A sleeve with electromagnetic shielding function
By introducing a shielding layer into the insulating bushing, the problem of the lack of electromagnetic shielding in existing bushings is solved, which achieves electromagnetic interference suppression and improved data accuracy, and simplifies the production process.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- GUANGDONG SIHUI INSTR TRANSFORMER WORKS
- Filing Date
- 2025-09-23
- Publication Date
- 2026-07-03
AI Technical Summary
The existing insulating bushings lack electromagnetic shielding design, making the monitoring instruments susceptible to strong electromagnetic interference, resulting in problems such as data distortion, lack of range versatility, electromagnetic radiation, and leakage reactance of the current booster.
A shielding layer is introduced into the insulating sleeve. The shielding layer is set on the inner wall of the inner insulating structure, the outer wall of the outer insulating structure, or between the two. It is connected to the insulating structure by means of integral molding or split molding. The shielding layer is a grid structure or braided structure made of conductive material and is encapsulated by the insulating layer. The ground wire is grounded to achieve electromagnetic shielding.
It effectively suppresses electromagnetic interference, improves the electromagnetic shielding capability of the bushing, ensures data accuracy and range versatility, reduces electromagnetic radiation and current booster leakage reactance, and simplifies the production process.
Smart Images
Figure CN120932975B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of current transformer technology, and more specifically, to a bushing with electromagnetic shielding function. Background Technology
[0002] Insulating bushings are key components used to support conductors and maintain electrical insulation, and are widely used in outdoor overhead power transmission systems and indoor current transformers. While maintaining conductor stability, they also need to withstand the effects of various environmental factors, such as:
[0003] Outdoor insulating sleeves need to withstand the effects of sun and rain, temperature changes and chemical corrosion over a long period of time, while also bearing the mechanical loads of the conductors in both vertical and horizontal directions.
[0004] Although the indoor insulating sleeve is in a less harsh environment than the outdoor environment, it still needs to cope with the effects of vibration, temperature changes and strong electric fields.
[0005] Furthermore, existing insulating bushings generally lack electromagnetic shielding design, making monitoring instruments susceptible to strong electromagnetic interference, resulting in problems such as data distortion, lack of range versatility, electromagnetic radiation, and high leakage reactance of the current booster. Therefore, how to enhance the electromagnetic shielding capability of insulating bushings to suppress electromagnetic interference while retaining the original insulation and support functions of the insulator is the technical problem to be solved in this application. Summary of the Invention
[0006] The summary section introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. The summary section of this invention is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.
[0007] To at least partially solve the above problems, the present invention provides a sleeve with electromagnetic shielding function, comprising: an inner insulating structure and an outer insulating structure, wherein the inner insulating structure and the outer insulating structure are connected to form a sleeve, and further comprising a shielding layer disposed on the inner wall of the inner insulating structure, and / or on the outer wall of the outer insulating structure, and / or between the inner insulating structure and the outer insulating structure.
[0008] Preferably, the shielding layer is disposed on the inner wall of the inner insulating structure, the distance between the two ends of the inner insulating structure is d, and the distance between the two ends of the shielding layer is L, where d > L.
[0009] Preferably, the shielding layer is disposed on the outer wall of the outer insulating structure, the distance between the two ends of the outer insulating structure is D, and the distance between the two ends of the shielding layer is L, where D > L.
[0010] Preferably, the shielding layer is disposed between the inner insulating structure and the outer insulating structure, the distance between the two ends of the inner insulating structure is d, the distance between the two ends of the outer insulating structure is D, and the distance between the two ends of the shielding layer is L, where D = d > L.
[0011] Preferably, a first groove is provided on the outer wall of the inner insulating structure, the shielding layer is disposed in the first groove, the inner wall of the outer insulating structure is connected to the outer wall of the inner insulating structure, and the shielding layer is encapsulated in the first groove.
[0012] Preferably, a second groove is provided on the inner wall of the outer insulating structure, the shielding layer is disposed in the second groove, the inner wall of the outer insulating structure is connected to the outer wall of the inner insulating structure, and the shielding layer is encapsulated in the second groove.
[0013] Preferably, the shielding layer is a first shielding layer, which is a mesh structure made of conductive material.
[0014] Preferably, the shielding layer is a second shielding layer, which is a mesh structure woven from conductive material, and the warp and weft threads of the second shielding layer are wrapped with a winding material made of conductive material, the conductive material of which is different from the conductive material of the second shielding layer.
[0015] Preferably, the shielding layer is a third shielding layer, and a fixing ring is provided on the third shielding layer, which is fixed in the first groove by the fixing ring.
[0016] Preferably, the retaining ring is made of a material with heat-shrinkable properties, and the third shielding layer is arranged along the axial direction of the sleeve.
[0017] Compared with the prior art, the present invention has at least the following beneficial effects:
[0018] Through the above structural design, the shielding layer can be encapsulated between the inner and outer insulation structures to prevent contact with the external environment. When the sleeve is made of epoxy resin, the shielding layer and part of the ground wire can be molded together with the sleeve in one step using a mold, thereby achieving the production of a sleeve with electromagnetic shielding function while ensuring the simplest production process.
[0019] The sleeve with electromagnetic shielding function described in this invention, other advantages, objectives and features of this invention will be partly apparent from the following description, and partly understood by those skilled in the art through study and practice of this invention. Attached Figure Description
[0020] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:
[0021] Figure 1 This is a front view of the sleeve with electromagnetic shielding function described in this invention.
[0022] Figure 2 A cross-sectional view showing the shielding layer positioned between the inner and outer insulation structures.
[0023] Figure 3 This is a schematic diagram of the first shielding layer inside the sleeve.
[0024] Figure 4 This is a partial schematic diagram of the first shielding layer inside the sleeve.
[0025] Figure 5 This is a schematic diagram of the second shielding layer inside the sleeve.
[0026] Figure 6 This is a partial schematic diagram of the second shielding layer inside the sleeve.
[0027] Figure 7 This is a schematic diagram of the third shielding layer.
[0028] Figure 8 This is a schematic diagram of the shrinkage process of the third shielding layer.
[0029] In the diagram: 100 sleeve, 1 inner insulation structure, 2 outer insulation structure, 3 shielding layer, 4 first shielding layer, 5 second shielding layer, 51 winding material, 6 third shielding layer, 61 fixing ring. Detailed Implementation
[0030] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments, so that those skilled in the art can implement it based on the description.
[0031] It should be understood that terms such as “having,” “comprising,” and “including” as used herein do not exclude the presence or addition of one or more other elements or combinations thereof.
[0032] like Figures 1-8 As shown, the present invention provides a sleeve with electromagnetic shielding function, comprising: an inner insulating structure 1 and an outer insulating structure 2, wherein the inner insulating structure 1 and the outer insulating structure 2 are connected to form a sleeve 100, and further comprising a shielding layer 3, wherein the shielding layer 3 is disposed on the inner wall of the inner insulating structure 1, and / or on the outer wall of the outer insulating structure 2, and / or between the inner insulating structure 1 and the outer insulating structure 2, wherein a ground wire is disposed on the shielding layer 3, the ground wire passing through the sleeve 100 and extending to the outside of the sleeve 100 to be grounded.
[0033] When the shielding layer 3 is disposed on the inner wall of the inner insulating structure 1, the inner insulating structure 1 and the outer insulating structure 2 are integrally formed into a sleeve 100. The distance between the two ends of the inner insulating structure 1 is d, and the distance between the two ends of the shielding layer 3 is L, where d > L, so that the two ends of the shielding layer 3 do not extend to the outside of the inner insulating structure 1. It should be noted that because the shielding layer 3 is disposed on the inner wall of the inner insulating structure 1, an insulating layer needs to be disposed on the shielding layer 3. The shielding layer 3 is encapsulated (i.e., the shielding layer 3 is sealed and installed on the inner wall of the inner insulating structure 1 through processes such as injection molding, coating or molding) by the insulating layer. Although an additional insulating layer is required and the construction process is more complicated than the following embodiments, the implementation method of disposing of the shielding layer 3 on the inner wall of the inner insulating structure 1 should not be excluded from the scope of protection.
[0034] When the shielding layer 3 is disposed on the outer wall of the outer insulating structure 2, the inner insulating structure 1 and the outer insulating structure 2 are integrally formed into a sleeve 100. The distance between the two ends of the outer insulating structure 2 is D, and the distance between the two ends of the shielding layer 3 is L, where D > L, so that the two ends of the shielding layer 3 do not extend to the outside of the outer insulating structure 2. It should be noted that because the shielding layer 3 is disposed on the outer wall of the outer insulating structure 2, an insulating layer needs to be disposed on the shielding layer 3 to encapsulate the shielding layer 3 on the outer wall of the outer insulating structure 2. Although an additional insulating layer is required and the construction process is more complicated than the following embodiment, the implementation method of disposing of the shielding layer 3 on the outer wall of the outer insulating structure 2 should not be excluded from the scope of protection.
[0035] Preferably, the shielding layer 3 is disposed between the inner insulating structure 1 and the outer insulating structure 2. The distance between the two ends of the inner insulating structure 1 is d, the distance between the two ends of the outer insulating structure 2 is D, and the distance between the two ends of the shielding layer 3 is L, where D = d > L, so that the two ends of the shielding layer 3 do not extend to the outside of the sleeve 100. As one of many embodiments, the inner insulating structure 1 and the outer insulating structure 2 can be integrally formed into the sleeve 100, and the shielding layer 3 is encapsulated between the inner insulating structure 1 and the outer insulating structure 2. When the sleeve 100 is made of epoxy resin, the shielding layer 3 and a part of the ground wire can be molded together with the sleeve 100 in one step using a mold, thereby achieving the production of a sleeve 100 with electromagnetic shielding function while ensuring the simplest production process.
[0036] Furthermore, when the shielding layer 3 is disposed between the inner insulating structure 1 and the outer insulating structure 2, in addition to the aforementioned integral molding technology, the inner insulating structure 1 and the outer insulating structure 2 can also be manufactured by sequentially molding them. Compared with integral molding, separate production has greater flexibility and operability because the integrally molded sleeve 100 has a larger volume, and the epoxy resin and the shielding layer 3 have different coefficients of thermal expansion. Furthermore, the heat changes during the molding of the sleeve 100 may cause inconsistent shrinkage between the two, potentially generating continuous mechanical stress internally and affecting the service life of the sleeve 100.
[0037] Therefore, using a split-type process, the inner insulating structure 1 or the outer insulating structure 2 is first processed, then the shielding layer 3 is embedded, and finally the shielding layer 3 is encapsulated by an insulating layer. The encapsulated insulating layer is then directly used as the outer insulating structure 2 or the inner insulating structure 1. For example:
[0038] When the shielding layer 3 is installed on the inner insulating structure 1, the inner insulating structure 1 is first prepared using a mold, and a first groove is set on the outer wall of the inner insulating structure 1. After the inner insulating structure 1 is formed and inspected for defects such as bubbles, the shielding layer 3 is placed in the first groove. Then, the shielding layer 3 is encapsulated, and the resulting insulating layer is the outer insulating structure 2. This connects the inner wall of the outer insulating structure 2 with the outer wall of the inner insulating structure 1, and encapsulates the shielding layer 3 in the first groove. Figure 4 As shown.
[0039] When the shielding layer 3 is installed on the outer insulating structure 2, the outer insulating structure 2 is first prepared using a mold, and a second groove is provided on the inner wall of the outer insulating structure 2. After the outer insulating structure 2 is formed and inspected for defects such as bubbles, the shielding layer 3 is placed in the second groove. Then, the shielding layer 3 is encapsulated, and the resulting insulating layer is the inner insulating structure 1. This connects the inner wall of the outer insulating structure 2 with the outer wall of the inner insulating structure 1, and encapsulates the shielding layer 3 in the second groove. Figure 6 As shown.
[0040] Through the above structural design, different manufacturing methods can be selected according to the different shapes, materials, and connection methods of the shielding layer 3, for example:
[0041] When the shielding layer 3 is made of a material with good plasticity, it will not spring back and deform after being installed in the first groove. In this case, the shielding layer 3 can be installed on the outer wall of the inner insulation structure 1. This implementation method can greatly increase the versatility of the inner insulation structure 1, and the inner insulation structure 1 can be mass-produced. Then, the outer insulation structure 2 can be prepared according to different sleeve 100 specifications.
[0042] When the shielding layer 3 is made of a material with good elasticity, if the implementation method of installing it on the outer wall of the inner insulating structure 1 is still adopted, the shielding layer 3 will spring back and deform after being installed in the first groove, making it difficult to fix. In order to ensure the normal installation of the shielding layer 3, the implementation method of installing the shielding layer 3 on the inner wall of the outer insulating structure 2 is usually adopted. Although this implementation method is not as universal as the aforementioned implementation method, for the shielding layer 3 that will spring back and deform, no fixing tools are required when installing it in the second groove. After bending the shielding layer 3 and placing it in the second groove, the shielding layer 3 can be well embedded in the second groove under the action of the rebound force. Furthermore, since it is not necessary to prepare the convex ring on the outer wall of the outer insulating structure 2, the influence of the difference in thermal expansion coefficients can be greatly reduced during the molding process of the inner insulating structure 1. At the same time, the molding time of the inner insulating structure 1 is also shorter than that of the outer insulating structure 2.
[0043] Furthermore, the shielding layer 3 is a first shielding layer 4, which is a mesh structure made of conductive material, such as... Figure 3 As shown, the first shielding layer 4 is usually made of copper. During production, the first shielding layer 4 is bent into a cylindrical shape and embedded in the first or second groove. The grid structure can provide high compressive and tensile strength when the sleeve 100 is under pressure or tension, and can effectively absorb and attenuate vibration energy when vibration occurs.
[0044] Furthermore, to achieve a better shielding effect, a foil layer, typically aluminum foil, can be covered on the grid-like first shielding layer 4. The copper grid-like first shielding layer 4 provides mechanical protection and good toughness, and the aluminum foil further enhances the shielding effect.
[0045] Furthermore, the shielding layer 3 is a second shielding layer 5, which is a mesh structure woven from conductive material. Both the warp and weft threads of the second shielding layer 5 are wrapped with a conductive material winding 51, the conductive material of which differs from that of the second shielding layer 5. The diameter of the winding 51 is much smaller than the diameter of the warp and weft threads of the second shielding layer 5. Figure 5 As shown.
[0046] As mentioned in the previous embodiments, the mesh structure can effectively improve compressive strength, tensile strength, and absorb vibration energy. Therefore, in this embodiment, the mesh structure design is still adopted. The difference is that the second shielding layer 5 is woven from conductive material. When the aforementioned mesh structure is embedded in the first or second groove, if the mesh is too small, it is difficult for the epoxy resin to fill the mesh. If the mesh is too large, the shielding effect of the shielding layer 3 will be affected. Furthermore, because it has high compressive strength, it is also difficult to make it completely adhere to the inner surface of the first or second groove. Therefore, in this embodiment, by weaving it into a mesh structure, the shielding layer 3 also has a certain degree of mobility in the radial direction of the sleeve 100. When the second shielding layer 5 is embedded in the first or second groove, when the insulation layer is made, the second shielding layer 5 can adhere to the inner surface of the first or second groove, reducing the probability of unfilled areas or air bubbles. To prevent a decrease in shielding effectiveness due to excessively large mesh sizes, a winding material 51 is wrapped around the warp and weft threads. After weaving the second shielding layer 5, a double shielding layer consisting of the second shielding layer 5 and the winding material 51 is formed. This significantly improves the shielding effect without substantially affecting the volume of the second shielding layer 5. The second shielding layer 5 and the winding material 51 are made of conductive materials with different conductivity, allowing the second shielding layer 5 to withstand electromagnetic waves of various frequencies.
[0047] In the foregoing embodiments, we mentioned that when the shielding layer 3 is made of a material with good plasticity, it can be installed on the outer wall of the inner insulating structure 1. However, this embodiment is quite picky about the material selection of the shielding layer 3. If the shielding layer 3 has good elasticity, it can only be installed on the inner wall of the outer insulating structure 2. Therefore, in this embodiment, we provide an embodiment in which the shielding layer 3 can still be installed on the outer wall of the inner insulating structure 1 when it is made of a material with good elasticity.
[0048] In this embodiment, the shielding layer 3 is a third shielding layer 6, and a fixing ring 61 is provided on the third shielding layer 6. The third shielding layer 6 is fixed in the first groove by the fixing ring 61.
[0049] Furthermore, the fixing ring 61 is made of a heat-shrinkable material, the third shielding layer 6 is composed of several warp threads arranged along the axial direction of the sleeve 100, and the fixing ring 61 is arranged radially along the sleeve 100 to form weft threads. The third shielding layer 6 is woven from warp threads made of conductive material and weft threads formed by the fixing ring 61 to form a cylindrical structure with an inner diameter of R. Figure 7 As shown.
[0050] During installation, the third shielding layer 6 is first fitted over the outer layer of the inner insulating structure 1, positioned at the opening of the first groove. Then, the fixing ring 61 is heated sequentially from top to bottom or bottom to top, causing the inner diameter of the fixing ring 61 to shrink from R to r, where R is the initial inner diameter (as described above), r is the shrunken inner diameter, and r is the diameter of the inner surface of the first groove. Figure 8 As shown, the retaining rings 61 can be tightened onto the inner surface of the first groove. After all the retaining rings 61 are tightened, the excess portion of the third shielding layer 6 is cut off, allowing the third shielding layer 6 to be completely embedded in the first groove. Because a braided structure is also used, the third shielding layer 6 has a certain degree of radial mobility in the sleeve 100, thereby allowing the third shielding layer 6 to completely fit into the first groove and reducing the probability of unfilled areas. At the same time, because the retaining rings 61 need to be tightened sequentially, the warp threads of the third shielding layer 6 can be adjusted at any time, reducing the probability of the warp threads warping or wrinkling in the axial direction of the sleeve 100.
[0051] Although this embodiment has the most complex process, it can simultaneously tighten the fixing ring 61 and adjust the position and tension of the warp threads of the third shielding layer 6, thereby reducing the gaps between the warp threads and increasing the coverage of the third shielding layer 6, resulting in the best shielding effect in this embodiment.
[0052] Furthermore, a foil layer can be placed in the first groove and fixed in the first groove by the third shielding layer 6, thereby greatly improving the shielding performance.
[0053] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.
[0054] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.
[0055] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. Other modifications can be easily made by those skilled in the art. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.
Claims
1. A sleeve with electromagnetic shielding function, comprising: The inner insulating structure (1) and the outer insulating structure (2) are connected to form a sleeve (100). The feature is that it further includes a shielding layer (3), which is disposed on the inner wall of the inner insulating structure (1), and / or on the outer wall of the outer insulating structure (2), and / or between the inner insulating structure (1) and the outer insulating structure (2). When the shielding layer (3) is disposed between the inner insulating structure (1) and the outer insulating structure (2), the distance between the two ends of the inner insulating structure (1) is d, the distance between the two ends of the outer insulating structure (2) is D, and the distance between the two ends of the shielding layer (3) is L, where D=d>L; The outer wall of the inner insulating structure (1) is provided with a first groove, the shielding layer (3) is disposed in the first groove, the inner wall of the outer insulating structure (2) is connected to the outer wall of the inner insulating structure (1), and the shielding layer (3) is encapsulated in the first groove; The inner wall of the outer insulating structure (2) is provided with a second groove, the shielding layer (3) is disposed in the second groove, the inner wall of the outer insulating structure (2) is connected to the outer wall of the inner insulating structure (1), and the shielding layer (3) is encapsulated in the second groove; The inner insulation structure (1) and the outer insulation structure (2) are made of thermosetting resin material; The inner insulation structure (1) and / or the outer insulation structure (2) are formed by direct curing of the thermosetting resin material encapsulating the shielding layer (3).
2. The sleeve with electromagnetic shielding function according to claim 1, characterized in that, The shielding layer (3) is disposed on the inner wall of the inner insulating structure (1), the distance between the two ends of the inner insulating structure (1) is d, and the distance between the two ends of the shielding layer (3) is L, where d > L.
3. The sleeve with electromagnetic shielding function according to claim 1, characterized in that, The shielding layer (3) is disposed on the outer wall of the outer insulating structure (2), the distance between the two ends of the outer insulating structure (2) is D, and the distance between the two ends of the shielding layer (3) is L, where D > L.
4. The sleeve with electromagnetic shielding function according to claim 1, characterized in that, The shielding layer (3) is the first shielding layer (4), which is a mesh structure made of conductive material.
5. The sleeve with electromagnetic shielding function according to claim 1, characterized in that, The shielding layer (3) is a second shielding layer (5). The second shielding layer (5) is a mesh structure woven from conductive material. The warp and weft of the second shielding layer (5) are wrapped with a winding material (51) made of conductive material. The conductive material of the winding material (51) is different from that of the second shielding layer (5).
6. The sleeve with electromagnetic shielding function according to claim 1, characterized in that, The shielding layer (3) is a third shielding layer (6), and a fixing ring (61) is provided on the third shielding layer (6). The third shielding layer (6) is fixed in the first groove by the fixing ring (61).
7. The sleeve with electromagnetic shielding function according to claim 6, characterized in that, The fixing ring (61) is made of a material with heat shrinking function, and the third shielding layer (6) is arranged along the axial direction of the sleeve (100).