Electrode structure, vacuum interrupter

Abstract

To provide a technology capable of facilitating contributing to both suppression of resistance loss in a coil portion etc. and increase of magnetic flux density.SOLUTION: In a coil part 3 of each electrode 2, multiple first slit holes 31 and second slit holes 32 which have a shape extending in the Z winding direction are formed alternately in the circumferential direction of the coil part 3. In a contact part 4, multiple third slit holes 41 which each extend radially outward from an axis 35 side and which are each open on the radially outer side such that a third slit open end is formed are formed in the circumferential direction. The third slit holes 41 each have an arc shape which bends in the clockwise direction in a view from the opposite direction. A third slit closed end 41b of each third slit hole 41 is positioned to be separated from the axis of the contact part 4 radially outward thereof and is positioned opposite from the first slit open end 31a. A third slit open end 41a of one of the electrodes 2 and a third slit open end 41a of the other of the electrodes 2 are opposite each other in the axis direction.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an electrode structure and a vacuum interrupter, and relates to a technique that can be applied to, for example, various electric power facilities. [Background technology]

[0002] For example, one example of a vacuum interrupter used in various electric power facilities has a configuration in which a pair of electrodes (a fixed electrode and a movable electrode) are provided in a vacuum vessel having an insulating cylindrical body, facing each other (hereinafter, the facing direction will be referred to simply as the facing direction) in the axial direction of the cylindrical body (hereinafter, simply referred to as the axial direction), so that they can be freely connected and disconnected. This vacuum vessel is provided with a pair of current-carrying shafts (leads) that support the back sides (opposite the facing direction) of each electrode. Furthermore, one of the current-carrying shafts (for example, the movable current-carrying shaft 12b described below) is supported inside the vacuum vessel via a bellows that is expandable and contractible in the axial direction.

[0003] With a vacuum interrupter configured as described above, one of the current-carrying shafts (the movable current-carrying shaft) can be moved axially while maintaining a vacuum state inside the vacuum vessel (specifically, on the outer periphery of the bellows inside the vacuum vessel), thereby making it possible to connect and disconnect the electrodes and open and close the contacts in accordance with the movement of the current-carrying shaft.

[0004] Each electrode is generally configured to have a magnetic field generating function in order to facilitate the desired breaking performance, etc. One example of this configuration includes a cylindrical coil portion (magnetic field generating coil portion) extending in the axial direction, a contact portion provided on the opposing side (contact side) of the coil portion, and an adapter portion that supports the back side (opposite side of the opposing direction) of the coil portion on a current-carrying shaft (for example, Patent Documents 1 to 4).

[0005] When the electrodes of this configuration are brought into contact with or separated from each other to open or close the contacts, stress (such as axial inertial force or mechanical impact force) may be applied to the electrodes. Since the coil and contact sections have multiple slits to generate a magnetic field, the mechanical strength of the electrodes is likely to be reduced. As a result, it may be difficult to maintain the desired electrode characteristics (mechanical characteristics, electrical characteristics, etc.).

[0006] In the future, as vacuum interrupters are designed to operate at higher voltages and have larger capacities, the opening and closing speed of the contacts will increase and the operating force required for opening and closing the contacts will likely increase, which could result in greater stresses as described above.

[0007] Therefore, it has been considered to provide a cylindrical reinforcing portion concentrically on the inner periphery of the coil portion so that the electrode can withstand the stress and easily maintain the desired electrode characteristics. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-086068 [Patent Document 2] Japanese Patent Application Laid-Open No. 2003-086067 [Patent Document 3] Japanese Patent Application Laid-Open No. 2003-151413 [Patent Document 4] Japanese Patent Application Publication No. 2018-181681 Summary of the Invention [Problem to be solved by the invention]

[0009] It is desirable to suppress the resistance loss (heat generation) of the coil portion of each electrode when, for example, a rated current is passed through it. However, if slit holes are provided in the coil portion as described above, the current-carrying cross-sectional area of ​​the coil portion is likely to become small, which may make it difficult to suppress the resistance loss.

[0010] For example, if the thickness of the coil portion in the radial direction (hereinafter simply referred to as the radial direction) is increased, the current-carrying cross-sectional area of ​​the coil portion also increases, which may make it easier to suppress resistance loss. However, this may reduce the magnetic flux density (hereinafter simply referred to as the magnetic flux density) of the magnetic field that can be generated between the electrodes (when current is interrupted), which may make it difficult to obtain the desired interruption performance.

[0011] From the above viewpoint, it is desired not only to suppress the resistance loss of the coil portion, etc., but also to increase the magnetic flux density.

[0012] The present invention has been made in consideration of such technical challenges, and aims to provide a technology that can easily contribute to both suppressing resistance loss in coil sections, etc. and increasing magnetic flux density. [Means for solving the problem]

[0013] The electrode structure and vacuum interrupter according to the present invention can contribute to solving the above problems.

[0014] First, one aspect of the electrode structure comprises a pair of electrodes arranged in a vacuum vessel having an insulating cylindrical body, facing each other in the axial direction of the cylindrical body and capable of moving toward and away from each other, and a pair of conductive shafts supporting each of the electrodes on opposite sides of the facing direction.

[0015] Each electrode has a cylindrical coil portion extending in the axial direction, a contact portion provided at an opening on the opposing side of 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 that is cylindrical and has a smaller diameter than the coil portion and is arranged concentrically on the inner side of the coil portion.

[0016] The coil portion has a first slit hole that has a shape that penetrates the coil portion in the radial direction and a shape that extends from the center of the coil portion in the axial direction in the Z-winding direction toward the opposing direction, and has a first slit opening end that opens in the opposing direction, and a second slit hole that has a shape that penetrates the coil portion in the radial direction and a shape that extends from the center of the coil portion in the axial direction in the Z-winding direction toward the opposite side of the opposing direction, and has a second slit opening end that opens on the opposite side of the opposing direction, and is formed alternately at a predetermined interval around the coil portion.

[0017] The contact portion has a shape that penetrates in the axial direction and a shape that extends radially outward from the axial side of the contact portion, and a plurality of third slit holes that open radially outward and have third slit opening ends formed therein are formed at predetermined intervals in the circumferential direction.

[0018] Each of the third slit holes has an arc shape curved in a clockwise direction when viewed from the opposing side, and the third slit closed end, which is opposite the third slit opening end of the third slit hole, is located away from the axis of the contact portion radially outward, and the third slit opening end is located opposite the first slit opening end.

[0019] The third slit opening end of one of the electrodes and the third slit opening end of the other of the electrodes are opposed to each other in the axial direction.

[0020] Each electrode may be characterized in that it satisfies the following equations (1) and (2) when the radius of the contact portion is R0, the radius of curvature of the third slit hole is Rs, the distance between the axis of the contact portion and the closed end of the third slit is R1, and the distance between the axis of the contact portion and the center point of curvature of the third slit hole is R2. Rs>R0-R2…(1) |R1-R2|≧Rs>(R1+R2)×0.7…(2).

[0021] The first slit opening edge surface may be formed with a first slit groove that penetrates in the radial direction.

[0022] The adapter portion may also be characterized in that it has a shape that penetrates in the axial direction and a shape that extends radially outward from the axial side of the adapter portion, and that a plurality of fourth slit holes that open radially outward and have fourth slit opening ends formed therein are formed at predetermined intervals in the circumferential direction, and the fourth slit opening ends are positioned opposite the second slit opening ends.

[0023] The second slit groove may be formed in an opening edge surface of the second slit opening end portion, the second slit groove having a shape penetrating in the radial direction.

[0024] One aspect of the vacuum interrupter is characterized by having any one of the above electrode structures. [Effects of the Invention]

[0025] As described above, according to the present invention, it is possible to easily contribute to both suppressing resistance loss in the coil portion and increasing magnetic flux density. [Brief explanation of the drawings]

[0026] [Figure 1] 1 is a schematic diagram (axial longitudinal cross-sectional view) illustrating the schematic configuration of a vacuum interrupter 1A according to an embodiment. [Figure 2] 2 is a schematic diagram (perspective view) illustrating the schematic configuration of electrodes 2 (fixed electrode 2a, movable electrode 2b) of the vacuum interrupter 1A shown in FIG. 1. FIG. [Figure 3] 3 is a schematic diagram (partial vertical cross-sectional view in the axial direction) illustrating the schematic configuration of the electrode 2 (fixed electrode 2a, movable electrode 2b) shown in FIG. 2. FIG. [Figure 4] 3 is a schematic diagram (perspective view) illustrating the schematic configuration of the coil portion 3 of the electrode 2 (fixed electrode 2a, movable electrode 2b) shown in FIG. 2. FIG. [Figure 5] 5A and 5B are schematic diagrams illustrating the general configuration of the contact portion 4 of the electrode 2 (fixed electrode 2a, movable electrode 2b) shown in FIG. 2 ((A) is a perspective view, and (B) is a view viewed from the opposite side of the opposing direction of the electrode 2a (the upper side in FIG. 5A)). [Figure 6] Figures showing the simulation analysis results of the current density distribution and current vectors for analytical models M0 and M2 ((A) is for model M0, (B) is for model M2). [Figure 7] FIG. 10 is a characteristic diagram showing the simulation analysis results of the longitudinal magnetic flux density of analytical models M0 and M1 to M3. DETAILED DESCRIPTION OF THE INVENTION

[0027] The electrode structure and vacuum interrupter according to the embodiments of the present invention are completely different from configurations (hereinafter simply referred to as conventional configurations) in which slit holes are provided in the coil section, contact section, etc. to simply provide a magnetic field generation function, such as the pair of electrodes provided inside the vacuum container in Patent Documents 1 to 4.

[0028] That is, each electrode in this embodiment has a shape that penetrates radially in the coil portion and extends in the Z-winding direction from the center of the axial direction of the coil portion toward the opposing direction, and is provided with a first slit hole that opens in the opposing direction and has a first slit opening end formed therein.

[0029] In addition, a second slit hole is provided which has a shape that penetrates the coil portion in the radial direction and a shape that extends in the Z-winding direction from the center of the coil portion in the axial direction to the opposite side of the opposing direction, and which opens to the opposite side of the opposing direction and has a second slit opening end formed therein.

[0030] A plurality of these first slit holes and second slit holes are formed alternately at predetermined intervals in the circumferential direction of the coil portion (hereinafter simply referred to as the circumferential direction).

[0031] In the contact portion, a plurality of third slit holes are formed at predetermined intervals in the circumferential direction, each of which has a shape penetrating in the axial direction and a shape extending radially outward from the axial side of the contact portion, and which open radially outward and have a third slit opening end formed therein.

[0032] Each third slit hole has an arc shape curved in a clockwise direction when viewed from the opposing side, and the third slit closed end, which is opposite the third slit open end of the third slit hole, is located radially outward from the axis of the contact portion, and the third slit open end is located opposite the first slit open end.

[0033] The third slit opening end of one of the electrodes and the third slit opening end of the other of the electrodes are opposed to each other in the axial direction.

[0034] According to this embodiment, the current path of each electrode is formed along the first slit, the second slit, and the third slit, respectively, which means that the current flowing through each electrode tends to flow in the circumferential direction (for example, the Z-winding direction in the coil portion).

[0035] Furthermore, since the third slit opening end of one of the electrodes and the third slit opening end of the other of the electrodes face each other in the axial direction and each third slit hole is arc-shaped, it is easier to form a long current path for each electrode compared to, for example, a conventional configuration (where the third slit hole is simply linear in shape).

[0036] Therefore, according to this embodiment, it is relatively easy to obtain a desired magnetic flux density even when, for example, the current-carrying cross-sectional area of ​​the coil is increased to suppress resistance loss. In other words, compared to the conventional configuration, this embodiment is more likely to contribute to both suppressing resistance loss in the coil and increasing magnetic flux density, and may make it easier to obtain desired breaking performance.

[0037] As described above, this embodiment has a configuration in which a current path is formed along the first slit hole, the second slit hole, and the third slit hole of each electrode, and the third slit opening end of one of the electrodes and the third slit opening end of the other of the electrodes face each other in the axial direction, and each third slit hole has an arc shape. Therefore, it is possible to appropriately apply common technical knowledge in various fields (vacuum interrupter field, electrode field, magnetic field field, etc.) and appropriately refer to prior art documents as necessary to modify the design, and the following examples are given as examples.

[0038] In the following embodiments, detailed descriptions will be omitted as appropriate, for example, by referring to the same reference numerals for similar contents.

[0039] Example <Examples of main configurations of vacuum interrupters> An example of the schematic configuration of a vacuum interrupter 1A according to an embodiment will be described with reference to Figure 1. This vacuum interrupter 1A includes a vacuum vessel 1 having an insulating cylindrical body 10 whose one axial side (fixed side) is sealed with a fixed flange 1a and whose other axial side (movable side) is sealed with a movable flange 1b.

[0040] In the case of the cylindrical main body 10 shown in Figure 1, a cylindrical shield (arc shield) 11 surrounding the outer periphery of the fixed electrode 2a and the movable electrode 2b described below is supported on the inner periphery of the cylindrical main body 10.

[0041] A columnar fixed-side current-carrying shaft 12a is provided at the center of the fixed-side flange 1a so as to extend from the center to the other axial side (extending from one axial side to the other axial side in FIG. 1). The fixed electrode 2a is supported at the end of the fixed-side current-carrying shaft 12a on the other axial side.

[0042] A flange through hole 13 is provided in the center of the movable side flange 1b, and extends axially through the center. A columnar movable side current-carrying shaft 12b is inserted into the flange through hole 13 and extends axially.

[0043] The movable electrode 2b is supported at one axial end of the movable current-carrying shaft 12b. The one axial end of the movable current-carrying shaft 12b (the movable electrode 2b side) is supported inside the vacuum vessel 1 of the movable flange 1b via a cylindrical bellows 14 that is axially expandable and contractible and is arranged coaxially with the movable current-carrying shaft 12b.

[0044] The fixed electrode 2a and the movable electrode 2b are provided with slit holes etc. (specific examples include the first slit hole 31, the second slit hole 32, the first slit groove 31b, the second slit groove 32b, the third slit hole 41, and the fourth slit hole 51, which will be described later) to have a magnetic field generating function.

[0045] According to the vacuum interrupter 1A configured as described above, the movable side current-carrying shaft 12b (and the movable electrode 2b) can be moved in the axial direction while maintaining the vacuum state inside the vacuum vessel 1 (specifically, the outer periphery of the bellows 14 inside the vacuum vessel 1), and the movable electrode 2b can be moved toward or away from the fixed electrode 2a in accordance with the movement of the movable side current-carrying shaft 12b.

[0046] The materials, shapes, etc. of each component of the vacuum interrupter 1A, as well as the processing methods, assembly methods, and mounting methods of each component, can be appropriately applied in various ways depending on the intended use of the vacuum interrupter 1A, etc.

[0047] For example, among the components of the vacuum interrupter 1A, an insulating material (e.g., alumina ceramics) may be used for the cylindrical body 10, and a metal material (e.g., stainless steel (SUS304), oxygen-free copper, titanium) may be used for the other components. However, it is preferable to select the appropriate material taking into account the possibility of expansion (thermal expansion) and residual stress occurring when assembling the components.

[0048] <Main configuration examples of the fixed electrode 2a and the movable electrode 2b> The fixed electrode 2a and the movable electrode 2b may be configured to have a magnetic field generating function for the purpose of facilitating the desired blocking performance, and may be configured in the manners shown in FIGS. 1 to 5, for example.

[0049] The fixed electrode 2a and the movable electrode 2b may have the same configuration, and hereinafter, as needed, they will be collectively referred to simply as the electrode 2. Furthermore, the fixed-side current-carrying shaft 12a and the movable-side current-carrying shaft 12b will hereinafter, as needed, be collectively referred to simply as the current-carrying shaft 12.

[0050] 1 to 5 includes a coil section (magnetic field generating coil section) 3 having a cylindrical peripheral wall 30 extending in the axial direction, a disk-shaped contact section 4 provided at an open end face 33 on the opposing side (contact side) of the coil section 3, and a disk-shaped adapter section 5 that supports an open end face 34 on the back side (opposite the opposing direction) of the coil section 3 on a current-carrying shaft 12. Also, a reinforcing section 6 having a cylindrical peripheral wall 60 with a smaller diameter than the coil section 3 is fitted concentrically around the inner periphery of the coil section 3.

[0051] The material, shape, etc. of each electrode element of electrode 2, as well as the processing method, assembly method, and installation method of each electrode element, can be suitably applied in various modes depending on the intended use of vacuum interrupter 1A. For example, it is preferable to use a metal material with high conductivity, such as oxygen-free copper, for coil portion 3, contact portion 4, and adapter portion 5. On the other hand, it is preferable to use a metal material with high mechanical strength, such as stainless steel (SUS304), for reinforcing portion 6.

[0052] Furthermore, the electrode elements may be assembled using a brazing material, etc. For example, if the coil portion 3 is made of oxygen-free copper and the reinforcing portion 6 is made of stainless steel, a brazing material 7 having a melting point lower than that of the oxygen-free copper may be used. For example, an Ag-based material (such as an Ag-Cu-based material) may be used.

[0053] <Configuration example of coil section 3> The coil portion 3 has a first slit hole 31 formed therein, which penetrates the peripheral wall 30 in the radial direction and extends in the Z-winding direction (in the drawing, the Z-winding direction along the axis 35 of the electrode 2) from the central portion in the axial direction of the peripheral wall 30 toward the opposing direction. The first slit hole 31 has a first slit opening end 31a formed therein, which opens toward the opposing direction.

[0054] A first slit groove 31b is formed in the opening edge surface of the first slit opening end 31a, penetrating in the radial direction, so that the opening diameter of the first slit opening end 31a is expanded in the circumferential direction.

[0055] The coil portion 3 is also formed with a second slit hole 32 that penetrates the peripheral wall 30 in the radial direction and extends in the Z-winding direction from the central portion of the peripheral wall 30 in the axial direction toward the opposite side of the facing direction. The second slit hole 32 is formed with a second slit opening end 32a that opens toward the opposite side of the facing direction.

[0056] A second slit groove 32b is formed in the opening edge surface of the second slit opening end 32a, penetrating in the radial direction, so that the opening diameter of the second slit opening end 32a is expanded in the circumferential direction.

[0057] A plurality of first slit holes 31 and a plurality of second slit holes 32 (six of each in the drawing) are formed in the peripheral wall 30, alternately spaced at predetermined intervals in the circumferential direction.

[0058] The first slit hole 31, the second slit hole 32, the first slit groove 31b, and the second slit groove 32b shown above may be formed in various ways so long as they are capable of achieving the desired magnetic field generation function.

[0059] In the case of the first slit hole 31 and the second slit hole 32 in the figure, they have a shape that extends from near the center of the axial direction of the coil section 3 to each opening side (first slit opening end 31a, second slit opening end 32a), and are inclined at an angle (inclination angle) α with respect to the axial center 35 of the electrode 2 (coil section 3), but are not limited to this.

[0060] The angle α can be set appropriately, and one example thereof is to set it within a range of 60 to 80. Furthermore, as an example of setting the circumferential slit shape (dimension) of each of the first slit holes 31, the second slit holes 32, the first slit grooves 31b, and the second slit grooves 32b, the circumferential azimuth angle formed by the slit shape when viewed from the axis 35 (the angle formed between one end and the other end of the slit shape in the circumferential direction; hereinafter, referred to as the slit azimuth angle) can be set.

[0061] It should be noted that if the slit azimuth angle is too small (i.e., if the circumferential dimension of the slit shape is short), it may be difficult to obtain the desired magnetic flux density. Conversely, if the azimuth angle is too large (i.e., if the circumferential dimension of the slit shape is long), resistance loss may increase and mechanical strength may decrease. For this reason, it is preferable to set the slit azimuth angle appropriately (for example, set it to a constant value) taking into consideration the shape of the coil portion 3, etc.

[0062] For example, Patent Documents 1 and 2 exemplify that the slit orientation angles of the first slit holes 31 and the second slit holes 32 are set within a range of [540 / s]° to [1440 / s]° (where s is the number of first slit holes 31 and the number of second slit holes 32), and the slit orientation angles of the first slit grooves 31b and the second slit grooves 32b are set within a range of [120 / s]° to [600 / s]° (where s is the number of first slit grooves 31b and the number of second slit grooves 32b), but are not limited to these.

[0063] Moreover, in the case of the first slit grooves 31b and the second slit grooves 32b in the figures, when viewed from the opening end faces 33 and 34, respectively, they extend in a shape that is biased clockwise as they move from the inside to the outside in the radial direction. Each of the first slit grooves 31b and each of the second slit grooves 32b having such a shape forms a spiral shape as a whole, as shown in Fig. 4, for example.

[0064] <Configuration example of contact part 4> The contact portion 4 has a plurality of third slit holes 41 (six in the figure) formed at predetermined intervals in the circumferential direction, each of which has a shape that penetrates the contact portion 4 in the thickness direction (axial direction) and a shape that extends radially outward from the axial side of the contact portion.

[0065] The third slit holes 41 have an arc shape that curves clockwise from the inside to the outside in the radial direction when viewed from the opposing side of the contact portion 4. The third slit holes 41 having such a shape form a spiral configuration as a whole, as shown in Fig. 5, for example.

[0066] A third slit open end 41a that opens radially outward is formed on the radially outer side of the third slit 41. A third slit closed end 41b, which is the opposite side of the third slit 41 from the third slit open end 41a, is located away from the axis 35 of the contact portion 4 radially outward.

[0067] In the case of the contact portion 4 in the figure, the third slit opening end 41a of each third slit hole 41 is provided so as to be positioned opposite the first slit opening end 31a (first slit groove 31b in the figure) of the first slit hole 31 in the axial direction. Also, the first slit opening end 31a of the electrode 2a and the first slit opening end 31a of the electrode 2b are positioned so as to be opposite each other in the axial direction.

[0068] As a result, each of the third slit holes 41 is configured to communicate with the first slit hole 31. When the electrodes 2a and 2b are close to each other (closed state), the first slit hole 31 and the third slit hole 41 of each of the electrodes 2a and 2b communicate with each other.

[0069] The third slit 41 shown above may also be formed in various ways so long as it is capable of generating a desired magnetic field.

[0070] For example, the third slit 41 may be formed while taking into consideration logical constraints on the contact portion 4. As a specific example, when the radius of the contact portion 4 is R0, the radius of curvature of the third slit 41 is Rs, the distance between the axis 35 of the contact portion 4 and the third slit closed end 41b is R1, and the distance between the axis 35 of the contact portion 4 and the center point P of curvature of the third slit 41 is R2, the following formulas (1) and (2) may be satisfied. Rs>R0-R2…(1) |R1-R2|≧Rs>(R1+R2)×0.7…(2).

[0071] By appropriately designing the contact portion 4 so as to satisfy the formulas (1) and (2), it is possible to form the third slit 41 so as to obtain the desired magnetic field generating function.

[0072] The position of the center of curvature P is not limited to the surface of the contact portion 4 as shown in FIG. 5, but may be located, for example, on the outer periphery of the contact portion 4 as long as it is within a range that satisfies the above formulas (1) and (2).

[0073] <Configuration example of adapter unit 5> The adapter part 5 has multiple fourth slit holes 51 (six in the figure) formed at predetermined intervals in the circumferential direction, each hole having a shape that penetrates the thickness direction (axial direction) of the adapter part 5 and a shape that extends radially outward from the axial side of the adapter part 5.

[0074] A fourth slit opening end 51a that opens radially outward is formed on the radially outer side of the fourth slit hole 51. In addition, a fourth slit closing end 51b, which is the opposite side of the fourth slit opening end 51a in the fourth slit hole 51, is positioned away from the axis 35 of the adapter part 5 radially outward.

[0075] In the case of the adapter part 5 in the figure, the fourth slit opening end 51a of each fourth slit hole 51 is provided so as to be positioned opposite the second slit opening end 32a (second slit groove 32b in the figure) of the second slit hole 32. As a result, each fourth slit hole 51 is configured to communicate with each second slit hole 32.

[0076] The fourth slit 51 shown above may also be formed in various ways so long as it is capable of generating a desired magnetic field.

[0077] In the case of each fourth slit hole 51 in the drawing, when the adapter part 5 is viewed from the opposite side of the facing direction, the fourth slit hole 51 has a shape (linear shape) that extends so as to be biased clockwise as it approaches the radially outer side from the inner side, forming a spiral shape as a whole, but is not limited to this. For example, the fourth slit hole 51 may be formed in an arc shape like the third slit hole 41.

[0078] Furthermore, in the case of the adapter part 5 in the figure, it is configured separately from the coil part 3, but this is not limited to this and it may be configured integrally with the coil part 3. In this case, the coil part 3 and the adapter part 5 form a cylindrical structure with a bottom as a whole.

[0079] <Configuration example of reinforcing portion 6> The reinforcing portion 6 has a surface-bonding portion 61 formed on the outer peripheral surface 60a of the peripheral wall 60, which is surface-bonded to the inner peripheral surface 30a of the coil portion 3. The surface-bonding portion 61 may be surface-bonded to the inner peripheral surface 30a with the reinforcing portion 6 provided on the inner peripheral side of the coil portion 3, and various configurations are possible. In the case of the reinforcing portion 6 shown in the figure, the annular surface-bonding portion 61, which expands radially outward, is formed at a location on the outer peripheral surface 60a of the peripheral wall 60 facing the surface-bonded portion 30b on the adapter portion 5 side, and the surface-bonding portion 61 is configured to be easily surface-bonded to the surface-bonded portion 30b, but is not limited to this.

[0080] For example, the surface-bonded portion 30b and the surface-bonded portion 61 in the figure are formed so as to face each other only in a partial axial area (the area on the adapter portion 5 side in the figure) on the inner surface 30a and the outer surface 60a, respectively, but they may be formed over the entire axial area, or may be formed only in the central area in the axial direction or the area on the contact portion 4 side.

[0081] <Other> The electrode 2 described above can be designed as appropriate to obtain desired electrode performance. For example, it can be designed to satisfy the above formulas (1) and (2). However, as an example of application to a general vacuum circuit breaker (VCB), it can also be set to satisfy the ranges shown below.

[0082] First, when the outer diameters of the coil portion 3 and the contact portion 4 (that is, equivalent to R0×2) are respectively set to φ, they are set to satisfy the following formula (3). 70mm≦φ≦150mm …(3).

[0083] Furthermore, if the axial dimension of the coil portion 3 is L and the radial thickness dimension of the peripheral wall 30 (corresponding to the radial dimension of the first slit groove 31b and the second slit groove 32b) is t, the dimensions can be set to satisfy the following equations (4) and (5). φ / 4mm≦L≦φmm …(4) 6mm≦t≦20mm …(5).

[0084] Furthermore, if the slit width (width in the short direction) of each of the first slit hole 31 and the second slit hole 32 is W1, the slit width dimension of the third slit hole 41 is W2, and the slit width dimension of the fourth slit hole 51 is W3, then the slit width dimensions can be set to satisfy the following equations (6), (7), and (8). 1mm≦W1≦3mm …(6) 1mm≦W2≦3mm …(7) 1mm≦W3≦5mm …(8).

[0085] Furthermore, if the number of third slit holes 41 is N1, the number of first slit holes 31 and second slit holes 32 is N2, and the number of first slit grooves 31b and second slit grooves 32b is N3, the numbers can be set to satisfy the following equations (9), (10), and (11). 3≦N1≦8 …(9) N1≦N2≦N1×2 …(10) N1 ≤ N3 ≤ N1 × 2 …(11).

[0086] If the radius of curvature of the third slit hole 41 is Rs and the distance between the electrodes 2a and 2b (the gap between the respective contact portions 4) is G, then the settings can be made to satisfy the following equations (12) and (13). φ / 4mm≦Rs≦φ / 2mm …(12) 15mm≦G≦100mm …(13).

[0087] <Verification example> Next, using a computer, models M1, M2, and M3 for analyzing the electrode 2 based on the embodiment were created, and various simulations were performed to conduct analysis. Models M1, M2, and M3 were set so that Rs / R0 was 37%, 42%, and 47%, respectively, and were created by appropriately setting the ratios to satisfy the above-mentioned formulas (1) to (13). Furthermore, as a comparative example for models M1 to M3, model M0 was created in which, instead of forming the arc-shaped third slit hole 41 in the contact portion 4, the third slit hole 40 was simply formed in a linear shape (a linear shape extending radially outward from the axial center side).

[0088] First, in models M2 and M0, the current density distribution and current vector when a current of 40 kArms is passed (i.e., when a current is passed between electrodes 2a and 2b) are analyzed by simulation, and an example of the analysis results is shown in Figure 6 based on the PU method.

[0089] 6, it can be seen that model M2 has more widely distributed high current density locations than model M0, and that the current density is higher, for example, at the radially outer locations (locations on the third slit opening end 41a side). Also, in model M2, there is a tendency for more current vectors to point in the circumferential direction (clockwise when viewed from the opposing side) than in model M0, and it can be seen that current flows more easily in the circumferential direction.

[0090] Next, in models M1 to M3, and M0, the longitudinal magnetic flux density |Bz| that can be generated (i.e., generated between electrodes 2a and 2b) when a current of 40 kArms is passed through was analyzed by simulation, and an example of the analysis results (an example in which the distance G in equation (13) above is set to 16 mm) is shown in Fig. 7 and Table 1 based on the PU method. Note that the horizontal axis in Fig. 7 indicates the radial position (distance) from the axis 35 of the contact portion 4.

[0091] [Table 1]

[0092] 7 and Table 1, model M1 has a similar maximum value of the longitudinal magnetic flux density |Bz| compared to model M0, but it can be seen that the magnetic flux density |Bz| at the outer radial location (the location on the third slit opening end 41a side) is larger. It can also be seen that the longitudinal magnetic flux density |Bz| increases as the radius of curvature Rs increases, as in models M2 and M3.

[0093] Next, the stress that can occur when the contacts are opened and closed was analyzed by simulation in models M2 and M0, and an example of the analysis results is shown in Table 2 based on the PU method.

[0094] [Table 2]

[0095] The results shown in Table 2 indicate that model M2 has lower stress that can occur when the contacts are opened and closed compared to model M0.

[0096] Therefore, compared to a conventional configuration such as model M0, the electrodes 2 created based on the examples, such as models M1 to M3, make it easier to form a long current path in the electrode 2 and make it easier for the current to flow in the circumferential direction in each electrode 2. This makes it easier to obtain a high magnetic flux density when breaking current in the electrode 2 and to uniformly distribute arcs that may occur in the electrode 2, making it easier to obtain the desired breaking performance.

[0097] Furthermore, even when the current-carrying cross-sectional area of ​​the coil portion 3 is increased to suppress resistance loss, it is relatively easy to obtain the desired magnetic flux density (easier than in conventional configurations), which contributes to both suppressing resistance loss in the coil portion 3, etc., and increasing magnetic flux density. Furthermore, stress that may occur when opening and closing the contacts can be suppressed, making it easier to maintain the desired electrode characteristics.

[0098] Although the present invention has been described in detail above only with respect to the specific examples, it will be apparent to those skilled in the art that various modifications are possible within the scope of the technical concept of the present invention, and it is natural that such modifications fall within the scope of the claims.

[0099] For example, the electrodes of the present invention are not limited to models M1 to M3 shown in the verification examples, and as a specific example, if they are created by setting them to satisfy the above equations (1) to (13), it is possible to obtain electrode characteristics that are better than those of model M0, similar to models M1 to M3. [Explanation of symbols]

[0100] 1A...Vacuum interrupter 2a...Fixed electrode, 12a...Fixed side current-carrying shaft 2b...Movable electrode, 12b...Movable side current-carrying shaft 3...coil portion, 31...first slit hole, 32...second slit hole, 31a...first opening end, 32a...second opening end, 31b...first slit groove, 32b...second slit groove, 35...axial center 4...contact portion, 41...third slit hole, 41a...third open end portion, 41b...third slit closed end portion 5...adapter part, 51...fourth slit hole 6...Reinforcement

Claims

1. A pair of electrodes are provided in a vacuum vessel having an insulating cylindrical body, the electrodes being opposed to each other in an axial direction of the cylindrical body and being capable of moving toward and away from each other; a pair of current-carrying shafts supporting the electrodes on opposite sides of the opposing direction; Equipped with Each of the electrodes is a cylindrical coil portion extending in the axial direction; a contact portion provided at an opening on the opposing side of 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; a reinforcing portion having a cylindrical shape with a smaller diameter than the coil portion and arranged concentrically on the inner periphery of the coil portion; and The coil portion a first slit hole having a shape penetrating the coil portion in a radial direction and extending in a Z-winding direction from a central portion of the coil portion in the axial direction toward the opposing direction, the first slit hole opening in the opposing direction and having a first slit opening end; a second slit hole having a shape penetrating in the radial direction and extending in a Z-winding direction from a central portion of the coil portion in the axial direction toward the opposite side of the opposing direction, the second slit hole opening on the opposite side of the opposing direction to form a second slit opening end portion; are alternately formed at predetermined intervals in the circumferential direction of the coil portion, The contact portion is a plurality of third slit holes, each having a shape penetrating in the axial direction and a shape extending from the axial side of the contact portion to the outside in the radial direction, each of which has a third slit opening end portion that opens to the outside in the radial direction, are formed at predetermined intervals in the circumferential direction; Each of the third slit holes is When viewed from the opposing side, the shape is an arc curved in a clockwise direction, a third slit closed end portion, which is opposite to the third slit open end portion of the third slit hole, is located away from the axis of the contact portion toward the outside in the radial direction, the third slit opening end is located opposite the first slit opening end, the third slit opening end of one of the electrodes and the third slit opening end of the other of the electrodes face each other in the axial direction, The adapter portion is a plurality of fourth slit holes, each having a shape penetrating in the axial direction and a shape extending from the axial side of the adapter portion to the outside in the radial direction, each of which has a fourth slit opening end portion that opens to the outside in the radial direction, are formed at predetermined intervals in the circumferential direction, The fourth slit opening end is located opposite the second slit opening end. An electrode structure characterized by:

2. The radius of the contact portion of each electrode is R ０ , the radius of curvature of the third slit hole is Rs, and the distance between the axis of the contact portion and the closed end of the third slit is R １ , the distance between the axis of the contact portion and the center of curvature of the third slit hole is R ２ 2. The electrode structure according to claim 1, wherein the following formulas (1) and (2) are satisfied: Rs>R ０ -R ２ …(1) |R １ -R ２ |≧Rs>(R １ +R ２ )×0.7 …(2)

3. 2. The electrode structure according to claim 1, wherein a first slit groove is formed in an opening edge surface of the first slit opening end portion, the first slit groove having a shape penetrating in the radial direction.

4. An electrode structure as described in claim 1, characterized in that the opening edge surface of the second slit opening end is formed with a second slit groove having a shape that penetrates in the radial direction.

5. A vacuum interrupter comprising the electrode structure according to any one of claims 1 to 4.

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