Vacuum valve and method for manufacturing vacuum valve
Patent Information
- Application Number
- JP2025541206
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Filing Date
- 2025-09-24
- Publication Date
- 2025-12-16
Abstract
Description
Vacuum valve and method for manufacturing the same
[0001] The present disclosure relates to a vacuum valve and a method for manufacturing the vacuum valve.
[0002] For example, a vacuum valve mounted as an arc extinguishing chamber in a vacuum circuit breaker or vacuum switchgear comprises an insulating container that maintains a vacuum state, a fixed electrode, a movable electrode, and a bellows. The insulating container has a fixed end plate and a movable end plate at both ends. The fixed electrode is fixed to the insulating container via the fixed end plate. The movable electrode is connected to the movable end plate via a bellows. One end of the bellows is connected to the movable end plate and the other end is connected to the movable electrode. The movable electrode is connected to an operating mechanism outside the insulating container. This allows the vacuum inside the insulating container to be opened and closed.
[0003] Vacuum valves are sometimes placed inside tanks and used in an atmosphere of pressurized dry air or insulating gas, such as sulfur hexafluoride gas. Because the insulating container is a vacuum, the bellows is subjected to a pressure difference between the vacuum and the insulating gas from outside the container. If this pressure difference is large, the bellows will buckle. Then, the opening and closing operation of the vacuum valve will cause the bellows to rupture prematurely, resulting in a vacuum leak. For this reason, bellows must be used in a low-pressure gas atmosphere. However, low-pressure insulating gas has poorer insulating performance than high-pressure insulating gas. This has led to the need to increase the size of the products, such as by increasing the insulation distance of each component of the vacuum circuit breaker and vacuum switchgear.
[0004] Therefore, for example, the vacuum valve in Patent Document 1 has another bellows on the back surface of the movable end plate. This configuration allows for three gas compartments: inside the vacuum valve, inside the bellows, and outside the vacuum valve. This distributes the pressure load and prevents the bellows from buckling, making it possible to use the bellows even in a high-pressure insulating gas atmosphere.
[0005] Japanese Unexamined Patent Publication No. 61-121221
[0006] However, in the invention described in Patent Document 1, a bellows is also provided on the back surface of the movable end plate, which increases the overall length of the vacuum interrupter. As the overall length of the vacuum interrupter increases, the overall size of the vacuum circuit breaker and vacuum switch increases. Furthermore, as the size of the movable electrode increases, the mass also increases, which increases the inertial force generated when the vacuum interrupter starts or finishes opening and closing operations. This requires an increase in the mechanical strength of the operating mechanism, etc.
[0007] The present disclosure has been made to solve the above-mentioned problems, and aims to provide a vacuum valve and a method for manufacturing a vacuum valve that can suppress buckling displacement of a bellows without extending the overall length of the vacuum valve or the movable side electrode.
[0008] The vacuum valve according to the present disclosure is characterized by comprising an insulating container that maintains a vacuum inside and has a fixed end plate and a movable end plate at each end, a fixed electrode rod fixed to the fixed end plate and having a fixed contact joined to its end, a movable electrode rod that is arranged on the movable end plate and has a movable contact joined to its end that is arranged so that it can be moved toward and away from the fixed contact, and a bellows that has one end joined to the movable end plate and the other end joined to the movable electrode rod, and has a bellows structure that is expandable and contractible in the driving direction of the movable electrode rod, with the valley portion of the bellows structure coming into contact with the movable electrode rod.
[0009] The vacuum valve according to the present disclosure is characterized by comprising: an insulating container that maintains a vacuum inside and has a fixed end plate and a movable end plate at each end; a fixed electrode rod fixed to the fixed end plate and having a fixed contact joined to its end; a movable electrode rod that is arranged on the movable end plate and has a movable contact joined to its end, the movable contact being arranged so that it can be moved toward and away from the fixed contact; a bellows that has one end joined to the movable end plate and the other end joined to the movable electrode rod and has a bellows structure that is expandable and contractible in the driving direction of the movable electrode rod; a first guide that is joined to the other end of the bellows, has an outer periphery that contacts the valleys of the bellows structure and an inner periphery that contacts the movable electrode rod, and has a protrusion; and a second guide that is joined to the movable end plate, has an outer periphery that contacts the valleys of the bellows structure, an inner periphery that contacts the movable electrode rod, and has a protrusion that can be fitted into the first guide.
[0010] The vacuum valve according to the present disclosure is characterized by comprising an insulating container that maintains a vacuum inside and has a fixed end plate and a movable end plate at each end, a fixed electrode rod fixed to the fixed end plate and having a fixed contact joined to its end, a movable electrode rod that is arranged on the movable end plate and has a movable contact joined to its end that is arranged so that it can be moved toward and away from the fixed contact, a bellows with one end joined to the movable end plate and the other end joined to the movable electrode rod and having a bellows structure that can expand and contract in the driving direction of the movable electrode rod, and a thin ring or ring segment with a U-shaped cross section inserted into the valley of the bellows structure.
[0011] In addition, the manufacturing method of the vacuum valve according to the present disclosure is characterized by comprising the steps of fitting together a plurality of cylindrical bodies of different diameters to form a multilayer cylindrical body, forming the side walls of the multilayer cylindrical body into a bellows shape to form a multilayer bellows having a bellows structure, sealing the spaces between the layers at both ends of the multilayer bellows, and positioning the multilayer bellows so that the valleys of the bellows structure of the multilayer bellows come into contact with the movable electrode rod.
[0012] According to the present disclosure, in a vacuum valve, a valley portion of the bellows accordion structure contacts a movable electrode rod or a guide, or a thin plate ring or ring segments with a U-shaped cross section are joined to the valley portion of the bellows accordion structure, thereby providing a vacuum valve and a method for manufacturing the vacuum valve that can suppress buckling displacement of the bellows.
[0013] 1 is a schematic cross-sectional view of a vacuum interrupter of embodiment 1. FIG. 2 is a flowchart showing the manufacturing process of a bellows of embodiment 1. FIG. 3 is a schematic cross-sectional view showing the manufacturing process of a multilayer cylindrical body of embodiment 1. FIG. 4 is a schematic cross-sectional view showing the manufacturing process of a bellows shape of a bellows of embodiment 1. FIG. 5 is a schematic cross-sectional view showing the process of sealing between layers at both ends of the multilayer bellows of embodiment 1. FIG. 6 is a flowchart showing the assembly process of a vacuum interrupter of embodiment 1. FIG. 7 is a schematic cross-sectional view of a vacuum interrupter of embodiment 2. FIG. 8 is a perspective view of a first guide of embodiment 2. FIG. 9 is a perspective view of a second guide of embodiment 2. FIG. 10 is a perspective view of a first guide and a second guide of embodiment 2. FIG. 11 is a flowchart showing the assembly process of a vacuum interrupter of embodiment 2. FIG. 12 is a schematic cross-sectional view of a vacuum interrupter of embodiment 3. FIG. 13 is a schematic cross-sectional view of a bellows of embodiment 3. FIG. 14 is a perspective view of a ring segment of embodiment 3. FIG. 15 is a flowchart showing the assembly process of a vacuum interrupter of embodiment 3.
[0014] A vacuum valve 100 and a method for manufacturing the vacuum valve 100 according to an embodiment will be described below with reference to the drawings. The following embodiments are merely examples, and the embodiments can be combined and modified as appropriate. In the drawings, similar components are designated by the same reference numerals.
[0015] The coordinate axes of an XYZ Cartesian coordinate system are shown in the diagram. In the cross-sectional schematic diagram of the vacuum interrupter 100 shown in Figure 1, the direction in which the movable electrode 3 is driven is the Z-axis direction, the direction in which the movable electrode 3 approaches the fixed electrode 2 is the +Z-axis direction, and the direction in which it moves away from the fixed electrode 2 is the -Z-axis direction. The direction from the fixed electrode 2 toward the shield 4 is the Y-axis direction, the direction from the fixed electrode 2 toward the shield 4a is the +Y-axis direction, and the direction from the fixed electrode 2 toward the shield 4b is the -Y-axis direction. Furthermore, in the cross-sectional schematic diagram of the vacuum interrupter 100 shown in Figure 1, the direction from the back to the front is the +X-axis direction, and the direction from the front to the back is the -X-axis direction.
[0016] Embodiment 1 A vacuum interrupter 100 in embodiment 1 will be described with reference to Fig. 1. Fig. 1 is a schematic cross-sectional view of the vacuum interrupter 100 in embodiment 1. The vacuum interrupter 100 comprises an insulating container 1, a fixed electrode 2, a movable electrode 3, a bellows 5, and a shield 4.
[0017] The insulating container 1 comprises a cylindrical container 1a made of ceramic or the like, and a fixed end plate 1b and a movable end plate 1c provided at both ends of the cylindrical container 1a. The fixed end plate 1b and the movable end plate 1c are brazed to the cylindrical container 1a, and the interior of the insulating container 1 is maintained under vacuum. The insulating container 1 has a fixed electrode 2 and a movable electrode 3 at both ends, and a shield 4 and a bellows 5 inside. The shield 4 is disposed to surround the fixed electrode 2 and the movable electrode 3 and protects the inner surface of the insulating container 1. The fixed electrode 2 has a fixed contact 2a and a fixed electrode rod 2b. The fixed contact 2a is joined to the end of the fixed electrode rod 2b. The fixed electrode rod 2b is fixed to the insulating container 1 via the fixed end plate 1b. The movable electrode 3 has a movable contact 3a and a movable electrode rod 3b. The movable contact 3a is joined to the end of the movable electrode rod 3b and is arranged so as to be able to move toward and away from the fixed contact 2a. One end of the bellows 5 is joined to the movable end plate 1c and the other end is joined to the movable electrode rod 3b. The movable electrode 3 is joined to an operating mechanism (not shown) outside the insulating container 1. This allows the vacuum valve 100 to be opened and closed while maintaining the degree of vacuum inside the insulating container 1.
[0018] The bellows 5 has a bellows structure that is expandable and contractible in the Z-axis direction, which is the driving direction of the movable electrode 3b. The bellows 5 preferably has a multi-layer structure. In this case, the innermost layer 5a of the bellows 5 is the layer closest to the movable electrode 3b in the multi-layer structure. The bellows 5 also has a valley 5b of the bellows structure and a body portion 5c, which is the portion other than the valley. The bellows 5 is positioned so that the valley 5b of the bellows structure in the innermost layer 5a contacts the movable electrode 3b. Here, the entire circumference of the valley 5b of the bellows structure does not need to contact the movable electrode 3b. In other words, only a portion of the valley 5b of the bellows structure may contact the movable electrode 3b. This prevents the bellows 5 from buckling in the XY plane. Furthermore, by arranging the bellows 5 so that the valleys 5b of the bellows structure in the innermost layer 5a come into contact with the movable electrode rod 3b, the valleys 5b of the bellows structure slide against the movable electrode rod 3b, generating friction when the vacuum valve 100 is opened or closed. This reduces transient vibrations of the bellows 5 and improves the fatigue strength of the bellows 5.
[0019] As described above, the bellows 5 preferably has a multilayer structure. In this case, the multilayer structure of the bellows 5 may be configured such that the layers are sealed at both ends and are not sealed anywhere other than at both ends of the multilayer structure. This configuration prevents vacuum leakage unless a tear occurs in any of the layers of the multilayer structure. This improves the opening and closing life of the vacuum valve 100. Furthermore, the multilayer structure of the bellows 5 is not sealed anywhere other than at both ends, resulting in a structure in which slippage occurs between the layers. This reduces transient vibrations of the bellows 5 and improves the fatigue strength of the bellows 5.
[0020] Furthermore, at least one of the valleys 5b of the bellows structure of the innermost layer 5a of the bellows 5 and the outer periphery 3c of the movable electrode rod 3b may be coated with an insulating material. For example, a resin part or the like may be sandwiched between the movable end plate 1c and the current-carrying part. This prevents the interruption current from flowing through the bellows 5 when the vacuum valve 100 is opened to interrupt the current.
[0021] 1, the movable electrode bar 3b is cylindrical, but may be a square column. Even in this case, the bellows 5 is arranged so that the valleys 5b of the bellows structure in the innermost layer 5a come into contact with the movable electrode bar 3b.
[0022] Next, a method for manufacturing the vacuum valve 100 according to the first embodiment will be described. The method will be divided into a manufacturing process for the bellows 5 and an assembly process for the vacuum valve 100.
[0023] The manufacturing process of the bellows 5 will be described with reference to FIGS. 2, 3, 4, and 5. FIG. 2 is a flowchart showing the manufacturing process of the bellows according to the first embodiment. FIG. 3 is a schematic diagram showing the manufacturing process of the multilayer tubular body according to the first embodiment. FIG. 4 is a schematic cross-sectional view showing the manufacturing process of the bellows according to the first embodiment. FIG. 5 is a schematic cross-sectional view showing the process of sealing the layers at both ends of the multilayer bellows according to the first embodiment. In step S101, a plurality of tubular bodies with different diameters are fitted together to manufacture the multilayer tubular body 6. Note that while FIG. 3 shows the manufacturing process of a two-layer tubular body, a tubular body with three or more layers may also be manufactured. In step S102, the multilayer tubular body 6 is inserted into a cavity of a mold 7, and the side wall of the multilayer tubular body 6 is hydraulically molded into a bellows shape. The mold 7 has a cavity capable of accommodating the tubular body. The cavity also has a corrugated inner wall. This allows the manufacturing of the multilayer bellows 5 having a bellows structure. In step S103, the layers of the multi-layered bellows 5 are not sealed apart from the ends 8, but are sealed apart by brazing at the ends 8. This completes the manufacturing process for the bellows 5 according to the first embodiment.
[0024] The assembly process of the vacuum interrupter 100 will be described using FIG. 6 . FIG. 6 is a flowchart showing the assembly process of the vacuum interrupter of the first embodiment. In step S111, the shield 4 is attached to the inside of a cylindrical container 1a made of ceramics or the like. In step S112, the fixed contact 2a, the fixed electrode 2b, and the fixed end plate 1b are brazed together. In step S113, the movable contact 3a, the movable electrode 3b, the bellows 5, and the movable end plate 1c are brazed together. In step S113, the bellows 5 is positioned so that the trough 5b of the bellows structure in the innermost layer 5a contacts the movable electrode 3b. The order of steps S111 to S113 is not limited to the above, and may be reversed or performed simultaneously. In step S114, the fixed end plate 1b and the movable end plate 1c are brazed to both ends of the cylindrical container 1a, respectively. Here, the movable contact 3a is arranged so that it can be brought into contact with and separated from the fixed contact 2a. This completes the assembly process for the vacuum interrupter 100 according to the first embodiment.
[0025] As described above, in the vacuum interrupter 100 of the first embodiment, the valley portion 5b of the bellows structure in the innermost layer 5a of the bellows 5 is arranged so as to contact the movable electrode rod 3b. This configuration suppresses buckling displacement of the bellows 5 in the XY plane. This allows the bellows 5 to be used even in high-voltage insulating gas, enabling the size of the vacuum interrupter 100 to be reduced. Furthermore, this configuration allows the valley portion 5b of the bellows structure and the movable electrode rod 3b to slide against each other when the vacuum interrupter 100 is opened or closed, generating friction. This reduces transient vibration of the bellows 5 and improves the fatigue strength of the bellows 5. Furthermore, improving the fatigue strength of the bellows 5 allows the size of the vacuum interrupter 100 to be reduced. This also allows the size of the vacuum circuit breaker and vacuum switchgear to be reduced.
[0026] The multilayer structure of the bellows 5 may also be configured such that the interlayer spaces between the layers are sealed at both ends, but not at other ends. This configuration prevents vacuum leakage unless a tear occurs in any of the layers of the multilayer structure. For example, even if the valleys 5b of the bellows structure in the innermost layer 5a are worn away by friction with the movable electrode rod 3b, causing a tear in the valleys 5b of the bellows structure in the innermost layer 5a, the interlayer spaces between the layers are sealed at both ends of the bellows 5, preventing vacuum leakage through gaps between the layers. This improves the opening and closing life of the vacuum valve 100. Furthermore, the multilayer structure of the bellows 5 is not sealed at other than the ends, allowing for slippage between the layers. This reduces transient vibrations in the bellows 5 and improves the fatigue strength of the bellows 5.
[0027] Furthermore, at least one of the valleys 5b of the bellows structure of the innermost layer 5a and the outer periphery 3c of the movable electrode rod 3b may be coated with an insulating material. With this configuration, when the vacuum valve 100 is opened to interrupt current, it is possible to prevent the interrupting current from flowing through the bellows 5. As a result, it is possible to prevent cracks from occurring in the bellows 5 due to welding and peeling of the bellows 5 ...
[0028] 1 may be a rectangular pillar. In this case, the bellows 5 is arranged so that the valleys 5b of the bellows structure in the innermost layer 5a come into contact with the movable electrode 3b. This provides the same effect of suppressing buckling displacement of the bellows 5 in the XY plane.
[0029] The manufacturing method for the vacuum valve 100 in the first embodiment includes the steps of fitting together multiple cylindrical bodies of different diameters to form a multilayer cylindrical body 6, forming the side walls of the multilayer cylindrical body into a bellows shape to form a multilayer bellows 5 having a bellows structure, sealing the spaces between the layers at both ends 8 of the multilayer bellows 5, and positioning the bellows 5 so that the valleys 5b of the bellows structure of the multilayer bellows 5 contact the movable electrode rod 3b. This allows the manufacturing of a vacuum valve 100 that can prevent buckling displacement of the bellows 5 because the valleys 5b of the bellows structure of the bellows 5 contact the movable electrode rod 3b. Furthermore, the above manufacturing method allows the manufacturing of a multilayer bellows 5 in which the spaces between the layers at both ends 8 are sealed. This prevents vacuum leakage unless tears occur in any of the layers of the multilayer structure of the bellows 5.
[0030] Although the bellows 5 in the first embodiment has been described as having a multi-layer structure, it may have a single-layer structure. Even in this case, the bellows 5 is arranged so that the valleys 5b of the bellows structure come into contact with the movable electrode bar 3b. This provides the same effect of suppressing buckling displacement of the bellows 5 in the XY plane.
[0031] Embodiment 2. A vacuum interrupter 101 according to embodiment 2 will be described with reference to FIG. 7 . FIG. 7 is a schematic cross-sectional view of the vacuum interrupter 101 according to embodiment 2. The vacuum interrupter 100 according to embodiment 1 is characterized in that the valleys 5b of the bellows structure in the innermost layer 5a of the bellows 5 are arranged so as to contact the movable electrode rod 3b. The vacuum interrupter 101 according to embodiment 2 differs from the vacuum interrupter 100 according to embodiment 1 in that it includes a first guide 9 and a second guide 10, and is characterized in that the valleys 5b of the bellows structure in the innermost layer 5a of the bellows 5 are arranged so as to contact at least one of the outer periphery 9a of the first guide 9 and the outer periphery 10a of the second guide 10. The same components as those according to embodiment 1 are designated by the same reference numerals.
[0032] The first guide 9 is joined to the other end of the bellows 5. An outer circumferential portion 9a of the first guide 9 is disposed so as to contact a valley portion 5b of the bellows structure in the innermost layer 5a of the bellows 5. An inner circumferential portion 9b of the first guide 9 is disposed so as to contact the movable electrode rod 3b.
[0033] The second guide 10 is joined to the movable-side end plate 1c. The outer periphery 10a of the second guide 10 is arranged so as to contact the valley portion 5b of the bellows structure in the innermost layer 5a of the bellows 5. The inner periphery 10b of the second guide 10 is arranged so as to contact the movable-side electrode rod 3b.
[0034] Fig. 8 is a perspective view of a first guide 9 according to the second embodiment, Fig. 9 is a perspective view of a second guide 10 according to the second embodiment, and Fig. 10 is a perspective view of the first guide 9 and the second guide 10 according to the second embodiment. As shown in Figs. 8 and 9, the first guide 9 and the second guide 10 have projections that can fit together. As shown in Fig. 10, the first guide 9 and the second guide 10 are arranged so that the projections can fit together.
[0035] Furthermore, the first guide 9 and the second guide 10 are arranged so that at least one of the outer periphery 9 a of the first guide 9 and the outer periphery 10 a of the second guide 10 comes into contact with the valleys 5 b of the bellows structure in the innermost layer 5 a of the bellows 5. This prevents the bellows 5 from buckling and displacing in the XY plane.
[0036] Furthermore, the entire circumference of the valley portion 5b of the bellows structure does not have to be in contact with the first guide 9 and the second guide 10. In other words, it is sufficient that a portion of the valley portion 5b of the bellows structure is in contact with at least one of the first guide 9 and the second guide 10.
[0037] Furthermore, it is desirable that the first guide 9 and the second guide 10 be made of an insulating material such as a resin material and be structured so that no current flows through the bellows 5. For example, the vacuum valve 101 has a structure in which a resin part or the like is sandwiched between the movable end plate 1c and a current-carrying part. With the above configuration, the vacuum valve 101 has a structure in which the outer periphery 9a of the first guide 9, the outer periphery 10a of the second guide 10, and the movable end plate 1c, which come into contact with the bellows 5, are insulated from one another. This prevents a breaking current from flowing through the bellows 5 when the vacuum valve 101 opens to break current.
[0038] Next, a description will be given of a method for manufacturing the vacuum interrupter 101 in the second embodiment. The manufacturing process of the bellows 5 is the same as the manufacturing process of the bellows 5 in the first embodiment.
[0039] The assembly process of the vacuum interrupter 101 will be described using FIG. 11 . FIG. 11 is a flowchart showing the assembly process of the vacuum interrupter of the second embodiment. In step S211, a shield 4 is attached to the interior of a cylindrical container 1a made of ceramics or the like. In step S212, the fixed contact 2a, the fixed electrode 2b, and the fixed end plate 1b are brazed together. In step S213, the movable contact 3a, the movable electrode 3b, the bellows 5, and the movable end plate 1c are brazed together. In step S213, the bellows 5 is positioned so that the trough 5b of the bellows structure in the innermost layer 5a contacts the movable electrode 3b. The order of steps S211 to S213 is not limited to the above-described order; they may be reversed or performed simultaneously. In step S214, the fixed end plate 1b and the movable end plate 1c are brazed to both ends of the cylindrical container 1a, respectively. Here, the movable contact 3a is arranged so that it can move toward and away from the fixed contact 2a. In step S215, the first guide 9 is attached to the other end of the bellows 5, and the second guide 10 is attached to the movable end plate 1c. In step S215, the first guide 9 and the second guide 10 are arranged so that at least one of the outer periphery 9a of the first guide 9 and the outer periphery 10a of the guide 10 contacts the valley portion 5b of the bellows structure in the innermost layer 5a of the bellows 5. This completes the assembly process for the vacuum interrupter 101 in embodiment 2.
[0040] As described above, the vacuum interrupter 101 in the second embodiment has a first guide 9 and a second guide 10. The first guide 9 is joined to the other end of the bellows 5, and the outer circumferential portion 9a of the first guide 9 contacts the valley portion 5b of the bellows structure of the bellows 5, the inner circumferential portion 9b contacts the movable-side electrode rod 3b, and has a protrusion. The second guide 10 is joined to the movable-side end plate 1c, and the outer circumferential portion 10a of the second guide 10 contacts the valley portion 5b of the bellows structure of the bellows 5, the inner circumferential portion 10b of the second guide 10 contacts the movable-side electrode rod 3b, and has a protrusion that can be fitted into the first guide 9. This prevents the bellows 5 from buckling in the XY plane.
[0041] Furthermore, by arranging at least one of the outer periphery 9a of the first guide 9 and the outer periphery 10a of the second guide 10 so that they come into contact with the valleys 5b of the bellows structure in the innermost layer 5a of the bellows 5, the first guide 9 or the second guide 10 comes into contact with the valleys 5b of the bellows structure when the vacuum valve 101 is opened or closed, thereby reducing transient vibrations of the bellows 5. This improves the opening and closing life of the vacuum valve 101 compared to a configuration in which the vacuum valve 101 is configured with only either the first guide 9 or the second guide 10.
[0042] Furthermore, the first guide 9 and the second guide 10 may be made of an insulating material such as a resin material. With the above configuration, it is possible to prevent a breaking current from flowing through the bellows 5 when the vacuum valve 101 is opened to break the current. As a result, it is possible to prevent cracks from occurring in the abdomen 5c of the bellows 5 due to welding and peeling of the abdomens 5c of the bellows 5.
[0043] Furthermore, the first guide 9 and the second guide 10 may be made of a material that reduces wear when sliding against the bellows 5 compared to when the first guide 9 and the second guide 10 are made of metal. This configuration reduces wear on the bellows 5 due to sliding friction and suppresses the occurrence of cracks in the valleys 5b of the bellows structure. This makes it easier to use a single-layer bellows 5. This reduces the size of the bellows 5, allowing the size of the vacuum valve 101 to be reduced.
[0044] Furthermore, a manufacturing method of the vacuum valve 101 in the second embodiment includes the steps of fitting together a plurality of cylindrical bodies of different diameters to form a multilayer cylindrical body 6, forming the side walls of the multilayer cylindrical body into a bellows shape to form a multilayer bellows 5 having a bellows structure, sealing the spaces between the layers at both ends 8 of the multilayer bellows 5, and arranging the first guide 9 and / or the second guide 10 so that at least one of the outer periphery 9 a of the first guide 9 and the outer periphery 10 a of the second guide 10 contacts the valleys 5 b of the bellows structure in the innermost layer 5 a of the bellows 5. This allows the vacuum valve 101 to be manufactured, which can suppress buckling displacement of the bellows 5 because the valleys 5 b of the bellows structure of the bellows 5 contact at least one of the outer periphery 9 a of the first guide 9 and the outer periphery 10 a of the second guide 10. Furthermore, the above manufacturing method allows the manufacturing of a multilayer bellows 5 in which the spaces between the layers at both ends 8 are sealed. This makes it possible to prevent vacuum leakage unless a tear occurs in any of the layers of the multi-layer structure of the bellows 5.
[0045] Although the bellows 5 in the second embodiment has been described as having a multi-layer structure, it may also have a single-layer structure. Even in this case, the bellows 5 is arranged so that at least one of the outer periphery 9 a of the first guide 9 and the outer periphery 10 a of the second guide 10 contacts the valleys 5 b of the bellows structure of the bellows 5. This provides the same effect of suppressing buckling displacement of the bellows 5 in the XY plane.
[0046] Although the movable electrode bar 3b in FIG. 7 is cylindrical, it may be a rectangular prism. In this case, the cross sections of the inner circumferential portion 9b of the first guide 9 and the inner circumferential portion 10b of the second guide 10 have the same polygonal shape as the cross section of the rectangular prism. With the above configuration, rotation of the movable electrode bar 3b about the Z axis can be suppressed. This also suppresses rotation of the bellows 5, the other end of which is joined to the movable electrode bar 3b, about the Z axis, and suppresses buckling displacement of the bellows 5 in the XY plane.
[0047] Furthermore, the cross sections of the outer periphery 9 a of the first guide 9 and the outer periphery 10 a of the second guide 10 may be polygonal. Even in this case, the first guide 9 and the second guide 10 are arranged so that at least one of the outer periphery 9 a of the first guide 9 and the outer periphery 10 a of the second guide 10 contacts the valleys 5 b of the bellows structure in the innermost layer 5 a of the bellows 5. This provides the same effect of suppressing buckling displacement of the bellows 5 in the XY plane.
[0048] Embodiment 3. A vacuum interrupter 102 according to embodiment 3 will be described with reference to FIG. 12 . FIG. 12 is a schematic cross-sectional view of the vacuum interrupter 102 according to embodiment 3. The vacuum interrupter 100 according to embodiment 1 is characterized in that the valley portion 5b of the bellows structure in the innermost layer 5a of the bellows 5 is positioned so as to contact the movable electrode rod 3b. The vacuum interrupter 102 according to embodiment 3 includes a thin, U-shaped ring 11. Here, the ring 11 is not limited to an annular shape and may have a segmented ring shape as shown in FIG. 14 . Hereinafter, the term "ring 11" will be used to collectively refer to an annular ring and segments of an annular ring. The vacuum interrupter 102 according to embodiment 3 differs from the vacuum interrupter 100 according to embodiment 1 in that the ring 11 is inserted into the valley portion 5b of the bellows structure in the outermost layer 5d of the bellows 5. Components similar to those according to embodiment 1 are designated by the same reference numerals.
[0049] FIG. 13 is a schematic cross-sectional view of the bellows 5 according to the third embodiment. FIG. 14 is a perspective view of a segment of the ring 11 according to the third embodiment. As shown in FIG. 14, the ring 11 is a thin plate having a U-shaped cross section. The ring 11 is inserted into the valley portion 5b of the bellows structure in the outermost layer 5d of the bellows 5. This reinforces the bellows 5 with the ring 11, increasing the rigidity of the bellows 5 and suppressing buckling displacement of the bellows 5 in the XY plane.
[0050] In addition, the ring 11 has a structure in which the abdominal portion 11a, which corresponds to the side portion of the U-shape of the ring 11, is joined to the outermost layer 5d, and the R portion 11b, which corresponds to the valley portion of the U-shape of the ring 11, is not joined to the outermost layer 5d.
[0051] Next, a description will be given of a method for manufacturing the vacuum interrupter 102 in the third embodiment. The manufacturing process of the bellows 5 is the same as the manufacturing process of the bellows 5 in the first embodiment.
[0052] The assembly process of the vacuum interrupter 102 will be described using FIG. 15 . FIG. 15 is a flowchart showing the assembly process of the vacuum interrupter of the third embodiment. In step S311, a shield 4 is attached to the interior of a cylindrical container 1a made of ceramics or the like. In step S312, the fixed contact 2a, the fixed electrode 2b, and the fixed end plate 1b are brazed together. In step S313, a ring 11 is inserted into the trough 5b of the bellows structure in the outermost layer 5d of the bellows 5, and the movable contact 3a, the movable electrode 3b, the bellows 5, the ring 11, and the movable end plate 1c are brazed together. Steps S311 to S313 are not limited to the order described above; they may be reversed or performed simultaneously. In step S314, the fixed end plate 1b and the movable end plate 1c are brazed to both ends of the cylindrical container 1a. Here, the movable contact 3a is positioned so that it can be moved toward or away from the fixed contact 2a. This completes the assembly process of the vacuum interrupter 102 in the third embodiment.
[0053] As described above, the vacuum valve 102 in this embodiment has the ring 11 inserted into the valley portion 5b of the bellows structure in the outermost layer 5d of the bellows 5. This reinforces the bellows 5 with the ring 11, increasing the rigidity of the bellows 5 and suppressing buckling displacement of the bellows 5 in the XY plane. Furthermore, the above-described configuration can reduce transient vibrations of the bellows 5 and improve the fatigue strength of the bellows 5.
[0054] Furthermore, the ring 11 has a structure in which the belly portion 11a of the ring 11 is joined to the outermost layer 5d, but the curved portion 11b of the ring 11 is not joined to the outermost layer 5d. This structure suppresses an increase in the thickness of the bellows 5 compared to when the ring 11 is joined to the outermost layer 5d at the curved portion 11b of the ring 11. As a result, an increase in bending stress in the valley portion 5b of the bellows structure of the bellows 5 during the opening and closing operations of the vacuum valve 102 can be suppressed. This improves the fatigue life of the bellows 5. Furthermore, by joining the belly portion 11a of the ring 11 to the outermost layer 5d, an airtight seal is established between the ring 11 and the outermost layer 5d. This structure prevents vacuum leakage even if a tear occurs in the valley portion 5b of the bellows structure of the outermost layer 5d of the bellows 5.
[0055] Furthermore, the rounded portion 11b of the ring 11 and the outermost layer 5d may not be in contact with each other. Even in this case, the ring 11 reinforces the bellows 5, increasing the rigidity of the bellows 5, and thus the same effect of suppressing buckling displacement of the bellows 5 in the XY plane direction can be achieved.
[0056] Furthermore, when the rounded portion 11b of the ring 11 and the outermost layer 5d are in contact with each other, slippage occurs between the rounded portion 11b of the ring 11 and the outermost layer 5d. When the rounded portion 11b of the ring 11 and the outermost layer 5d are not in contact with each other, the rounded portion 11b of the ring 11 and the outermost layer 5d do not interfere with each other. Therefore, regardless of whether the rounded portion 11b of the ring 11 and the outermost layer 5d are in contact with each other, an increase in bending stress in the valley portions 5b of the bellows structure of the bellows 5 can be suppressed.
[0057] The manufacturing method for the vacuum valve 102 in this embodiment includes the steps of fitting together multiple cylindrical bodies of different diameters to form a multilayer cylindrical body 6, forming the side walls of the multilayer cylindrical body into a bellows shape to form a multilayer bellows 5 having a bellows structure, sealing the spaces between the layers at both ends 8 of the multilayer bellows 5, and inserting the rings 11 or segments of the rings 11 into the valleys 5b of the bellows structure in the outermost layer 5d of the bellows 5. This reinforces the bellows 5 with the rings 11, thereby enabling the manufacture of a vacuum valve 102 that can prevent buckling displacement of the bellows 5. Furthermore, the above manufacturing method allows the manufacture of a multilayer bellows 5 in which the spaces between the layers at both ends 8 are sealed. This prevents vacuum leakage unless tears occur in any of the layers of the multilayer structure of the bellows 5.
[0058] Although the bellows 5 in the third embodiment has been described as having a multi-layer structure, it may also have a single-layer structure. Even in this case, the ring 11 is inserted into the valley portion 5b of the bellows structure. This provides the same effect of suppressing buckling displacement of the bellows 5 in the XY plane.
[0059] 12 is described as ring 11 divided into two, the number of divisions is not limited to one. That is, ring 11 divided into two or more divisions may be inserted into valleys 5b of the bellows structure in outermost layer 5d. In this case, the same effect of suppressing buckling displacement of bellows 5 in the XY plane direction is achieved.
[0060] Furthermore, the rings 11 do not need to be inserted into all of the valley portions 5b of the bellows structure in the outermost layer 5d of the bellows 5. For example, the rings 11 may be inserted into the valley portions 5b of the bellows structure at both ends of the bellows 5 that have a large expansion / contraction range in the Z-axis direction, which is the driving direction of the movable electrode bar 3b, or in the center of the bellows 5, where buckling is likely to occur. In this case, it is not necessary to insert the rings 11 or segments of the ring 11 into any portions other than the both ends and the center of the bellows 5. Even in this case, the same effect of suppressing buckling displacement of the bellows 5 in the XY plane direction is achieved.
[0061] Furthermore, all rings 11 do not need to have the same thickness. For example, thicker rings 11 may be inserted in the valleys 5b of the bellows structure at both ends of the bellows 5, which have a large expansion / contraction range in the Z-axis direction, which is the driving direction of the movable electrode rod 3b, or in the center of the bellows 5, where buckling is likely to occur. In this case, rings 11 thinner than the rings 11 inserted at both ends and the center of the bellows 5 may be inserted in places other than both ends and the center of the bellows 5. This can more effectively prevent buckling displacement of the bellows 5 in the XY plane compared to when thinner rings 11 are inserted at both ends and the center of the bellows 5. Furthermore, with the above configuration, transient vibration of the bellows 5 can be more effectively reduced and the fatigue strength of the bellows 5 can be improved compared to when thinner rings 11 are inserted at both ends and the center of the bellows 5.
[0062] 1 Insulating container, 1a Cylindrical container, 1b Fixed side end plate, 1c Movable side end plate, 2 Fixed side electrode, 2a Fixed side contact, 2b Fixed side electrode rod, 3 Movable side electrode, 3a Movable side contact, 3b Movable side electrode rod, 3c Outer periphery of movable side electrode rod, 4 Shield, 5 Bellows, 5a Innermost diameter layer of bellows, 5b Valley portion of bellows structure in innermost diameter layer of bellows, 5c Bellows middle portion, 5d Outermost diameter layer of bellows, 6 Multilayer cylindrical body, 7 Mold, 8 Both ends of multilayer bellows, 9 First guide, 9a Outer periphery of first guide, 9b Inner periphery of first guide, 10 Second guide, 10a Outer periphery of second guide, 10b Inner periphery of second guide, 11 Ring, 11a Middle portion of ring, 11b R portion of ring
Claims
1. an insulating container whose interior is kept under vacuum and which has a fixed end plate and a movable end plate at both ends; a fixed electrode rod fixed to the fixed end plate and having a fixed contact joined to an end thereof; a movable electrode rod disposed on the movable end plate and having a movable contact joined to an end thereof, the movable contact being arranged so as to be able to come into contact with and separate from the fixed contact; a bellows having one end joined to the movable-side end plate and the other end joined to the movable-side electrode bar, the bellows having a bellows structure that is expandable and contractible in the driving direction of the movable-side electrode bar, and a valley portion of the bellows structure that comes into contact with the movable-side electrode bar; A vacuum valve comprising:
2. an insulating container whose interior is kept under vacuum and which has a fixed end plate and a movable end plate at both ends; a fixed electrode rod fixed to the fixed end plate and having a fixed contact joined to an end thereof; a movable electrode rod disposed on the movable end plate and having a movable contact joined to an end thereof, the movable contact being arranged so as to be able to come into contact with and separate from the fixed contact; a bellows having a bellows structure, one end of which is joined to the movable-side end plate and the other end of which is joined to the movable-side electrode bar, and which is expandable and contractible in the driving direction of the movable-side electrode bar; a first guide joined to the other end of the bellows, the first guide having an outer circumferential portion in contact with a valley portion of the bellows structure and an inner circumferential portion in contact with the movable electrode bar, the first guide having a protrusion; a second guide joined to the movable-side end plate, the outer periphery of which contacts the valley portion of the bellows structure and the inner periphery of which contacts the movable-side electrode bar, and the second guide having a protrusion that can be fitted into the first guide; A vacuum valve comprising:
3. an insulating container whose interior is kept under vacuum and which has a fixed end plate and a movable end plate at both ends; a fixed electrode rod fixed to the fixed end plate and having a fixed contact joined to an end thereof; a movable electrode rod disposed on the movable end plate and having a movable contact joined to an end thereof, the movable contact being arranged so as to be able to come into contact with and separate from the fixed contact; a bellows having a bellows structure, one end of which is joined to the movable-side end plate and the other end of which is joined to the movable-side electrode bar, and which is expandable and contractible in the driving direction of the movable-side electrode bar; a thin plate ring having a U-shaped cross section or a divided body of the ring inserted into a valley portion of the bellows structure; A vacuum valve comprising:
4. The bellows has a multi-layer structure, The layers are not sealed apart from both ends of the multilayer structure, 4. The vacuum valve according to claim 1, wherein the layers are sealed at both ends of the multi-layer structure.
5. 2. The vacuum valve according to claim 1, wherein at least one of the valleys of the bellows structure and the outer periphery of the movable electrode rod is insulated.
6. 6. The vacuum interrupter according to claim 1, wherein the movable electrode rod is a rectangular pillar.
7. 3. The vacuum valve according to claim 2, wherein the first guide and the second guide are made of insulating material.
8. the movable electrode rod is a rectangular pillar, 8. The vacuum valve according to claim 2 or 7, wherein the cross section of the inner periphery of the first guide and the cross section of the inner periphery of the second guide have the same polygonal shape as the cross section of the movable electrode rod, which is a rectangular pillar.
9. 8. The vacuum valve according to claim 2, wherein the cross section of the outer periphery of the first guide and the cross section of the outer periphery of the second guide are polygonal.
10. a step of fitting together a plurality of cylindrical bodies having different diameters to form a multi-layered cylindrical body; forming a side wall of the multilayer cylindrical body into a bellows shape to produce a multilayer bellows having a bellows structure; sealing the layers at both ends of the multi-layer bellows; a step of arranging the multi-layer bellows so that a valley portion of the bellows structure of the multi-layer bellows contacts a movable electrode bar; A method for manufacturing a vacuum valve, comprising: