Insulating sleeve for vacuum circuit breaker and vacuum circuit breaker

Abstract

The utility model relates to the technical field of electric switches, in particular to an insulating sleeve for a vacuum circuit breaker and the vacuum circuit breaker. The vacuum circuit breaker comprises a vacuum arc-extinguishing chamber and an insulation pull rod, one end of the vacuum arc-extinguishing chamber is provided with an insulation sleeve, the insulation sleeve comprises a cylindrical hollow sleeve body, the sleeve body comprises an outer insulation wall and an inner insulation wall, the outer insulation wall is provided with an insulation wrapping layer, and the inner insulation wall is provided with an inner insulation wrapping layer. The insulating wrapping layer comprises an insulating tape and insulating protrusions arranged on the outer wall of the insulating tape, and the insulating tape is spirally wound on the outer insulating wall to form a spiral butt joint seam and spiral protrusions. According to the insulating sleeve provided by the utility model, the creepage distance of current can be prolonged through the arrangement of the spiral butt joint seams and the spiral umbrella skirts, so that the electrical insulation performance of the insulating sleeve can be improved.

Description

Technical Field

[0001] This utility model relates to the field of electrical switch technology, and in particular to an insulating sleeve for a vacuum circuit breaker and a vacuum circuit breaker. Background Technology

[0002] A circuit breaker is a switching device capable of closing, carrying, and interrupting current under normal circuit conditions and closing, carrying, and interrupting current under abnormal circuit conditions within a specified time. Vacuum circuit breakers are named for their high-vacuum arc-extinguishing medium and the insulating medium between the contacts after arc extinguishing. Vacuum circuit breakers have advantages such as small size, light weight, suitability for frequent operation, and maintenance-free arc extinguishing, making them widely used in power distribution networks. A vacuum circuit breaker mainly consists of a vacuum interrupter, insulating sleeve, operating mechanism, and insulating rod. When the operating mechanism operates, the force is transmitted to the moving contact of the vacuum interrupter through the insulating rod, causing the moving contact to separate or close from the stationary contact, thereby controlling the circuit's on / off state. The insulating sleeve connects to the vacuum interrupter and provides electrical insulation throughout the process, preventing current leakage or short circuits. To enhance the electrical insulation performance of the insulating sleeve to meet usage requirements, existing technologies typically employ annular silicone rubber skirts on the outer insulating wall of the insulating sleeve to increase its electrical insulation performance.

[0003] Chinese utility model patent document with authorization announcement number CN21906006U and authorization announcement date of 2023 / 05 / 30 discloses an insulating sleeve for an outdoor vacuum circuit breaker. The insulating sleeve includes an epoxy cylinder and a silicone rubber sleeve wrapped around the outer insulating wall of the epoxy cylinder, and the silicone rubber sleeve is provided with an annular umbrella skirt.

[0004] The insulating sleeve in this patent achieves its insulation performance and reduces flashover failures by using a silicone rubber sleeve on its outer insulating wall and skirts on the silicone rubber sleeve. Although the specific wrapping process of the silicone rubber sleeve on the outer insulating wall of the epoxy cylinder is not specified, based on existing products on the market, most products use adhesives or other bonding agents to attach the silicone rubber sleeve to the outer insulating wall of the epoxy cylinder. During the bonding process, a straight seam is formed at the joint between the two sides of the silicone rubber sleeve and the two ends of the skirts on the silicone rubber sleeve. During the use of the insulating sleeve, current easily flows along this seam, thus shortening the current creepage distance and reducing the insulation performance of the insulating sleeve. Utility Model Content

[0005] The purpose of this utility model is to provide an insulating sleeve for vacuum circuit breakers, in order to solve the problem in the prior art that the creepage distance of the current is short due to the easy formation of butt joints when pasting silicone rubber sleeves, which in turn leads to a reduction in the insulation performance of the insulating sleeve.

[0006] The purpose of this utility model is also to provide a vacuum circuit breaker to solve the problem in the prior art that the creepage distance of the current is short due to the easy formation of butt joints when pasting silicone rubber sleeves, which in turn leads to a reduction in the insulation performance of the insulating sleeve.

[0007] To solve the above problems, the insulating sleeve for the vacuum circuit breaker of this utility model adopts the following technical solution:

[0008] An insulating sleeve for a vacuum circuit breaker includes a cylindrical hollow sleeve body. The sleeve body includes an outer insulating wall and an inner insulating wall. An insulating sheath is provided on the outer insulating wall. The insulating sheath includes an insulating strip and insulating protrusions provided on the outer wall of the insulating strip. The insulating strip is spirally wound on the outer insulating wall to form a spiral butt joint and spiral protrusions.

[0009] Furthermore, the insulating protrusion forms a gradient with a thicker bottom and thinner edges relative to the insulating strip.

[0010] Furthermore, the gradient shape has an isosceles triangular cross-section in the direction perpendicular to the insulating strip.

[0011] Furthermore, the insulating protrusion is disposed at the center in the width direction of the insulating strip.

[0012] Furthermore, the insulating tape is bonded to the outer insulating wall of the insulating sleeve.

[0013] Furthermore, the insulating layer is a silicone rubber insulating layer.

[0014] Furthermore, the inner insulating wall is provided with spiral grooves to form an uneven structure and extend the creepage distance.

[0015] Furthermore, the spiral groove is an internal thread.

[0016] Furthermore, both ends of the sleeve body are provided with connecting flanges.

[0017] Beneficial Effects: This invention relates to an improved insulating sleeve for vacuum circuit breakers. Based on existing insulating sleeve structures, this invention particularly improves upon the annular awnings on the outer insulating wall. When the insulating sheath is wound and arranged on the outer insulating wall of the insulating sleeve, the spiral joint formed by the winding of the insulating tape and the spirally arranged insulating protrusions can both extend the current creepage distance. This helps avoid the formation of straight joints due to the joint, thus preventing the reduction in electrical insulation performance of the insulating sleeve due to a short creepage distance, thereby improving the electrical insulation performance of the insulating sleeve.

[0018] To solve the above problems, the vacuum circuit breaker of this utility model adopts the following technical solution:

[0019] A vacuum circuit breaker includes a vacuum interrupter and an insulating tie rod. One end of the vacuum interrupter is provided with an insulating sleeve. The insulating sleeve includes a cylindrical hollow sleeve body, an outer insulating wall and an inner insulating wall. An insulating cladding is provided on the outer insulating wall. The insulating cladding includes an insulating strip and insulating protrusions provided on the outer wall of the insulating strip. The insulating strip is spirally wound on the outer insulating wall to form a spiral butt joint and spiral protrusions.

[0020] Furthermore, the insulating protrusion forms a gradient with a thicker bottom and thinner edges relative to the insulating strip.

[0021] Furthermore, the gradient shape has an isosceles triangular cross-section in the direction perpendicular to the insulating strip.

[0022] Furthermore, the insulating protrusion is disposed at the center in the width direction of the insulating strip.

[0023] Furthermore, the insulating tape is bonded to the outer insulating wall of the insulating sleeve.

[0024] Furthermore, the insulating layer is a silicone rubber insulating layer.

[0025] Furthermore, the inner insulating wall is provided with spiral grooves to form an uneven structure and extend the creepage distance.

[0026] Furthermore, the spiral groove is an internal thread.

[0027] Furthermore, both ends of the sleeve body are provided with connecting flanges.

[0028] Beneficial Effects: This invention relates to an improved vacuum circuit breaker. Based on existing technology, this invention particularly improves the annular shed on the outer layer of the insulating sleeve. When the insulating sheath is wound and arranged on the outer insulating wall of the insulating sleeve, the spiral joint formed by the winding of the insulating tape and the spirally arranged insulating protrusions can both extend the current creepage distance. This helps to avoid the formation of straight joints due to the joint, thereby preventing the reduction of the electrical insulation performance of the insulating sleeve due to a short creepage distance, thus improving the electrical insulation performance of the insulating sleeve. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of an embodiment of the insulating sleeve for a vacuum circuit breaker according to the present invention.

[0030] Figure 2 forFigure 1 A schematic diagram of a half-section structure;

[0031] Figure 3 This is a schematic diagram of the structure of the insulating sleeve for the vacuum circuit breaker of this utility model during use.

[0032] In the diagram: 1. Sleeve body; 2. Insulating tape; 3. Insulating protrusion; 4. Spiral butt joint; 5. Isosceles triangular cross section; 6. Internal thread; 7. Connecting flange; 8. Vacuum interrupter; 9. Insulating tie rod. Detailed Implementation

[0033] The features and performance of this utility model will be further described in detail below with reference to the embodiments.

[0034] An embodiment of the insulating sleeve for the vacuum circuit breaker of this utility model is as follows:

[0035] The insulating sleeve for vacuum circuit breakers of this invention utilizes the principle of improving insulation performance by extending the creepage distance. The original annular skirt is improved by spiral protrusions, which further enhances the insulation performance of the insulating sleeve.

[0036] As a basic solution, such as Figures 1-3 As shown, the insulating sleeve for a vacuum circuit breaker of this utility model includes a cylindrical hollow sleeve body 1. The sleeve body 1 includes an outer insulating wall and an inner insulating wall. The main function of the insulating sleeve is to provide electrical insulation, ensuring that current does not flow through unexpected paths. In a vacuum circuit breaker, the insulating sleeve can effectively isolate live parts, prevent the generation and spread of electric arcs, and thus protect the safety of equipment and personnel. The outer insulating wall mainly insulates against the external environment of the vacuum circuit breaker, such as moisture and dirt in the atmosphere. The inner insulating wall mainly insulates against the conductive parts inside the vacuum circuit breaker, such as moving contacts and stationary contacts. The outer insulating wall is provided with an insulating sheath, which includes an insulating strip 2 and insulating protrusions 3 on the outer wall of the insulating strip 2. The insulating strip 2 is spirally wound on the outer insulating wall to form a spiral butt joint 4 and spiral protrusions. The insulating strip 2 has a certain degree of flexibility, allowing it to be wound around the outer insulating wall of the insulating sleeve to form... The spiral joint 4 and spiral protrusions create a longer current creepage distance compared to a straight joint. The spiral protrusions also extend the current creepage distance. Furthermore, the spiral umbrella skirt design has a self-cleaning function, as rainwater and other impurities can more easily flow down the spiral line, carrying away surface contaminants. This helps maintain the cleanliness of the outer insulation wall of the insulating sleeve, reduces maintenance costs, and further minimizes the problem of decreased insulation performance due to contamination, thereby improving the electrical insulation performance of the insulating sleeve.

[0037] As a preferred implementation method, such as Figures 1-2 As shown, the insulating protrusion 3 forms a gradient shape relative to the insulating strip 2, thicker at the bottom and thinner at the edges. The thicker design of the insulating protrusion 3 near the insulating strip 2 provides better mechanical support and electrical insulation, preventing cracks or even breakage at the bottom under external force, which would affect the electrical insulation performance of the insulating sleeve. The gradient shape has an isosceles triangular cross-section 5 perpendicular to the insulating strip 2. The thickness transition from thick at the bottom to thin at the edges forms a triangular cross-section, and this isosceles triangular arrangement ensures a uniform electric field distribution at the gradient shape, helping to reduce the phenomenon of excessively strong local electric fields and lowering the risk of insulation breakdown due to uneven electric field, thereby improving the service life and safety of the insulating sleeve.

[0038] As a preferred implementation method, such as Figure 1 As shown, the insulating protrusion 3 is disposed in the middle of the width direction of the insulating strip 2. The insulating strip 2 is spirally wound around the outer insulating wall of the insulating sleeve. The insulating protrusion 3 is disposed in the middle of the width direction of the insulating strip 2 to ensure that the distance between the insulating protrusions 3 after winding is uniform, thereby making the electric field distribution uniform, reducing the risk of insulation breakdown, and improving the electrical insulation performance of the insulating sleeve.

[0039] In a preferred embodiment, the insulating tape 2 is bonded to the outer insulating wall of the insulating sleeve. This bonding ensures that the insulating sheath and the outer insulating wall of the insulating sleeve are tightly bonded together to form an integral structure. This tight bond helps prevent moisture, dust, and other impurities from entering between the insulating sheath and the outer insulating wall, thereby maintaining the stability of the electrical insulation performance of the insulating sleeve. Furthermore, the bonding process is relatively simple and does not require complex processing equipment and technology, which helps reduce manufacturing costs and improve production efficiency. In other embodiments, the insulating tape 2 and the outer insulating wall of the insulating sleeve can be bonded together using an injection molding process. Although the injection molding process is more complex than bonding, it can still achieve the purpose of a tight bond between the insulating tape 2 and the outer insulating wall of the insulating sleeve.

[0040] In a preferred embodiment, the insulating layer is a silicone rubber insulating layer. Silicone rubber has excellent insulation properties and a high resistivity, which can effectively block the flow of current. Silicone rubber can also maintain stable performance in outdoor environments for a long time and has good hydrophobicity and anti-fouling properties. It is not easily affected by natural factors such as sunlight and rain, and has strong anti-aging properties, thereby extending the service life of the insulating sleeve. In addition, silicone rubber also has good elasticity and flexibility, which allows it to better fit and wrap around the outer insulating wall of the insulating sleeve. In other embodiments, when the insulating layer and the insulating sleeve are integrally molded, epoxy resin can also be used. Epoxy resin is also a commonly used insulating material for insulating sleeves in vacuum circuit breakers. Epoxy resin also has excellent mechanical strength, aging resistance, and good insulation properties.

[0041] As a preferred implementation method, such as Figures 2-3 As shown, the inner insulating wall is provided with a spiral groove to form a concave-convex structure and extend the creepage distance. This is consistent with the principle of designing the outer insulating wall as a spiral-shaped gradient, both of which further improve the electrical insulation performance of the insulating sleeve by increasing the current flow path, i.e., the creepage distance. The spiral groove design not only extends the current flow path but also optimizes space utilization. Because the spiral groove structure is relatively compact and is formed on the side wall of the insulating sleeve, it will not interfere with the insulating tie rod 9 or other components installed inside the insulating sleeve. The spiral groove is an internal thread 6. As a type of spiral groove, the internal thread 6 also serves to extend the current flow path and optimize space. Designing it as an internal thread 6 facilitates the use of injection molding during the processing of the insulating sleeve, allowing the sleeve body 1, the inner insulating wall, and the internal thread 6 to be integrally formed and easy to demold. Furthermore, threads have a high degree of standardization in existing technology, so designing it as an internal thread 6 also helps to improve the convenience and accuracy of production. In other embodiments, the spiral groove can use a spiral protrusion structure. In actual use, attention should be paid to the height of the protrusion to avoid interference with other internal components. The spiral protrusion can also achieve the purpose of extending the current flow path and enhancing insulation performance.

[0042] As a preferred implementation method, such as Figure 3As shown, both ends of the sleeve body 1 are provided with connecting flanges 7. One end of the insulating sleeve can be connected to the vacuum interrupter 8 through the connecting flange 7 to prevent current leakage through unexpected paths, thereby ensuring the electrical safety of the vacuum circuit breaker. The other end is connected to the insulating tie rod 9 through threads, and the connecting flange 7 on its end face is usually connected to the operating mechanism. The connecting flanges 7 at both ends of the insulating sleeve can increase the connection area, thereby making the connection between the two more stable and helping to improve the overall reliability of the circuit breaker. It can effectively prevent loosening or falling off due to vibration or external impact. The corresponding connecting flanges 7 can be connected by bolts. Bolted connections have the advantages of simple installation and easy disassembly, and bolts have a high degree of standardization and low procurement cost.

[0043] The specific usage process of the insulating sleeve for the vacuum circuit breaker of this utility model is as follows: Figure 3 As shown, one end of the insulating sleeve is connected to the end face of the vacuum interrupter 8 via the connecting flange 7 and bolts, so that the insulating sleeve can play the role of insulation and support. Then, the insulating rod 9 extends from the other end of the insulating sleeve and is connected to the conductive rod of the vacuum interrupter 8.

[0044] The embodiments of the vacuum circuit breaker of this utility model are as follows:

[0045] A vacuum circuit breaker includes a vacuum interrupter 8 and an insulating tie rod 9. One end of the vacuum interrupter 8 is provided with an insulating sleeve, wherein an embodiment of the insulating sleeve has been described above and will not be repeated here.

[0046] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. The patent protection scope of the present utility model shall be determined by the claims. Similarly, any equivalent structural changes made based on the description and drawings of the present utility model shall also be included within the protection scope of the present utility model.

Claims

1. An insulating sleeve for a vacuum circuit breaker, comprising a cylindrical hollow sleeve body, the sleeve body comprising an outer insulating wall and an inner insulating wall, characterized in that, The outer insulating wall is provided with an insulating cladding layer, which includes an insulating strip and insulating protrusions on the outer wall of the insulating strip. The insulating strip is spirally wound on the outer insulating wall to form a spiral butt joint and spiral protrusions.

2. The insulating sleeve for a vacuum circuit breaker according to claim 1, characterized in that, The insulating protrusion forms a gradient with a thicker bottom and thinner edges relative to the insulating strip.

3. The insulating sleeve for a vacuum circuit breaker according to claim 2, characterized in that, The gradient shape has an isosceles triangular cross-section in the direction perpendicular to the insulating strip.

4. The insulating sleeve for a vacuum circuit breaker according to claim 2, characterized in that, The insulating protrusion is located at the middle of the insulating strip in the width direction.

5. The insulating sleeve for a vacuum circuit breaker according to claim 1, characterized in that, The insulating tape is bonded to the outer insulating wall of the insulating sleeve.

6. The insulating sleeve for a vacuum circuit breaker according to any one of claims 1-5, characterized in that, The insulating layer is a silicone rubber insulating layer.

7. The insulating sleeve for a vacuum circuit breaker according to claim 1, characterized in that, The inner insulating wall is provided with spiral grooves to form an uneven structure and extend the creepage distance.

8. The insulating sleeve for a vacuum circuit breaker according to claim 7, characterized in that, The spiral groove is an internal thread.

9. The insulating sleeve for a vacuum circuit breaker according to claim 1, characterized in that, Both ends of the sleeve body are provided with connecting flanges.

10. A vacuum circuit breaker, comprising a vacuum interrupter and an insulating tie rod, wherein one end of the vacuum interrupter is provided with an insulating sleeve, characterized in that, The insulating sleeve is the insulating sleeve described in any one of claims 1-9.

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