Vacuum interrupter and manufacturing method of the vacuum interrupter

Abstract

To provide a technique which can be contributed to facilitate a soldering of both of a coil part and a reinforcement part, and to facilitate an obtain of a desired electrode characteristic.SOLUTION: A reinforcement part 6 formed by having a cylinder circumferential wall 60 which has a diameter that is smaller than that of a cylinder coil part 3 onto an inner peripheral side of the coil part 3 is provided at a concentric-like position. In the coil part 3, a plurality of first and second slit holes 31 and 32 having a shape extended to a shaft-core direction so as to be penetrated to a radial direction of the coil part 3 are formed with a predetermined interval to a peripheral direction. The reinforcement part 6 includes: a surface bonding part 61 that is bonded to an inner peripheral surface 30a in the coil part 3; and an annular-shaped groove part 62 that is extended to the peripheral direction in the surface bonding part 61. The groove part 62 has a shape that is opened to a side opposite to the inner peripheral surface 30a. The surface bonding part 61 is soldered to the inner peripheral surface 30a via a soldering material 7 to be provided to the groove part 62.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a vacuum interrupter and a method for manufacturing the same, and more particularly to a technology applicable to various power facilities and the like.

Background Art

[0002] As an example of a vacuum interrupter applied to various power facilities and the like, in a vacuum vessel having an insulating cylindrical body, a pair of electrodes (a fixed electrode and a movable electrode) are provided so as to face each other in the axial direction of the cylindrical body (hereinafter simply referred to as the axial direction as appropriate) and be separable and connectable (hereinafter, the facing direction is simply referred to as the facing direction as appropriate). A pair of current-carrying shafts (leads) are provided in this vacuum vessel so as to support the back side (the side opposite to the facing direction) of each electrode. Further, one of each current-carrying shaft (for example, the movable-side current-carrying shaft 12b described later) is supported inside the vacuum vessel via a bellows that is stretchable in the axial direction.

[0003] According to such a vacuum interrupter, while maintaining the vacuum state inside the vacuum vessel (specifically, the outer peripheral side of the bellows inside the vacuum vessel), one of each current-carrying shaft (the movable-side current-carrying shaft) can be moved in the axial direction. Thereby, the electrodes can be separated and connected according to the movement of the current-carrying shaft, and the contact can be opened and closed.

[0004] In each electrode, for the purpose of easily exhibiting a desired interruption performance and the like, it has generally become common to be configured to have a magnetic field generation function. As an example of this configuration, there is a configuration having a cylindrical coil portion (magnetic field generation coil portion) extending in the axial direction, a contact portion provided on the facing direction side (contact point side) of the coil portion, and an adapter portion that supports the back side (the side opposite to the facing direction) of the coil portion on the current-carrying shaft.

[0005] When opening and closing the contact by separating and contacting each electrode configured as described above, stress (for example, inertial force or mechanical impact force in the axial direction) may be applied to the electrode. Further, since a plurality of slit holes are provided in the coil portion so as to have a magnetic field generation function, the mechanical strength of the electrode and the like tend to be low, and it is also conceivable that desired electrode characteristics (mechanical characteristics, electrical characteristics, etc.) cannot be obtained.

[0006] Therefore, it has been studied to provide a cylindrical reinforcing portion concentrically on the inner peripheral side of the coil portion so as to withstand the stress and obtain desired electrode characteristics.

[0007] Patent Documents 1 to 3 disclose an aspect in which each component of the electrode (coil portion, contact portion, adapter portion, reinforcing portion, etc.; hereinafter, simply referred to as an electrode element as appropriate) is assembled by brazing. In this brazing, for example, when assembling each electrode element so as to have a target electrode shape, a brazing material is disposed between each assembly surface (or in the vicinity of each assembly surface) of two adjacent electrode elements (two electrode elements to be brazed to each other). Then, the brazing material is melted by heating the assembled assembly, and the melted brazing material is infiltrated between the respective assembly surfaces (for example, infiltrated so as to spread widely by capillary action) and then solidified (cooled to solidify). Thereby, it becomes possible to braze each assembly surface.

[0008] In the brazing according to Patent Documents 1 to 3, the location where the brazing material is disposed is not disclosed, but it is considered that the assemblability and assemblability of each electrode element are not impaired. For example, since the reinforcing portion is to be assembled (for example, assembled so as to be fitted) concentrically on the inner peripheral side of the coil portion, it is desirable that the assembly is not hindered.

[0009] In this case, in both the coil part and the reinforcing part, for example, after assembling the two, brazing is performed through a brazing material disposed at a location other than between the two (for example, in Patent Document 3, the end faces indicated by reference numerals 1a, 1b, 5a, and 5b). Specifically, brazing is performed on, for example, the contact part indicated by reference numeral 4 and the adapter part indicated by reference numeral 6 in Patent Document 3).

Prior Art Documents

Patent Documents

[0010]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0011] It is also desirable to assemble the coil part and the reinforcing part to each other by brazing or the like. However, with the brazing material disposed at a location other than between the coil part and the reinforcing part as described above, even if it melts, it is difficult to penetrate between the two (between each assembly surface), sufficient brazing cannot be achieved, and there is a risk that desired electrode characteristics cannot be obtained.

[0012] The present invention has been made in view of such technical problems, and an object thereof is to provide a technique that can contribute to facilitating brazing of both the coil part and the reinforcing part and making it easier to obtain desired electrode characteristics.

Means for Solving the Problems

[0013] The vacuum interrupter and the method for manufacturing a vacuum interrupter according to this invention can contribute to solving the above problems.

[0014] First, one aspect of the vacuum interrupter includes a vacuum vessel having an insulating cylindrical main body, a pair of electrodes provided in the vacuum vessel so as to be movable toward and away from each other in the axial direction of the cylindrical main body, and a pair of current-carrying shafts that support the respective electrodes on the opposite sides of the opposing direction.

[0015] Each of the electrodes includes a cylindrical coil portion extending in the axial direction, a contact portion provided at an opening in the opposing direction in the coil portion, an adapter portion provided on the opposite side of the coil portion in the opposing direction and supported by the current-carrying shaft, and a reinforcing portion having a smaller diameter than the coil portion and concentrically arranged on the inner peripheral side of the coil portion.

[0016] The coil portion is formed with a plurality of slit holes that penetrate in the radial direction of the coil portion and extend in the axial direction at predetermined intervals in the circumferential direction of the coil portion.

[0017] The reinforcing portion has a surface bonding portion that is surface-bonded to the inner peripheral surface of the coil portion on the outer peripheral surface of the reinforcing portion, and an annular groove portion that extends in the circumferential direction at the surface bonding portion.

[0018] The groove portion is shaped to open only on the side facing the inner peripheral surface of the coil portion.

[0019] And the surface bonding portion is brazed to the inner peripheral surface of the coil portion via a brazing material provided in the groove portion.

[0020] Also, the surface bonding portion may be annular and have a diameter expanded outward in the radial direction from the outer peripheral surface of the reinforcing portion.

[0021] Also, the brazing material may be a strip-shaped body provided to extend along the groove portion, and one or more strip-shaped bodies may be provided with respect to the groove portion.

[0022] Further, when the number of steps of the strip body in the axial direction provided in the groove portion is N, the number of steps of the strip body in the radial direction provided in the groove portion is S, the wire diameter of the strip body is φ, the dimension of the groove portion in the axial direction is w1, and the dimension of the groove portion in the radial direction is w2, it may be characterized in that the following formulas (1) and (2) are satisfied. φN < w1 < φ(N + 1) …(1) φS < w2 < φ(S + 1) …(2).

[0023] Further, the strip body may be characterized in that a notch portion having a shape penetrating in the axial direction is formed in a part of the circumferential direction, and the notch portion is elastically deformable so as to expand and contract in the circumferential direction.

[0024] One aspect of the method for manufacturing a vacuum interrupter includes a brazing material arranging step of arranging the brazing material in the groove portion, and a reinforcing portion assembling step of providing and assembling the reinforcing portion on the inner peripheral side of the coil portion. It is characterized by having a melting step of heating and melting the brazing material.

Advantages of the Invention

[0025] As described above, according to the present invention, it is possible to contribute to facilitating brazing of both the coil portion and the reinforcing portion and easily obtaining desired electrode characteristics.

Brief Description of the Drawings

[0026]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Mode for Carrying Out the Invention

[0027] The vacuum interrupter according to the embodiment of the present invention and the manufacturing method of the vacuum interrupter are completely different from a configuration in which brazing is performed through a brazing material simply arranged at a location other than between the coil portion and the reinforcing portion in both the coil portion and the reinforcing portion (hereinafter, simply referred to as the conventional configuration as appropriate).

[0028] That is, in the present embodiment, a surface joining portion that is surface-joined to the inner peripheral surface of the coil portion on the outer peripheral surface of the reinforcing portion, and an annular groove portion that extends in the circumferential direction of the coil portion (hereinafter, simply referred to as the circumferential direction as appropriate) and in which a brazing material can be provided are provided at the surface joining portion. The groove portion has a shape that opens only on the side facing the inner peripheral surface of the coil portion. Then, the surface joining portion of the reinforcing portion is brazed to the inner peripheral surface of the coil portion through the brazing material provided in the groove portion as described above.

[0029] According to the configuration according to the present embodiment as described above, it is possible to braze and assemble both the coil portion and the reinforcing portion to each other so that the assembly of the reinforcing portion to the inner peripheral side of the coil portion is not hindered.

[0030] When changing the conventional configuration, for example, as in the electrode 9 shown in FIGS. 8 and 9 described later, a notch groove 93 for arranging the brazing material 7 is provided at the outer peripheral edge of the opening end surface 92 on the adapter portion 5 side in the reinforcing portion 91. In this case, the brazing material 7 arranged in the notch groove 93 may be melted and penetrate between the assembly surfaces of both the coil portion 3 and the reinforcing portion 91 (between the inner peripheral surface 30a and the outer peripheral surface 60a). However, since the notch groove 93 has a shape with an opening on the adapter portion 5 side, it is also conceivable that most of the melted brazing material 7 flows toward the adapter portion 5 side (for example, flows along the assembly surface of the adapter portion 5), and there is a possibility that both the coil portion 3 and the reinforcing portion 91 cannot be brazed.

[0031] On the other hand, in the case of the configuration according to the present embodiment, since the groove portion provided at the surface joint portion of the reinforcing portion is open only on the side facing the inner peripheral surface of the coil portion, it is possible to suppress the melted brazing material in the groove portion from flowing toward the adapter portion side (for example, flowing along the assembly surface of the adapter portion).

[0032] As a result, it becomes easier to penetrate the brazing material melted in the groove portion between the assembly surfaces of both the coil portion and the reinforcing portion (for example, penetrate so as to spread widely by capillary action). That is, it becomes easier to braze both the coil portion and the reinforcing portion, and it is also possible to contribute to the electrode characteristics.

[0033] As described above, the present embodiment has a configuration in which a groove portion having a shape that is open only on the side facing the inner peripheral surface is provided at the surface joint portion of the outer peripheral surface of the reinforcing portion that is surface-jointed to the inner peripheral surface of the coil portion, and the reinforcing portion and the coil portion are brazed via the brazing material provided in the groove portion. Therefore, it is possible to appropriately apply the common technical knowledge in various fields (such as the vacuum interrupter field, the electrode field, the brazing field, etc.), and make design modifications by appropriately referring to prior art documents, etc. as necessary. An example thereof is given in the following examples.

[0034] In the following embodiments, for example, for the same content, the detailed description is appropriately omitted by using the same reference numerals. Further, FIG. 7 described later is a view in which the fillet 70 formed by the brazing material 7 is exaggeratedly depicted for convenience.

[0035] ≪Embodiment≫ <Main configuration example of vacuum interrupter> Based on FIG. 1, a schematic configuration example of a vacuum interrupter 1A according to an embodiment will be described. In this vacuum interrupter 1A, a vacuum vessel 1 is provided, which is formed by sealing one axial side (fixed side) of an insulating cylindrical main body 10 with a fixed-side flange 1a and the other axial side (movable side) with a movable-side flange 1b.

[0036] In the case of the cylindrical main body 10 shown in FIG. 1, a cylindrical shield (arc shield) 11 that surrounds the outer peripheral sides of the fixed electrode 2a and the movable electrode 2b described later is supported on the inner peripheral side of the cylindrical main body 10.

[0037] At the center of the fixed-side flange 1a, a columnar fixed-side current-carrying shaft 12a is provided so as to extend from the center to the other axial side (in FIG. 1, it extends through from one axial side to the other axial side). A fixed electrode 2a is supported at the end of the fixed-side current-carrying shaft 12a on the other axial side.

[0038] At the center of the movable-side flange 1b, a flange through-hole 13 having a shape that penetrates the center in the axial direction is provided, and a columnar movable-side current-carrying shaft 12b is inserted through the flange through-hole 13 and extends in the axial direction.

[0039] A movable electrode 2b is supported at the end of the movable-side current-carrying shaft 12b on one axial side. Further, one axial side (movable electrode 2b side) of the movable-side current-carrying shaft 12b is supported inside the vacuum vessel 1 of the movable-side flange 1b via a cylindrical bellows 14 that is axially telescopic and coaxially arranged with the movable-side current-carrying shaft 12b.

[0040] The fixed electrode 2a and the movable electrode 2b are provided with slit holes or the like (specific examples include the first slit hole 31, the second slit hole 32, the slit groove 36, and the contact-side slit hole 41, which will be described later) so as to have a magnetic field generation function.

[0041] According to the vacuum interrupter 1A having the above-described configuration, while maintaining the vacuum state inside the vacuum vessel 1 (specifically, on the outer peripheral side of the bellows 14 inside the vacuum vessel 1), the movable-side current-carrying shaft 12b (and the movable electrode 2b) can be moved in the axial direction of the shaft, and according to the movement of the movable-side current-carrying shaft 12b, the movable electrode 2b can be brought into contact with and separated from the fixed electrode 2a.

[0042] Regarding the materials, shapes, etc. of the respective components of the vacuum interrupter 1A, and the processing methods, assembly methods, mounting methods, etc. of the respective components, various modes can be appropriately applied according to the purpose of use of the vacuum interrupter 1A and the like.

[0043] For example, among the respective components of the vacuum interrupter 1A, an insulating material (for example, alumina ceramics) is applied to the cylindrical main body 10, and a metal material (for example, stainless steel (SUS304), oxygen-free copper, titanium) is applied to the others. However, it is preferable to appropriately select them assuming that expansion (thermal expansion) and residual stress may occur during the assembly of the respective components.

[0044] <Main configuration examples of the fixed electrode 2a and the movable electrode 2b> The fixed electrode 2a and the movable electrode 2b are configured to have a magnetic field generation function for the purpose of easily exhibiting a desired interruption performance, etc. As long as the coil portion 3 and the reinforcing portion 6, which will be described later, are brazed among the respective electrode elements of the electrode 2, for example, the modes shown in FIGS. 1 to 6 can be mentioned.

[0045] Note that the fixed electrode 2a and the movable electrode 2b can each apply the same configuration, and hereinafter, they will be collectively and simply referred to as the electrode 2 as appropriate according to the need. Also, regarding the fixed-side current-carrying shaft 12a and the movable-side current-carrying shaft 12b, hereinafter, they will be collectively and simply referred to as the current-carrying shaft 12 as appropriate according to the need.

[0046] The electrodes 2 shown in FIGS. 1 to 6 include a coil portion (magnetic field generating coil portion) 3 having a cylindrical peripheral wall 30 extending in the axial direction, a disc-shaped contact portion 4 provided on the opening end surface 33 on the opposing side (contact point side) in the coil portion 3, and a disc-shaped adapter portion 5 that supports the opening end surface 34 on the back side (opposite side of the opposing direction) in the coil portion 3 through the energization shaft 12. Further, a reinforcing portion 6 having a cylindrical peripheral wall 60 with a smaller diameter than the coil portion 3 is fitted and provided on the inner peripheral side of the coil portion 3 so as to be concentrically positioned.

[0047] The materials, shapes, etc. of each electrode element of the electrode 2, and the processing methods, assembly methods, mounting methods, etc. of each electrode element can also be appropriately applied in various modes according to the purpose of use of the vacuum interrupter 1A, etc. For example, in the coil portion 3, the contact portion 4, and the adapter portion 5, it is preferable to apply a highly conductive metal material, and as an example, oxygen-free copper or the like can be applied. On the other hand, in the reinforcing portion 6, it is preferable to apply a metal material with high mechanical strength, and as an example, stainless steel (SUS304) can be applied.

[0048] <Configuration example of the coil portion 3> The coil portion 3 has a first slit hole 31 that penetrates in the radial direction (hereinafter, simply referred to as the radial direction as appropriate) of the coil portion 3 in the peripheral wall 30 and extends in the axial direction (in the figure, it extends in the so-called Z winding direction along the axis 35), and a shape that opens on the opening end surface 33 side, and a second slit hole 32 that penetrates and extends in the axial direction in the same manner as the first slit hole 31 and opens on the opening end surface 34 side. A plurality of (six each in the figure) of these are alternately formed at predetermined intervals in the circumferential direction of the coil portion 3.

[0049] At the position on the opening side of each first slit hole 31 on the opening end surface 33, slit grooves 36 that penetrate in the radial direction are respectively formed.

[0050] The first slit hole 31, the second slit hole 32, and the slit groove 36 may be formed in any manner as long as they can provide a desired magnetic field generation function, and various embodiments can be applied. In the case of the first slit hole 31 and the second slit hole 32 in the figure, they extend from near the central portion in the axial direction in the coil portion 3 to the respective opening sides (the opening end face 33, 34 sides), and are inclined at an angle (tilt angle) α with respect to the axis 35 of the coil portion 3, but are not limited thereto.

[0051] The angle α can be set as appropriate, and as an example, it can be set within the range of 60° to 80°. Also, the circumferential opening angles of the first slit hole 31, the second slit hole 32, and the slit groove 36 with respect to the axis 35 of the coil portion 3 can also be set as appropriate (for example, set to be constant), and as an example, they can be set within the range of [540 / s]° to [1440 / s]° (s is the total number of the first slit hole 31, the second slit hole 32, and the slit groove 36 respectively).

[0052] Also, in the case of the coil portion 3 in the figure, a surface-to-be-joined portion 30b having a shape that is reduced in diameter inward in the radial direction is formed on the adapter portion 5 side (the portion facing the surface joining portion 61 to be described later) on the inner peripheral surface 30a. Thereby, the coil portion 3 is configured to be easily surface-joined to the outer peripheral surface 60a of the reinforcing portion 6 at the surface-to-be-joined portion 30b of the inner peripheral surface 30a.

[0053] <Configuration example of the contact portion 4> Similar to the coil portion 3, the contact portion 4 can be configured to obtain a desired magnetic field generation function. As a specific example, a contact-side slit hole 41 having a shape that extends in the radial direction through the thickness direction (axial direction) of the contact portion 4 and an opening on the outer side (outer peripheral end face 40 side) in the radial direction is formed at a plurality of positions at predetermined intervals in the circumferential direction of the contact portion 4.

[0054] In the case of each contact-side slit hole 41 in the figure, the inner end portion 42 in the radial direction of the contact-side slit hole 41 is located away from the axis 35, and as it approaches from the inner side to the outer side in the radial direction, it has a shape inclined so as to be biased toward one side in the circumferential direction from the radial direction (in the figure, the clockwise direction when facing from the opposing direction side). Due to each contact-side slit hole 41 having such a shape, as shown in FIG. 5, it has a configuration forming a spiral shape as a whole.

[0055] Also, in the contact portion 4 in the figure, the contact-side slit holes 41 are formed in the same number as the slit grooves 36, and are provided on the opening end surface 33 of the coil portion 3 so that the outer peripheral end surface 40 side (opening side) of the contact-side slit holes 41 faces the slit grooves 36. As a result, the first slit hole 31 and the contact-side slit holes 41 are configured to communicate with each other via the slit grooves 36.

[0056] <Configuration example of the adapter portion 5> The adapter portion 5 may have a configuration that can support the opening end surface 34 on the back side (opposite side of the opposing direction) of the coil portion 3 on the energization shaft 12, and various modes can be applied. For example, in the case of the adapter portion 5 in the figure, the central portion of the adapter portion 5 is configured to be supported by the energization shaft 12.

[0057] Also, in the case of the adapter portion 5 in the figure, it is configured separately from the coil portion 3, but it is not limited to this, and it may be integrally configured with the coil portion 3. In this case, the coil portion 3 and the adapter portion 5 form a bottomed cylindrical structure as a whole.

[0058] <Configuration example of the reinforcing portion 6> In the reinforcing portion 6, on the outer peripheral surface 60a of the peripheral wall 60, a surface bonding portion 61 that is surface-bonded to the inner peripheral surface 30a of the coil portion 3 is formed. Also, at the central portion in the axial direction of the surface bonding portion 61, an annular groove portion 62 extending in the circumferential direction at the central portion is formed, and it is possible to provide a brazing material 7 in the groove portion 62.

[0059] The surface joint portion 61 only needs to be able to be surface-joined to the inner peripheral surface 30a in a state where the reinforcing portion 6 is provided on the inner peripheral side of the coil portion 3, and various modes can be applied. In the case of the reinforcing portion 6 in the figure, an annular surface joint portion 61 that is expanded radially outward is formed at a location on the outer peripheral surface 60a of the peripheral wall 60 that faces the surface to be joined portion 30b on the adapter portion 5 side. The surface joint portion 61 is configured to be easily surface-joined to the surface to be joined portion 30b, but is not limited thereto.

[0060] For example, in the figure, the surface to be joined portion 30b and the surface joint portion 61 are formed so as to face each other only in a partial region in the axial direction on the inner peripheral surface 30a and the outer peripheral surface 60a (the region on the adapter portion 5 side in the figure), but may be formed over the entire axial direction, or may be formed only in the central region in the axial direction or only in the region on the contact portion 4 side in the axial direction.

[0061] The groove portion 62 has a shape that opens only on the side facing the inner peripheral surface 30a of the coil portion 3, and the inner side in the radial direction and the axial direction side of the groove portion 62 are shielded by the groove inner wall surface 63.

[0062] In the groove portion 62, it has a shape that opens only on the side facing the inner peripheral surface 30a of the coil portion 3 as described above, and as long as a desired brazing material 7 can be arranged, various modes can be applied. In the case of the groove portion 62 in the figure, the shape of the groove inner wall surface 63 in the cross-sectional direction (axial direction) is U-shaped, but may be other shapes such as C-shaped or V-shaped.

[0063] <Configuration Example of Brazing Material 7> The brazing material 7 can be provided so as to extend along the circumferential direction with respect to the groove portion 62 so as not to prevent the assembly of the reinforcing portion 6 with respect to the inner peripheral side of the coil portion 3. As long as the brazing material 7 provided in the groove portion 62 can be melted and then solidified to braze the coil portion 3 and the reinforcing portion 6, various modes can be applied.

[0064] For example, when the coil part 3 is made of oxygen-free copper and the reinforcing part 6 is made of stainless steel, a brazing material 7 with a melting point lower than that of the oxygen-free copper can be applied. As an example, an Ag-based (such as Ag-Cu-based) one can be applied.

[0065] Also, for example, when a long linear brazing material product that can be plastically deformed by bending or the like is applied as the brazing material 7, it can be formed into a molded body (hereinafter simply referred to as a linear body as appropriate) that extends along the groove part 62 and then applied. As a specific example, a linear body formed by winding the brazing material product along the groove part 62 (for example, winding and forming within a range of one turn or less with respect to the groove part 62) can be applied, or a linear body obtained by previously forming the brazing material product can be fitted into the groove part 62 and provided.

[0066] The brazing material 7 in the form of the above-mentioned linear body may be provided simply as one (one stage in the axial direction) as shown in FIG. 6(A) for example, or may be provided as a plurality (in FIG. 6(B), two stages in the axial direction) as shown in FIG. 6(B).

[0067] Also, the brazing material product may be wound spirally along the groove part 62 and wound (wound a predetermined number of turns), whereby such a spiral linear body will be formed. When forming such a spiral linear body, every time one turn with respect to the groove part 62 is completed and the next turn starts to be wound, the number of stages in the axial direction by the linear body will increase by one stage each time.

[0068] Also, the brazing material product may be wound in a spiral shape along the groove part 62 and wound (wound a predetermined number of turns), whereby such a spiral-shaped linear body will be formed. When forming such a spiral-shaped linear body, every time one turn with respect to the groove part 62 is completed and the next turn starts to be wound, the number of stages in the radial direction by the linear body will increase by one stage each time.

[0069] When applying the brazing material 7 with striations as shown above, it is necessary to appropriately design it so as to satisfy the following formulas (1) and (2). Here, let the number of axial stages of the striations provided in the groove portion 62 be N, the number of radial stages of the striations provided in the groove portion 62 be S, the wire diameter of the striations be φ, the groove width dimension (axial dimension) of the groove portion 62 be w1, and the depth dimension (radial dimension) of the groove portion 62 be w2. φN < w1 < φ(N + 1) …(1) φS < w2 < φ(S + 1) …(2).

[0070] By appropriately designing so as to satisfy these formulas (1) and (2), it becomes easier to accommodate the entire brazing material 7 with striations within the groove portion 62, and it can be suppressed so as not to hinder the assembly of the reinforcing portion 6 with respect to the inner peripheral side of the coil portion 3. Further, an appropriate surplus space 64 can also be provided between the brazing material 7 provided in the groove portion 62 and the groove inner wall surface 63. In this case, there is a possibility that the brazing material 7 can be easily arranged with respect to the groove portion 62.

[0071] The brazing material 7 may have a structure with appropriate elasticity (elasticity to the extent that it does not plastically deform). Thereby, it is also possible to fit and provide it in the groove portion 62 in a snap fit manner. Specifically, in the case of the brazing material 7 in the figure, a notch portion 71 having a shape penetrating in the axial direction is formed in a part of the circumferential direction of the brazing material 7.

[0072] In the case of such a brazing material 7, after being elastically deformed and expanded in diameter so that the notch portion 71 extends in the circumferential direction and arranged concentrically with respect to the outer peripheral side of the groove portion 62, by elastically restoring the brazing material 7, it becomes possible to fit and provide it in the groove portion 62. Further, in the brazing material 7, for example, it can be suppressed so as not to separate from the groove portion 62.

[0073] When a plurality of brazing materials 7 having notches 71 are provided, it is preferably set as appropriate so that the notches 71 of the respective brazing materials 7 do not overlap in the axial direction. For example, in the case of the notches 71 of the two brazing materials 7 in FIG. 6(B), it can be set so as to be positioned opposite to each other in the radial direction (for example, set so as to be positioned on the front side and the depth side shown in FIG. 6(B)).

[0074] In addition, when the brazing material 7 made of a strip cannot be arranged as desired with respect to the groove portion 62, for example, a part of the brazing material 7 may protrude outward from the opening of the groove portion 62 (hereinafter, simply referred to as a protruding state as appropriate). Such a protruding state of the brazing material 7 can be recognized, for example, when an operator is performing an assembling operation of the reinforcing portion 6 with respect to the inner peripheral side of the coil portion 3, and the inner peripheral surface 30a and the opening end surface 33 of the coil portion 3 collide with the protruding portion of the brazing material 7.

[0075] When the protruding state of the brazing material 7 is recognized, the assembling operation is stopped, and the cause of the protruding state is eliminated (for example, correction or replacement of the distortion of the strip, change of the number of stages in the axial direction or the radial direction of the strip, or review of the assembling operation, etc.), and then the assembling operation is performed again.

[0076] In addition, when the brazing material 7 has elasticity or a surplus space 64 is formed as described above, even if the inner peripheral surface 30a and the opening end surface 33 of the coil portion 3 collide with the protruding portion of the brazing material 7 during the assembling operation, the assembling operation can be continued while further pressing appropriately, and thus there is a sufficient possibility that the entire brazing material 7 is accommodated in the groove portion 62.

[0077] <An example of the assembling method of each electrode element> Each electrode element of the electrode 2 can be assembled and assembled while appropriately using a brazing material. However, for the assembly of the reinforcing portion 6 with respect to the inner peripheral side of the coil portion 3, the following brazing material arrangement process, assembly process, and melting process can be performed in order.

[0078] First, in the brazing material placement step, in the reinforcing portion 6, for example, as shown in FIG. 6, the brazing material 7 is provided in the groove portion 62. Then, in the assembly step, the reinforcing portion 6 is fitted and provided so as to be concentrically positioned with respect to the inner peripheral side of the coil portion 3. Thus, for example, as shown in FIG. 3, the coil portion 3 and the reinforcing portion 6 are assembled, and an assembly in which the surface joining portion 61 and the surface to be joined portion 30b are surface-joined can be obtained.

[0079] Next, in the melting step, for example, by disposing the assembly in a heating furnace or the like, the brazing material 7 is heated to a molten state. The molten brazing material 7 penetrates between the surface joining portion 61 and the surface to be joined portion 30b (between the respective assembly surfaces), for example, by capillary action, and then cools down and solidifies. As a result, the surface joining portion 61 and the surface to be joined portion 30b are brazed.

[0080] Among the reinforcing portions 6 assembled to the inner peripheral side of the coil portion 3 as described above, with respect to the portions facing the first slit hole 31 and the second slit hole 32 of the coil portion 3, they can be observed through the first slit hole 31 and the second slit hole 32, respectively.

[0081] For example, when observing the inner side in the radial direction of the second slit hole 32 from the outside, it is also possible to observe the surface joining portion 61 and the groove portion 62 of the reinforcing portion 6 as shown in FIG. 8(A) described later.

[0082] <Verification Example> Next, a plurality of electrodes 2 were fabricated based on the examples, and the assemblability (brazing property) of both the coil portion 3 and the reinforcing portion 6 was evaluated by the methods shown below. As comparative examples, a plurality of electrodes 9 shown in FIGS. 8 and 9 were also fabricated, and the assemblability was evaluated in the same manner as for the electrode 2.

[0083] First, in the six second slit holes 32 formed in the coil portion 3 of each electrode 2, observation was made so that the inner side in the radial direction faced from the outside. As a result, in almost all of the second slit holes 32 of each electrode 2, it was observed that a fillet 70 by the brazing material 7 was formed as shown in FIG. 7(A). Further, both the coil portion 3 and the reinforcing portion 6 of each electrode 2 were cut along the axis 35, and observation was made between both the surface joint portion 61 and the surface to be joined portion 30b through the cut surface. As a result, it was confirmed that the brazing material 7 penetrated so as to widely spread between both of them and was brazed as desired.

[0084] On the other hand, in each electrode 9, when observation was made through each second slit hole 32 in the same manner as in the case of the electrode 2, in some of the second slit holes 32, a fillet 70 by the brazing material 7 was slightly formed as shown in FIG. 7(B) in some cases, but in most of the second slit holes 32, the fillet 70 could not be observed. Further, both the coil portion 3 and the reinforcing portion 6 of each electrode 9 were cut along the axis 35, and observation was made between both the surface joint portion 94 and the surface to be joined portion 30b through the cut surface. As a result, it was confirmed that the brazing was insufficient as compared with the case of the electrode 2.

[0085] Therefore, according to the embodiment, it was found that the electrode 2 can be formed by brazing both the coil portion 3 and the reinforcing portion 6 as desired, and desired electrode characteristics can be easily obtained.

[0086] As described above, in the present invention, although detailed description has been made only for the specific examples described, it is obvious to those skilled in the art that various changes and the like are possible within the scope of the technical idea of the present invention, and it is natural that such changes and the like belong to the scope of the claims.

Explanation of Reference Numerals

[0087] 1A... Vacuum interrupter 2a... Fixed electrode, fixed-side energization shaft 12a 2b... Movable electrode, movable-side energization shaft 12b 3…Coil part, 30a…Inner wall surface, 30b…Cover surface joint part, 31…First slit hole, 32…Second slit hole, 36…Slit groove 4…Contact part 5…Adapter part 6…Reinforcement part, 61…Surface joint part, 62…Groove part, 63…Groove inner wall surface, 64…Surplus space 7…Solder material, 71…Notch part

Claims

1. A vacuum vessel having an insulating cylindrical body, A pair of electrodes provided in the vacuum vessel so as to be movable toward and away from each other in the axial direction of the cylindrical body, A pair of current-carrying shafts that support the respective electrodes on the opposite side of the facing direction, Comprising: Each of the electrodes, A cylindrical coil portion extending in the axial direction, A contact portion provided at an opening in the facing direction in the coil portion, An adapter portion provided on the opposite side of the coil portion in the facing direction and supported by the current-carrying shaft, A reinforcing portion having a cylindrical shape with a smaller diameter than the coil portion and concentrically arranged on the inner peripheral side of the coil portion, Having: The coil portion has a plurality of slit holes formed at predetermined intervals in the circumferential direction, the slit holes having a shape that penetrates in the radial direction of the coil portion and extends in the axial direction, The reinforcing portion, A surface bonding portion that is surface-bonded to the inner peripheral surface of the coil portion on the outer peripheral surface of the reinforcing portion, An annular groove portion extending in the circumferential direction at the surface bonding portion, Having: The groove portion is open only on the side facing the inner peripheral surface of the coil portion, The surface bonding portion is brazed to the inner peripheral surface of the coil portion via a brazing material provided in the groove portion. A vacuum interrupter characterized by this.

2. The vacuum interrupter according to claim 1, wherein the surface bonding portion is an annular shape that expands in diameter outward in the radial direction from the outer peripheral surface of the reinforcing portion.

3. The brazing material is a strip-shaped body provided so as to extend along the groove portion, The vacuum interrupter according to claim 1, wherein one or more of the strip-shaped bodies are provided with respect to the groove portion.

4. When the number of steps in the axial direction of the strip-shaped body provided in the groove portion is N, the number of steps in the radial direction of the strip-shaped body provided in the groove portion is S, the wire diameter of the strip-shaped body is φ, the dimension in the axial direction of the groove portion is w1, and the dimension in the radial direction of the groove portion is w2, the vacuum interrupter according to claim 3, characterized by satisfying the following formulas (1) and (2). φN < w1 < φ(N + 1) …(1) φS < w2 < φ(S + 1) …(2).

5. The vacuum interrupter according to claim 3, wherein the strip-shaped body has a notch portion formed in a part of the circumferential direction and having a shape that penetrates in the axial direction, and the notch portion is elastically deformable so as to expand and contract in the circumferential direction.

6. A method for manufacturing a vacuum interrupter according to any one of claims 1 to 5, a brazing material placement step of placing the brazing material in the groove portion, a reinforcing portion assembly step of providing and assembling the reinforcing portion on the inner peripheral side of the coil portion, a melting step of heating and melting the brazing material, characterized by comprising the above steps.

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