component. The first coil 51A and the second coil 51B may be formed of other materials such as oxygen-free copper.

The first contact 52A and the second contact 52B have, for example, a disk shape and face each other. In the present embodiment, the first electrode 5A corresponds to the so-called fixed side electrode, and the second electrode 5B corresponds to the so-called movable side electrode. That is, the first electrode 5A and the second electrode 5B can be brought into contact with each other. In the example of FIG. 1, the open pole state in which the first contact 52A and the second contact 52B are separated from each other is shown. When the second electrode 5B moves toward the first electrode 5A, the first contact 52A and the second contact 52B come into contact with each other, resulting in a closed pole state. The first contact 52A and the second contact 52B can be formed of a material such as copper chrome, but the present invention is not limited to this example.

The shield 6 has, for example, a tubular shape centered on the shaft AX, and surrounds the first electrode 5A and the second electrode 5B. The shield 6 suppresses the metal melt scattered by the arc generated between the first electrode 5A and the second electrode 5B in the open electrode state from adhering to the insulating container 2 and deteriorating the insulating performance of the insulating container 2. The shield 6 has a protrusion 61 that protrudes from the outer peripheral surface toward the insulating container 2. The protrusion 61 is, for example, an annular shape and is joined to the inner peripheral surface 24 of the insulating container 2. The shield 6 can be made of, for example, stainless steel or copper, but is not limited to this example.

The bellows 7 can be expanded and contracted in the direction along the axis AX. One end of the bellows 7 is joined to the second metal fitting 3B. The other end of the bellows 7 is joined to the second energizing shaft 4B via, for example, a cover 8. The other end of the bellows 7 may be directly joined to the second energizing shaft 4B. The cover 8 covers the bellows 7, and prevents the metal melt scattered by the arc from adhering to the bellows 7.

The inside of the insulating container 2 is kept airtight by the first metal fitting 3A, the second metal fitting 3B, the bellows 7, and the cover 8. The pressure inside the insulating container 2 is preferably 1 × 10 ^-2 Pa or less.

In the present embodiment, among the plurality of members constituting the vacuum valve 1, the first member and the second member fixed to each other are connected (joined) by a sintered body of metal nanoparticles instead of a general brazing material. Has been done. For example, as such a combination of the first member and the second member, the insulating container 2 and the first metal fitting 3A, the insulating container 2 and the second metal fitting 3B, the first energizing shaft 4A and the first metal fitting 3A, and the first energizing shaft 4A and 1st coil 51A, 1st coil 51A and 1st contact 52A, 2nd energizing shaft 4B and 2nd coil 51B, 2nd coil 51B and 2nd contact 52B, shield 6 and insulating container 2, bellows 7 and 2nd Examples thereof include a metal fitting 3B, a bellows 7 and a cover 8, a cover 8 and a second energizing shaft 4B. In FIG. 1, reference numerals CP are attached to the joining positions of the candidates of the first member and the second member illustrated here.

Hereinafter, the details of the joint structure using the sintered body will be described by taking the case where the first member is the insulating container 2 and the second member is the second metal fitting 3B as an example. The joining structure described here can be similarly applied to the joining of the other members listed above, or the joining of other members.

FIG. 2 is a cross-sectional view schematically showing a joint structure between the insulating container 2 and the second metal fitting 3B. The insulating container 2 has an end portion 25 facing the second metal fitting 3B. The second metal fitting 3B has a surface to be joined 32 facing the end portion 25.

The sintered body 9 is arranged between the end portion 25 and the surface to be joined 32. The "sintered body" can also be rephrased as, for example, a sintered layer, a bonded body or a bonded layer. When viewed along the axis AX shown in FIG. 1, the sintered body 9 is an annular (circular) extending along the end portion 25. The sintered body 9 is formed by sintering metal nanoparticles, which are nano-order metal particles. For example, as the material of the metal nanoparticles, gold, silver, copper, alloys thereof, silver oxide or copper oxide can be used. The sintered body 9 may be formed by using metal nanoparticles of two or more kinds of materials exemplified here.

The sintered body 9 fills the space between the end portion 25 and the surface to be joined 32. Further, the sintered body 9 has a first outer surface 91 and a second outer surface 92 exposed from the end portion 25 and the surface to be joined 32. The first outer surface 91 is located between the outer peripheral surface 23 of the insulating container 2 and the surface to be joined 32. The second outer surface 92 is located between the inner peripheral surface 24 of the insulating container 2 and the surface to be joined 32.

In the example of FIG. 2, the first outer surface 91 and the outer peripheral surface 23 are aligned, but they may be slightly displaced. Similarly, in the example of FIG. 2, the second outer surface 92 and the inner peripheral surface 24 are aligned, but these may be slightly displaced.

A first metal covering body 10A is arranged on the first corner portion C1 formed by the outer peripheral surface 23 and the surface to be joined 32. A metal second covering body 10B is arranged on the second corner portion C2 formed by the inner peripheral surface 24 and the bonded surface 32. In the following description, when the first covering body 10A and the second covering body 10B are not particularly distinguished, they may be simply referred to as the covering body 10. The "cover" can also be rephrased as, for example, a sealing member or a reinforcing member.

In the example of FIG. 2, both the first covering body 10A and the second covering body 10B have a fillet shape in which the width increases toward the bonded surface 32. However, the cross-sectional shape of the covering body 10 is not limited to this example. When viewed along the axis AX shown in FIG. 1, the first covering body 10A is an annular shape that continuously extends along the first corner portion C1. Similarly, the second covering 10B is an annular shape that extends continuously along the second corner C2. For example, the covering body 10 can be formed of a low melting point alloy containing any of tin, lead and gold as a main component.

The first covering body 10A covers the first outer surface 91. The first covering body 10A also covers a part of the outer peripheral surface 23 and a part of the bonded surface 32. Similarly, the second covering body 10B covers the second outer surface 92. The second covering body 10B also covers a part of the inner peripheral surface 24 and a part of the bonded surface 32.

The thickness T of the sintered body 9 can be, for example, less than 100 μm. To give a specific example, the thickness T is 30 μm. However, the present invention is not limited to this example, and the thickness T may be 100 μm or more. The height H of the covering body 10 is larger than the thickness T (H> T). For convenience of explanation, the thickness T on the order of microns is shown to be large in FIG. 2, but the thickness T may be extremely small compared to the height H and the thickness of the insulating container 2 and the second metal fitting 3B.

Subsequently, a method of manufacturing the vacuum valve 1 will be described.
FIG. 3 is a flowchart showing a part of the manufacturing method of the vacuum valve 1. Here, as an example, it is assumed that the bonding structure of the sintered body 9 and the covering body 10 is applied to all of the bonding position CPs shown in FIG.

After preparing each member constituting the vacuum valve 1, a joining material to be a base of the sintered body 9 is arranged at each joining position CP (step P1). The bonding material used here is, for example, a paste containing the above-mentioned metal nanoparticles in an organic binder. Such a joining material may be arranged (formed, coated, printed) on either one of the first member and the second member to be joined to each other.

After step P1, the bonding material is pre-dried (step P2). Pre-drying can be carried out, for example, by heating the member on which the bonding material is arranged to a temperature of about 100 ° C. in a vacuum atmosphere. If pre-drying is not required, step P2 may be omitted.

After step P2, each member constituting the vacuum valve 1 is temporarily assembled (step P3). As a result, in each combination of the first member and the second member described above, the joining material is arranged between the first member and the second member.

After the step P3, at each joint position CP, the molten material that is the source of the covering body 10 is arranged around the joint material (step P4). Here, for example, a thread-like molten material can be used. That is, the thread-like molten material is wound in the vicinity of the joining material in a single layer or in a double layer or more. As another example, the molten material may be previously arranged (formed, formed) on the first member or the second member by an appropriate method such as plating. In this case, step P4 may be performed before steps P1 to P3.

Here, assuming that the first member and the second member are the insulating container 2 and the second metal fitting 3B, specific examples of steps P1 to P4 will be given. FIG. 4 is a schematic perspective view showing an example of steps P1 to P3. FIG. 5 is a schematic cross-sectional view showing an example of step P4.

In the example of FIG. 4, the bonding material CM which is a paste is arranged on the bonded surface 32 of the second metal fitting 3B. For example, the bonding material CM can be arranged on the surface to be bonded 32 by screen printing. That is, a metal mask having an opening corresponding to the joining position between the insulating container 2 and the second metal fitting 3B is arranged with respect to the bonded surface 32, and the paste-like bonding material CM is placed on the bonded surface 32 through the opening of the metal mask. Deploy.

Then, if necessary, the insulating container 2 is pressed onto the bonding material CM after drying in step P2. As a result, the insulating container 2 and the second metal fitting 3B are temporarily assembled.

In the example of FIG. 5, the filamentous molten material MM is arranged in triplicate with respect to each of the first corner portion C1 and the second corner portion C2. The number of turns of the filamentous molten material MM may be appropriately determined in consideration of the diameter of the molten material MM, the size of the region to be covered by the coated body 10 after melting, and the like. Further, the number of turns of the molten material MM may be different between the first corner portion C1 and the second corner portion C2.

With respect to the other joining positions CP shown in FIG. 1, the joining material and the molten material can be arranged in the same manner as those described with reference to FIGS. 4 and 5. However, the method of arranging the bonding material and the molten material may be different at each bonding position CP.

After step P4, the temporarily assembled assembly is placed in the furnace (step P5). In this assembly, for example, as shown in FIG. 1, each member of the vacuum valve 1 is temporarily assembled.

Then, first, the inside of the furnace is set to the first temperature T1, and the assembly is heated for a predetermined time in a vacuum atmosphere (step P6). The first temperature T1 is a temperature suitable for sintering the metal nanoparticles contained in the bonding material and is lower than the melting point (for example, solid phase line temperature) of the molten material. As an example, the first temperature T1 is 400 ° C. or lower, preferably 200 ° C. or higher and 300 ° C. or lower. By this step, the metal nanoparticles are sintered and the sintered body 9 is formed.

The specific surface area of metal nanoparticles increases as the size decreases. Therefore, in step P6, the surface energy of only the very surface layer of the metal nanoparticles increases to the same level as that of the liquid phase, and the sintering reaction in which adjacent particles are necked and densified progresses remarkably. In general, solid-phase sintering of a metal is performed at a temperature of 70% or more of the melting point, but when the particle size becomes nano-order, the sintering temperature drops remarkably. As a result, sintering proceeds even at a relatively low temperature, and a good bonding state can be obtained.

After step P6, the inside of the furnace is set to the second temperature T2 and the assembly is further heated for a predetermined time in a vacuum atmosphere (step P7). The second temperature T2 is a temperature equal to or higher than the melting point of the molten material (for example, the solidus temperature). That is, the second temperature T2 is higher than the first temperature T1 (T2> T1). By this step, the molten material melts, covers the sintered body 9, and spreads wet along the surfaces of the first member and the second member. When the molten material is subsequently cooled, a fillet-shaped covering 10 as illustrated in FIG. 2 is formed. In step P7 as well, sintering of metal nanoparticles proceeds in the bonding material.

When, for example, a solder containing 95% lead and 5% tin is used as the molten material, its melting point (solid phase temperature) is 300 ° C. The first temperature T1 in this case can be set to a temperature lower than 300 ° C., for example, 250 ° C. Further, the second temperature T2 can be set to a temperature of 300 ° C. or higher, for example, 350 ° C.

From the viewpoint of advancing the sintering of the metal nanoparticles and eliminating the gaps between the particles as much as possible, it is preferable that the heating time at the first temperature T1 in the step P6 is long. On the other hand, from the viewpoint of reducing the reaction between the components of the molten material and the components of the bonding material, it is preferable that the heating time at the second temperature T2 in step P7 is short. Therefore, the time for heating at the first temperature T1 in the step P6 may be longer than the time for heating at the second temperature T2 in the step P7. As an example, the time for heating at the first temperature T1 is 1 to 2 hours, and the time for heating at the second temperature T2 is 10 to 30 minutes.

After the step P7, the vacuum valve 1 is completed through a step of cooling the assembly and the like. In this vacuum valve 1, the sintered body 9 and the covering body 10 are formed at all of the joint position CPs shown in FIG.

In the above manufacturing method, a case where an assembly in which all the members constituting the vacuum valve 1 are temporarily assembled is heated in one step P6 and P7 is illustrated. As another example, after heating in steps P6 and P7 for an assembly in which a part of the members constituting the vacuum valve 1 is temporarily assembled, step P6 is applied to an assembly in which the remaining members are temporarily assembled in this assembly. , P7 may be heated again.

Subsequently, an example of the effect obtained by the vacuum valve 1 and the manufacturing method thereof according to the present embodiment will be described.
Generally, silver wax such as BAg-8 is used for joining the members constituting the vacuum valve. In this case, it is necessary to heat the temporarily assembled assembly at a high temperature of 800 to 900 ° C. for brazing. When the insulating container 2 is made of oxide-based ceramics and the metal fittings 3A and 3B are made of stainless steel, the linear expansion coefficients of these materials are significantly different, so that the insulating container 2 may be brittlely broken. is there. Similar destruction can occur not only in the insulating container 2 and the metal fittings 3A and 3B, but also in other members joined to each other.

Further, in order to suppress this brittle fracture, for example, a stress relaxation ring made of stainless steel may be arranged between the insulating container 2 and the metal fittings 3A and 3B. When the current is cut off in the vacuum valve, the current-carrying shafts 4A and 4B and the electrodes 5A and 5B open at high speed, so that a large impact is generated. This impact is particularly likely to act on the stress relaxation ring. Therefore, the opening speed is generally determined within a range in which the stress relaxation ring is not damaged. Since the current breaking capacity of the vacuum valve depends on the opening speed, the stress relaxation ring contributes to limiting the performance of the vacuum valve.

Further, since it is necessary to withstand a high temperature at the time of brazing, each member constituting the vacuum valve 1 is required to have high heat resistance. Therefore, a lightweight and inexpensive material such as aluminum cannot be selected, the weight of the vacuum valve increases, and the manufacturing cost also increases.

On the other hand, in the present embodiment, each member is joined by the sintered body 9. In this case, as described above, joining can be performed by heating at a relatively low temperature (for example, 400 ° C. or lower). Therefore, brittle fracture due to the difference in linear expansion coefficient between the members to be joined can be suppressed. Further, as shown in FIG. 1, it is possible to adopt a structure that does not use a stress relaxation ring. In this case, the opening speed can be increased to improve the performance of the vacuum valve 1.

Since each member constituting the vacuum valve 1 can be joined at a low temperature, as described above, the first metal fitting 3A, the second metal fitting 3B, the first energizing shaft 4A, the second energizing shaft 4B, the first coil 51A and the second coil 51B Can be formed of a lightweight and inexpensive material such as aluminum. As a result, the weight of the vacuum valve 1 can be reduced and the manufacturing cost can be reduced.

Further, since the heating temperature can be lowered at the time of joining, the time required for heating and subsequent cooling can be shortened, which is also advantageous in the manufacturing process of the vacuum valve 1. As a result, the production efficiency of the vacuum valve 1 is increased, and the manufacturing cost can be reduced from this viewpoint as well.

There is a possibility that some gaps between the original metal nanoparticles remain in the sintered body 9. For example, when the insulating container 2 and the metal fittings 3A and 3B are joined by the sintered body 9, the airtightness inside the insulating container 2 can be reduced if the gap exists.

On the other hand, the vacuum valve 1 according to the present embodiment includes a covering body 10 that covers the outer surface of the sintered body 9. As a result, even when the gap is formed in the sintered body 9, the airtightness at the joint portion between the insulating container 2 and the metal fittings 3A and 3B can be maintained. If the covering body 10 is arranged inside and outside the joint portion as shown in FIG. 2, the airtightness can be further improved.

As shown in FIG. 2, if the covering body 10 has a fillet shape that covers a part of the first member (for example, the insulating container 2) and the second member (for example, the second metal fitting 3B), the impact at the time of opening is alleviated. be able to. Such an effect can be obtained not only at the joint portion between the insulating container 2 and the second metal fitting 3B but also at the joint portion of other members.
In the manufacturing method illustrated in FIG. 3, the sintered body 9 is first formed in step P6, and then the covering body 10 is formed in step P7. As another example, it is also conceivable to simultaneously form the sintered body 9 and the covering body 10 by heating at the second temperature T2 from the beginning. However, in this case, the material contained in the bonding material which is the source of the sintered body 9 and the material contained in the molten material which is the source of the covering body 10 react to generate a brittle compound, and the vacuum valve 1 May reduce the mechanical strength of the.

On the other hand, when the sintered body 9 is first formed at a first temperature T1 in which the molten material does not melt, and then the molten material is melted at a higher temperature second temperature T2, the brittle compound is unlikely to occur. Thereby, the mechanical strength of the vacuum valve 1 can be increased.

As described above, in the vacuum valve 1 according to the present embodiment, various suitable effects can be obtained by improving the joining structure and the manufacturing method of each member.

[Second Embodiment]
The second embodiment will be described. Elements that are the same as or similar to those in the first embodiment are designated by the same reference numerals, and description thereof will be omitted.
FIG. 6 is a schematic cross-sectional view of the vacuum valve 100 according to the second embodiment. The vacuum valve 100 includes an insulating container 110 made of resin instead of the insulating container 2 made of ceramics. Further, the vacuum valve 100 includes an insulating container 110, an insulating resin layer 120 that covers the periphery of the first metal fitting 3A and the second metal fitting 3B.

When each member is joined using the sintered body 9 as described above, the heating temperature during manufacturing can be reduced. Therefore, it is possible to use the insulating container 110 made of a resin material having lower heat resistance than ceramics. As a result, the weight of the vacuum valve 100 can be further reduced and the manufacturing cost can be reduced. The resin material forming the insulating container 110 may be a thermosetting resin or a thermoplastic resin as long as it can withstand heating during production.

The thickness of the insulating container 110 is preferably 7.5 mm or more, for example. As a result, the strength that can withstand the impact at the time of opening or closing the pole is realized, and the permeation of gas in the insulating container 110 can be suitably suppressed. The thickness of the insulating container 110 is preferably 15 mm or less, for example. As a result, the vacuum valve 1 can be miniaturized.

The resin layer 120 can be formed of, for example, an epoxy resin. By providing the resin layer 120, the insulating property between the vacuum valve 100 and the outside can be improved.

If the resin layer 120 is provided around the insulating container made of ceramics, it is necessary to surface-treat the outer peripheral surface of the insulating container with a silane coupling agent or the like so that the two layers do not peel off. On the other hand, when the resin-made insulating container 110 is used, the surface treatment can be omitted because the insulating container 110 and the resin layer 120 are difficult to peel off. In particular, when a thermosetting resin is used as the insulating container 110, the thermosetting resin has a high affinity with other resins, so that the insulating container 110 and the resin layer 120 can be more strongly fixed. This improves the reliability of the vacuum valve 100.

Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other embodiments, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are also included in the scope of the invention described in the claims and the equivalent scope thereof.

For example, in the first embodiment, it is stated that the first metal fitting 3A, the second metal fitting 3B, the first energizing shaft 4A, the second energizing shaft 4B, the first coil 51A and the second coil 51B can be formed of aluminum. However, it is not necessary that all of these members are made of aluminum, and if at least one of them is made of aluminum, the effect of reducing the weight of the vacuum valve 1 and the manufacturing cost can be obtained.

Further, although a plurality of bonding position CPs are shown in FIGS. 1 and 6, it is not necessary to apply the bonding method using the sintered body 9 to all the bonding position CPs. Further, in the joining position CP shown in FIGS. 1 and 6, there may be a joining position in which the sintered body 9 is used for joining but the covering body 10 is not provided.

In the first embodiment, it was stated that a structure without a stress relaxation ring can be adopted according to the configuration of the embodiment. However, this description is not necessarily intended that the vacuum valve 1 does not include a stress relaxation ring. Further, when the vacuum valve 1 is provided with a stress relaxation ring, the ring and the insulating container 2 or the ring and the metal fittings 3A and 3B may be joined by using the sintered body 9.

1,100 ... Vacuum valve, 2,110 ... Insulated container, 3A, 3B ... Metal fittings, 4A, 4B ... Energizing shaft, 5A, 5B ... Electrode, 6 ... Shield, 7 ... Bellows, 8 ... Cover, 9 ... Sintered body 10, ... Cover, 51A, 51B ... Coil, 52A, 52B ... Contact, CP ... Join position.

Claims (10)

A plurality of members including the first member and the second member,
A sintered body of metal nanoparticles connecting the first member and the second member,
A metal covering covering the outer surface of the sintered body exposed from the first member and the second member, and
A vacuum valve equipped with. The covering body covers a part of the first member and the second member together with the outer surface of the sintered body.
The vacuum valve according to claim 1. The coating is made of an alloy containing any of tin, lead and gold as a main component.
The vacuum valve according to claim 1 or 2. The plurality of members include a pair of electrodes that can be brought into contact with each other, an insulating container that houses the pair of electrodes and has an opening, and a metal fitting that closes the opening.
The first member is the insulating container, and the second member is the metal fitting.
The vacuum valve according to any one of claims 1 to 3. The insulating container has an inner peripheral surface, an outer peripheral surface, and an end portion facing the metal fitting.
The metal fitting has a surface to be joined facing the end portion, and the metal fitting has a surface to be joined.
The sintered body is arranged between the end and the surface to be joined.
The covering body is arranged at least one of a first corner portion formed by the outer peripheral surface and the bonded surface and a second corner portion formed by the inner peripheral surface and the bonded surface. Yes,
The vacuum valve according to claim 4. The plurality of members include a pair of electrodes that can be brought into contact with each other and an insulating container that houses the pair of electrodes.
The insulating container is made of a thermosetting resin or a thermoplastic resin.
The vacuum valve according to any one of claims 1 to 3. The plurality of members include a pair of electrodes that can be brought into contact with each other, a pair of energizing shafts that support the pair of electrodes, an insulating container that houses the pair of electrodes and has an opening, and a metal fitting that closes the opening. , Including
Each of the pair of electrodes includes a coil supported by the current-carrying shaft and contacts connected to the coil.
At least one of the coil, the current-carrying shaft, and the metal fitting is made of a metal material containing aluminum as a main component.
The vacuum valve according to any one of claims 1 to 3. A method for manufacturing a vacuum valve including a plurality of members including a first member and a second member.
Placing a bonding material containing metal nanoparticles between the first member and the second member, and
Placing a metal molten material around the joint material and
Sintering the metal nanoparticles to form a sintered body that joins the first member and the second member.
By melting the molten material to form a covering body covering the outer surface of the sintered body exposed from the first member and the second member.
Manufacturing method including. By heating the bonding material at a first temperature lower than the melting point of the molten material, the metal nanoparticles are sintered.
After the metal nanoparticles are sintered, the molten material is melted by heating the molten material at a second temperature higher than the melting point.
The manufacturing method according to claim 8. The time for heating the bonding material at the first temperature is longer than the time for heating the molten material at the second temperature.
The manufacturing method according to claim 9.

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