CN217933605U - Voltage-sharing insulating table - Google Patents
Voltage-sharing insulating table Download PDFInfo
- Publication number
- CN217933605U CN217933605U CN202220852891.3U CN202220852891U CN217933605U CN 217933605 U CN217933605 U CN 217933605U CN 202220852891 U CN202220852891 U CN 202220852891U CN 217933605 U CN217933605 U CN 217933605U
- Authority
- CN
- China
- Prior art keywords
- voltage
- sharing
- conducting ring
- conducting
- ring
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Insulating Bodies (AREA)
Abstract
The utility model relates to a fracture voltage-sharing device of multi-fracture circuit breaker, in particular to voltage-sharing insulating station. A voltage-sharing insulating table comprises a cast insulator which is cast and molded by epoxy resin, wherein the cast insulator is of a cylindrical structure, and a voltage-sharing capacitor string, a conducting ring and a conducting insert are cast inside the cast insulator; the upper end and the lower end of each voltage-sharing capacitor string are respectively connected with the corresponding conducting rings, and the conducting inserts are connected to one sides of the conducting rings, which are back to the voltage-sharing capacitor strings; the conducting ring is provided with a mounting hole, and the end part of the voltage-sharing capacitor string is fixedly connected with the conducting ring through a connecting screw penetrating through the mounting hole; the radial outer edge of the conducting ring is provided with a shielding bulge, and the shielding bulge forms an annular structure with a smooth curve cross section on one side of the conducting ring away from the voltage-sharing capacitor string or on two axial sides of the conducting ring and is used for balancing an electric field at the conducting ring. The utility model discloses can solve the inconvenient technical problem of being connected of voltage-sharing electric capacity cluster among the prior art and conducting ring.
Description
Technical Field
The utility model relates to a fracture voltage-sharing device of multi-fracture circuit breaker, in particular to voltage-sharing insulating station.
Background
The high-voltage vacuum breaking equipment gradually moves to the trend of high voltage and large current, and is generally realized by adopting a multi-fracture series connection mode. For example, the breaking technology of 126kV vacuum switchgear is mature at present, but the development is slow for high-grade vacuum switchgear, and the high-grade vacuum switchgear is often manufactured by connecting a plurality of 126kV vacuum switchgear in series and in parallel.
The voltage distribution of the individual fractures in a high voltage class vacuum switchgear manufactured by the series-parallel scheme is the focus of attention for a multi-fracture switchgear. Especially, 550kV vacuum circuit breaker, the condition that each fracture series voltage distributes unevenly is comparatively obvious, needs effectively to solve in order to guarantee the insulating properties and the reliability of multi-fracture circuit breaker. Patent document CN112837966A discloses an arc extinguish chamber structure, wherein a plurality of strings of equalizing capacitors are arranged outside the arc extinguish chamber to equalize the voltage of each fracture, the equalizing capacitors strings, a static end conductive part, a moving end conductive part and the arc extinguish chamber are cast in epoxy resin together, or the equalizing capacitors strings and a graphite connecting piece connected with a main shield cover on the arc extinguish chamber during assembly are cast in epoxy resin together, and then the end parts of the equalizing capacitors strings are embedded into mounting grooves uniformly distributed along the circumferential direction on the correspondingly arranged static end conductive part/moving end conductive part, so as to realize the connection between the equalizing capacitors strings and a circuit. However, the arc extinguishing chamber structure in the above patent document requires installation of the stationary-end conductive member and the moving-end conductive member and assembly with the arc extinguishing chamber during manufacturing, and is complicated in structure and inconvenient in assembly.
Patent document CN215342419U discloses a voltage-sharing insulating cylinder and a voltage-sharing capacitor string thereof, wherein the voltage-sharing capacitor string is poured in the insulating cylinder, conductive rings are welded at two ends of the voltage-sharing capacitor string, an insert is welded at one side of the conductive rings, which is opposite to the voltage-sharing capacitor string, the insert is exposed on the end face of the insulating cylinder, and can be conveniently connected with a vacuum arc extinguish chamber through the insert, and the structure is simple.
However, in order to ensure the electric field balance at the conductive ring, two ends of the voltage-sharing capacitor string in patent document CN215342419U are welded and fixed on corresponding side surfaces of the conductive ring, which is inconvenient for welding operation and easily affects assembly efficiency and production cost.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to provide a voltage-sharing insulating table to solve the inconvenient technical problem of being connected of voltage-sharing electric capacity cluster among the prior art and conducting ring.
In order to achieve the above object, the utility model provides a voltage-sharing insulating station's technical scheme is:
a voltage-sharing insulating table comprises a cast insulator which is cast and molded by epoxy resin, wherein the cast insulator is of a cylindrical structure, and a voltage-sharing capacitor string, a conducting ring and a conducting insert are cast inside the cast insulator; the upper end and the lower end of each voltage-sharing capacitor string are respectively connected with the corresponding conducting rings, and the conducting insert is connected to one side of each conducting ring, which is back to the voltage-sharing capacitor string; the conducting ring is provided with a mounting hole, and the end part of the voltage-sharing capacitor string is fixedly connected with the conducting ring through a connecting screw penetrating through the mounting hole; the radial outer edge of the conducting ring is provided with a shielding bulge, and the shielding bulge forms an annular structure with a smooth curve cross section on one side of the conducting ring away from the voltage-sharing capacitor string or on two axial sides of the conducting ring and is used for balancing an electric field at the conducting ring.
The beneficial effects of the above technical scheme are that, through setting up mounting hole and connecting screw, the conducting ring can conveniently be fixed with voltage-sharing capacitor cluster with the mode of screwed connection, and simultaneously, the shielding arch of radial outside edge can form the annular structure that the cross section is smooth curve in one side or the axial both sides that voltage-sharing capacitor cluster was kept away from to the conducting ring, smooth curve that smooth curve corresponds is protruding in the corresponding side of conducting ring, can play the equilibrium effect to the electric field of conducting ring department, the connecting screw who avoids setting up causes great influence to the electric field of conducting ring department, thereby realized the screwed connection of voltage-sharing capacitor cluster with the conducting ring under the circumstances of guaranteeing partial discharge barrier propterty, and convenient for connection, be favorable to improving packaging efficiency, and the production cost is reduced.
Further: the shielding bulges on the two axial sides of the conducting ring are smoothly connected, so that the radial outer edge of the conducting ring forms a smooth and expanded structure.
The technical scheme has the advantages that the electric field distribution of the radial outer edge of the conducting ring can be more balanced, and the partial discharge shielding effect is better.
Further: the parts of the shielding bulges protruding to the two axial sides of the conducting ring are symmetrically arranged along the axial direction of the conducting ring.
The technical scheme has the advantages that the design and the manufacture of the conducting ring can be facilitated, the front side and the back side do not need to be distinguished, and the assembly is more convenient.
Further, the method comprises the following steps: the cross section of the shielding protrusion is arc-shaped.
The technical scheme has the advantages that the arc-shaped shielding effect is better, the structure is simpler, and the manufacturing is convenient.
Further, the method comprises the following steps: the shielding protrusion is in smooth transition with the plate body of the conductive ring.
The technical scheme has the advantages that the sudden change surface can be prevented from being formed between the shielding protrusion and the plate main body, and partial discharge can be further controlled.
Further: the shielding protrusion is integrally formed with the plate body of the conductive ring.
The technical scheme further limited has the advantages that the shielding protrusion and the plate main body are integrally formed, so that the manufacturing is convenient, and the increase of local discharge amount can be avoided when the shielding protrusion and the plate main body are connected in a split manner.
Further: the head of the connecting screw is at least partially sunk into the side surface of the conductive ring.
The beneficial effect of the above-mentioned technical scheme who further prescribes a limit to is, can further reduce the influence of the increase of connecting screw to electric field distribution, and the reliability is better.
Further, the method comprises the following steps: any two adjacent voltage-sharing capacitors in the same voltage-sharing capacitor string are conductively connected through a connecting rod, each voltage-sharing capacitor is provided with a threaded hole, and the end part of the connecting rod is provided with an external thread.
The technical scheme has the advantages that any two adjacent voltage-sharing capacitors in the same voltage-sharing capacitor string are connected through the connecting rod in a threaded manner, connection is reliable, the interval between the two adjacent voltage-sharing capacitors can be prevented from changing when epoxy resin is poured, and the electric field is prevented from being uneven.
Further, the method comprises the following steps: the conductive inserts are arranged in a plurality of numbers, and the conductive inserts are uniformly distributed at intervals along the circumferential direction of the corresponding conductive ring.
The technical scheme has the advantages that the conductive inserts are uniformly distributed on the corresponding conductive rings at intervals, and the balance of current circulation paths can be improved.
Further, the method comprises the following steps: and the voltage-sharing capacitor strings are uniformly distributed at intervals along the circumferential direction of the cast insulator.
The technical scheme has the advantages that the electric field generated by each voltage-sharing capacitor string is distributed more uniformly, and the voltage-sharing effect is better.
Drawings
Fig. 1 is a schematic structural view of a voltage-sharing insulating table provided by the present invention;
FIG. 2 is a schematic diagram illustrating an assembly relationship of the voltage-sharing capacitor strings, the conductive rings and the conductive inserts in FIG. 1;
fig. 3 is a top view of fig. 2.
Description of the reference numerals: 1. pouring an insulator; 2. a voltage-sharing capacitor string; 21. a voltage-sharing capacitor; 22. a connecting rod; 3. conducting rings; 31. a plate main body; 32. a shielding projection; 4. a conductive insert; 5. and connecting screws.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more clear, the present invention is further described in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the invention, i.e., the described embodiments are only some, but not all embodiments of the invention. The components of the embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the invention, as presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. Based on the embodiment of the present invention, all other embodiments obtained by those skilled in the art without creative efforts belong to the protection scope of the present invention.
It is noted that, in the embodiments of the present invention, relational terms such as "first" and "second", and the like may be present only for distinguishing one entity or operation from another entity or operation without necessarily requiring or implying any actual such relationship or order between such entities or operations. Also, terms such as "comprises," "comprising," or any other variation thereof, which may be present, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, the statement that "comprises a component of 8230; \8230;" comprises an element of 8230; "etc. may occur does not exclude the presence of additional identical elements in the process, method, article, or apparatus that comprises the component.
In the description of the present invention, unless otherwise explicitly specified or limited, terms such as "mounted," "connected," and "connected" that may be present are to be construed broadly, e.g., as a fixed connection, a releasable connection, or an integral connection; can be mechanically or electrically connected; either directly or indirectly through intervening media, or may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood by those skilled in the art through specific situations.
In the description of the present invention, unless otherwise explicitly specified or limited, the term "provided" may be used in a broad sense, for example, the object of "provided" may be a part of the body, or may be arranged separately from the body and connected to the body, and the connection may be a detachable connection or a non-detachable connection. The specific meaning of the above terms in the present invention can be understood by those skilled in the art through specific situations.
The present invention will be described in further detail with reference to examples.
The utility model discloses in the embodiment 1 who provides a voltage-sharing insulating stage:
as shown in fig. 1 and 2, the voltage-sharing insulating stand includes a cast insulator 1, the cast insulator 1 is a cylindrical structure cast by epoxy resin, eight voltage-sharing capacitor strings 2 are disposed therein, and the upper end and the lower end of each voltage-sharing capacitor string 2 are electrically connected through a corresponding conductive ring 3.
Eight voltage-sharing capacitor strings 2 are evenly distributed along the circumferential interval of the cylinder body 1, so that the electric field in the cylinder body 1 is more balanced. Each voltage-sharing capacitor string 2 comprises a plurality of voltage-sharing capacitors 21, and any adjacent voltage-sharing capacitor 21 in the same voltage-sharing capacitor string 2 are in conductive connection through a connecting rod 22. During the concrete implementation, each voltage-sharing electric capacity 21's upside and downside are protruding to be equipped with the connection platform to each is connected the bench and all is provided with the internal thread, sets up the external screw thread at the both ends of each connective bar 22, with the connection platform threaded connection on the corresponding voltage-sharing electric capacity 21.
The two conducting rings 3 are consistent in structure and are respectively arranged at the upper end and the lower end of the voltage-sharing capacitor string 2. As shown in fig. 2 and 3, the conductive ring 3 has an overall ring-plate structure, and includes two portions, namely, a plate body 31 and a shielding protrusion 32. The shielding protrusions 32 are arranged on the radial outer edges of the two axial sides of the conducting ring 3, the shielding protrusions 32 form annular structures with circular arc-shaped cross sections on the two side surfaces of the conducting ring 3 respectively, and the shielding protrusions 32 on the two sides are connected smoothly, so that the radial outer edges of the conducting ring 3 form a smooth and expanded structure for balancing an electric field at the conducting ring 3. The cross section of the shielding protrusion 32 is arc-shaped, and when the shielding protrusion 32 and the plate main body 31 are manufactured, the shielding protrusion 32 and the plate main body 31 are integrally formed, so that the manufacturing is simple, an electric field generated at the edge of the conducting ring 3 can be balanced, the local discharge amount at the edge of the conducting ring 3 is further reduced, and the influence of the local discharge of the conducting ring 3 on the epoxy resin is reduced. Eight mounting holes are uniformly distributed on the plate main bodies 31 of the two conducting rings 3 at intervals, the uppermost voltage-sharing capacitors 21 in the voltage-sharing capacitor strings 2 are connected through the connecting screws 5 by the mounting holes on the conducting ring 3 on the upper side, and the lowermost voltage-sharing capacitors 21 in the voltage-sharing capacitor strings 2 are connected through the connecting screws 5 shown in fig. 3 by the mounting holes on the conducting ring 3 on the lower side. The head of the connecting screw 5 in fig. 1 and 2 is sunk into the conductive ring 3 and is therefore not shown.
To facilitate the electrically conductive connection of the two conducting rings 3 to the respective electrical members. In this embodiment, two conductive insert groups are provided, each of the two conductive insert groups is provided with a plurality of conductive inserts 4, wherein the conductive insert 4 in one conductive insert group is an upper conductive insert, is uniformly distributed on the upper conductive ring 3 at intervals, is fixedly connected with the upper conductive ring 3, and is used for being conductively connected with a corresponding electrical component on the upper side of the voltage-sharing insulating station; the conductive inserts 4 in the other group of conductive inserts are lower conductive inserts, are uniformly distributed on the conductive ring 3 at intervals, are fixedly connected with the conductive ring 3 at the lower side, and are used for being in conductive connection with corresponding electric parts at the lower side of the voltage-sharing insulating table. The conductive inserts and the conductive rings can be fixedly connected by welding and other modes.
When assembling the voltage-sharing insulating table, link together each voltage-sharing electric capacity 21 and connective bar 22 earlier to form voltage-sharing electric capacity cluster 2, then with the conducting ring 3 of upside with each voltage-sharing electric capacity cluster 2 in the voltage-sharing electric capacity 21 of top be connected through the connecting screw 5 that passes corresponding mounting hole, with the conducting ring 3 of downside and each voltage-sharing electric capacity cluster 2 in the voltage-sharing electric capacity 21 of bottom be connected through the connecting screw 5 that passes corresponding mounting hole, the re-than is respectively connected electrically conductive inserts and the conducting ring 3 of upside, electrically conductive inserts is connected with the conducting ring 3 of downside down. And then, pouring epoxy resin on each voltage-sharing capacitor string 2 and the two conducting rings 3, and curing the epoxy resin to form a complete voltage-sharing insulating table.
The utility model provides a voltage-sharing insulating stand is provided with a cylindrical casting insulator 1 which is formed by casting epoxy resin, a plurality of voltage-sharing capacitor strings 2 are arranged in the casting insulator 1, a plurality of voltage-sharing capacitors 21 in each voltage-sharing capacitor string 2 are electrically connected in series, the upper end and the lower end of each voltage-sharing capacitor string 2 are electrically connected through a conducting ring 3, and the parallel conductive connection of each voltage-sharing capacitor string 2 is realized; and the conducting ring 5 is electrically connected with the corresponding electric element through the conducting insert 4, so that the voltage of each fracture of the multi-port circuit breaker can be balanced. The radial outer edge of the conducting ring 3 is provided with the smooth shielding protrusion 32, so that an electric field generated at the edge of the conducting ring 3 can be balanced, and the influence of the arrangement of the connecting screw 5 on the local discharge quantity at the conducting ring 3 is avoided, so that the influence on the insulating property of epoxy resin and the reliability of the circuit breaker is reduced or avoided.
The utility model discloses in provide a voltage-sharing insulating stage's embodiment 2:
the present embodiment is different from embodiment 1 in that, in embodiment 1, the shield projection 32 is integrally formed with the plate main body 31. In the present embodiment, the shield projection is manufactured separately from the plate main body and is welded to the plate main body.
The utility model discloses in the embodiment 3 who provides a voltage-sharing insulating stage:
the present embodiment is different from embodiment 1 in that, in embodiment 1, the shielding protrusions 32 are disposed on both axial sides of the conductive ring 3. In the embodiment, the conducting ring 3 is provided with the shielding protrusion 32 only on the side away from the voltage-sharing capacitor string 2, and can also shield the connecting screw 5.
In addition, in the above-mentioned embodiment, the parts of the shielding protrusions 32 protruding to the two axial sides of the conductive ring 3 are symmetrically arranged along the axial direction of the conductive ring 3, and in other embodiments, the parts of the shielding protrusions 32 protruding to the two axial sides of the conductive ring 3 may be in an asymmetric form, for example, the protrusion height of the conductive ring 3 on the side far away from the grading capacitor string 2 is greater than the protrusion height of the conductive ring 3 on the side near the grading capacitor string 2.
Further, in the above-mentioned embodiment, the cross section of the shielding protrusion 32 is circular arc, but in other embodiments, the cross section of the shielding protrusion 32 may be other curved shapes, such as a smooth curve in the form of a parabola.
The above description is only for the preferred embodiment of the present invention, and the present invention is not limited thereto, the protection scope of the present invention is defined by the claims, and all structural changes equivalent to the contents of the description and drawings of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A voltage-sharing insulating table comprises a pouring insulator (1) which is formed by pouring epoxy resin, wherein the pouring insulator (1) is of a cylindrical structure, and a voltage-sharing capacitor string (2), a conducting ring (3) and a conducting insert (4) are poured inside the pouring insulator; the upper end and the lower end of each voltage-sharing capacitor string (2) are respectively connected with the corresponding conducting ring (3), and the conducting insert (4) is connected to one side of each conducting ring (3) back to the voltage-sharing capacitor string (2); the voltage-sharing capacitor is characterized in that a mounting hole is formed in the conducting ring (3), and the end part of the voltage-sharing capacitor string (2) is fixedly connected with the conducting ring (3) through a connecting screw (5) penetrating through the mounting hole; the radial outer edge of the conducting ring (3) is provided with a shielding protrusion (32), and the shielding protrusion (32) forms an annular structure with a smooth curve cross section on one side of the conducting ring (3) far away from the voltage-sharing capacitor string (2) or on two axial sides of the conducting ring (3) and is used for balancing an electric field at the conducting ring (3).
2. A voltage grading insulation station according to claim 1, characterized in that the shielding protrusions (32) on both axial sides of the conductive ring (3) are smoothly connected such that the radially outer edges of the conductive ring (3) form a smoothly expanding structure.
3. A voltage grading insulation station according to claim 2, characterized in that the parts of the shielding protrusions (32) protruding towards the axial sides of the conductive ring (3) are arranged symmetrically in the axial direction of the conductive ring (3).
4. A voltage grading insulation table according to claim 2 or 3, characterized in that the cross-section of said shielding protrusion (32) is circular arc shaped.
5. A voltage grading insulation station according to claim 2 or 3, characterized in that said shielding protrusion (32) is in a smooth transition with the plate body (31) of the electrically conductive ring (3).
6. A voltage grading insulation station according to claim 2 or 3, characterized in that said shielding protrusion (32) is formed integrally with the plate body (31) of the conductive ring (3).
7. A voltage grading insulation table according to claim 1 or 2 or 3, characterized in that the head of the connection screw (5) is at least partly sunk into the side of the conductive ring (3).
8. A voltage-sharing insulating table according to claim 1, 2 or 3, characterized in that any two adjacent voltage-sharing capacitors (21) in the same voltage-sharing capacitor string (2) are electrically connected through a connecting rod (22), each voltage-sharing capacitor (21) is provided with a threaded hole, and the end of the connecting rod (22) is provided with an external thread.
9. A voltage-sharing insulating table according to claim 1, 2 or 3, characterized in that the conductive inserts (4) are provided in plurality, and each conductive insert (4) is uniformly distributed at intervals along the circumference of the corresponding conductive ring (3).
10. A grading insulation station according to claim 1, 2 or 3, characterized in that the grading capacitor strings (2) are evenly spaced along the circumference of the cast insulation (1).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202220852891.3U CN217933605U (en) | 2022-04-13 | 2022-04-13 | Voltage-sharing insulating table |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202220852891.3U CN217933605U (en) | 2022-04-13 | 2022-04-13 | Voltage-sharing insulating table |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN217933605U true CN217933605U (en) | 2022-11-29 |
Family
ID=84176056
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202220852891.3U Active CN217933605U (en) | 2022-04-13 | 2022-04-13 | Voltage-sharing insulating table |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN217933605U (en) |
-
2022
- 2022-04-13 CN CN202220852891.3U patent/CN217933605U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP3210221B1 (en) | Film capacitor | |
| CN217933605U (en) | Voltage-sharing insulating table | |
| CN202678202U (en) | Serial structure of a high-voltage vacuum arc extinguish chamber | |
| CN207250891U (en) | A kind of ultra-micro high-density data line connector | |
| CN100367439C (en) | Active part for a surge arrester | |
| CN103515918A (en) | Voltage-sharing cover assembly | |
| CN215342419U (en) | Voltage-sharing insulating cylinder and voltage-sharing capacitor string thereof | |
| CN105226851A (en) | A kind of stator improving the non-homogeneous fluting of circumference of nuclear power generator insulation life | |
| CN201438604U (en) | Improved multigap metal-ceramic gas discharge tube with external trigger termination | |
| KR20200119015A (en) | Contact assembly of vacuum interrupter | |
| CN205039629U (en) | Improve nuclear power and send out officious announcement grooved stator of circumference in motor insulation life -span | |
| CN112837966B (en) | Arc extinguish chamber structure | |
| CN202307531U (en) | Voltage sharing capacitor for multibreak vacuum circuit breaker | |
| CN112435815A (en) | High-strength suspension insulator for ultra-high voltage transmission line | |
| CN215342427U (en) | Arc extinguish chamber and multi-fracture switch equipment | |
| CN111725728B (en) | Gas insulated switchgear and cartridge assembly | |
| CN215815424U (en) | Spacer assembly for a gas insulation system and gas insulation system | |
| CN111900660A (en) | Gas insulation barrel assembly and insulation supporting plate thereof | |
| CN213366366U (en) | Structure for preventing epoxy resin of multi-cylinder ignition coil from cracking | |
| CN216749605U (en) | Cylindrical capacitor with collinear core and shell axis | |
| CN207116208U (en) | A kind of inside new structure of middle voltage current transformer | |
| CN216750359U (en) | High-voltage miniaturized inner cone socket | |
| CN215342278U (en) | Electronic voltage transformer | |
| CN109215996B (en) | Ground isolation energy supply transformer | |
| CN102915864B (en) | Outdoor on-post wide-voltage vacuum breaker |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |