Insulating sleeve and cable accessory

Abstract

The invention discloses an insulating sleeve which comprises a conducting rod, an elastic piece, an inner insulating sleeve and an outer insulating sleeve. The conducting rod is sleeved with an elastic piece, a cavity is formed in the elastic piece, an inner insulation sleeve is fixedly connected outside the elastic piece, and an outer insulation sleeve is fixedly connected outside the inner insulation sleeve. The elastic piece with the cavity is arranged between the conducting rod and the inner insulation sleeve, and when the inner insulation sleeve retracts in a vulcanization cooling or low-temperature environment, the elastic piece elastically deforms to fill the retraction space of the inner insulation sleeve, so that the inner insulation sleeve is prevented from being damaged. Therefore, the problems of gaps, degumming and even cracking between the inner insulation sleeve and the conductive rod and between the inner insulation sleeve and the outer insulation sleeve caused by retraction of the inner insulation sleeve are prevented, and the insulation performance of the insulation sleeve is improved.

Description

Technical Field

[0001] This invention relates to the field of components for power equipment, and more particularly to an insulating sleeve. Background Technology

[0002] Currently, most outdoor terminal cable accessories use liquid insulating fillers for internal insulation. However, during installation and use, the product cannot be tilted, limiting its installation and usage conditions. Furthermore, after operation, the sealing ring is in prolonged contact with the high-temperature filler, increasing its aging rate, reducing its sealing performance, and easily leading to poor sealing. Therefore, a method of filling with liquid rubber and then high-temperature vulcanizing it into solid rubber is used for internal insulation of the bushing. After high-temperature vulcanization, the rubber will shrink in volume when cooled to room temperature or in low-temperature operating environments. If the bonding strength between the rubber and the conductive rod / composite bushing (two different materials) is insufficient to resist the resulting shrinkage stress, gaps, delamination, or even cracks may occur between the rubber and the conductive rod / composite bushing, affecting the insulation performance of the insulating bushing. Summary of the Invention

[0003] The purpose of this invention is to provide an insulating sleeve that solves the technical problems of gaps, delamination, and cracking that easily occur between the layers of current insulating sleeves.

[0004] This invention proposes an insulating sleeve in which an elastic element is provided outside the conductive rod, the elastic element having a cavity, an inner insulating sleeve is fixedly connected to the outside of the elastic element, and an outer insulating sleeve is fixedly connected to the outside of the inner insulating sleeve.

[0005] In one embodiment, the elastic element includes a connecting portion and an outer portion extending along the axial direction of the conductive rod. One end face of the connecting portion is fixedly connected to the outer wall surface of the conductive rod, and the other end face is fixedly connected to the inner wall surface of the outer portion. The outer wall surface of the outer portion is fixedly connected to the inner insulating sleeve. The outer portion, the connecting portion, and the conductive rod together form the cavity.

[0006] In one embodiment, the cross-section of the connecting portion along the radial direction of the conductive rod is wavy or sawtooth-shaped.

[0007] In one embodiment, multiple connecting portions are provided, and the multiple connecting portions are arranged around the outer wall surface of the conductive rod. Two adjacent connecting portions, the conductive rod and the outer connecting portion enclose and form the cavity.

[0008] In one embodiment, the cross-sectional area of ​​the cavity in the radial direction of the conductive rod gradually increases along the direction from the conductive rod to the inner insulating sleeve.

[0009] In one embodiment, an inner connection is provided between the connecting part and the conductive rod. The inner connection is located on the bottom wall of the cavity and is coaxially arranged with the outer connection.

[0010] In one embodiment, the elastic element material is semi-conductive rubber; And / or, the inner insulating sleeve material is rubber.

[0011] In one embodiment, the outer insulating sleeve is a composite sleeve, which includes a rigid insulating sleeve and a skirt connected to each other, and the rigid insulating sleeve is connected to the inner insulating sleeve.

[0012] In one embodiment, the inner insulating sleeve is bonded to the outside of the elastic element.

[0013] And / or, the inner insulating sleeve is bonded to the outer insulating sleeve.

[0014] The present invention also provides a cable accessory, including an insulating sleeve and a cover plate as described above, wherein the cover plate is disposed at the openings at both ends of the insulating sleeve.

[0015] The insulating sleeve of this invention includes a conductive rod, an elastic element, an inner insulating sleeve, and an outer insulating sleeve. An elastic element with a cavity is fitted over the conductive rod. The inner insulating sleeve is fixedly connected to the elastic element, and the outer insulating sleeve is fixedly connected to the outer insulating sleeve. This invention, by providing an elastic element with a cavity between the conductive rod and the inner insulating sleeve, allows the elastic element to elastically deform and fill the shrinkage space of the inner insulating sleeve when the inner insulating sleeve shrinks during vulcanization cooling or at low temperatures. This prevents gaps, delamination, or even cracking between the inner insulating sleeve and the conductive rod / outer insulating sleeve due to shrinkage, thereby improving the insulation performance of the insulating sleeve. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of a structure of an embodiment of the insulating sleeve of the present invention; Figure 2 This is another structural schematic diagram of an embodiment of the insulating sleeve of the present invention.

[0018] Explanation of icon numbers: 10. Conductive rod; 20. Elastic element; 20A. Cavity; 21. Connecting part; 22. External part; 23. Internal part; 30. Inner insulating sleeve; 40. Outer insulating sleeve; 41. Rigid insulating sleeve; 42. Umbrella skirt; 100. Insulating sleeve.

[0019] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0021] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0022] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean 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.

[0023] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the word "and / or" throughout the text means including three parallel solutions; taking "A and / or B" as an example, it includes solution A, solution B, or a solution that simultaneously satisfies A and B. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0024] Currently, most outdoor terminal cable accessories use liquid insulating fillers for internal insulation. However, during installation and use, the product cannot be tilted, limiting its installation and usage conditions. Furthermore, after operation, the sealing ring is in prolonged contact with the high-temperature filler, increasing its aging rate, reducing its sealing performance, and easily leading to poor sealing. Therefore, a method of filling with liquid rubber and then high-temperature vulcanizing it into solid rubber is used for internal insulation of the bushing. After high-temperature vulcanization, the rubber will shrink in volume when cooled to room temperature or in low-temperature operating environments. If the bonding strength between the rubber and the conductive rod / composite bushing (two different materials) is insufficient to resist the resulting shrinkage stress, gaps, delamination, or even cracking may occur, affecting the insulation performance of the insulating bushing.

[0025] refer to Figures 1 to 2 The present invention provides an insulating sleeve 100, comprising a conductive rod 10, an elastic element 20, an inner insulating sleeve 30, and an outer insulating sleeve 40. The conductive rod 10 is fitted with an elastic element 20, the elastic element 20 forming a cavity 20A, the inner insulating sleeve 30 is fixedly connected to the outer side of the elastic element 20, and the outer insulating sleeve 40 is fixedly connected to the outer side of the inner insulating sleeve 30.

[0026] Understandably, the conductive rod 10 is cylindrical and can be made of conductive materials such as copper or aluminum. The elastic element 20 can have through holes along the axial direction of the conductive rod 10 to form cavities 20A. The cross-section of the cavity 20A along the radial direction of the conductive rod 10 can be circular, fan-shaped, triangular, etc., and is not limited here. The number of cavities 20A is at least one, but can also be two, three, or even more, and is not limited here. The inner insulating sleeve 30 is crucial for the main insulation, requiring effective electrical insulation and mechanical bonding between the elastic element 20 and the outer insulating sleeve 40. The material of the inner insulating sleeve 30 can be rubber, such as silicone rubber or ethylene propylene rubber. Heat-cured silicone rubber has excellent water repellency and resistance to tracking, and its inherent elasticity can effectively absorb and buffer stress caused by temperature changes; ethylene propylene rubber also has good insulation properties and heat resistance. The outer insulating sleeve 40 is a defense against the external environment and often adopts a composite sleeve structure, balancing mechanical strength and external insulation performance. Therefore, the insulating sleeve 100 forms an internally conductive and externally insulating structure.

[0027] This invention provides an elastic element 20 with a cavity 20A between the conductive rod 10 and the inner insulating sleeve 30. When the inner insulating sleeve 30 shrinks in volume during vulcanization cooling or at low temperature, the elastic element 20 undergoes elastic deformation to fill the shrinkage space of the inner insulating sleeve 30. This prevents gaps, delamination, or even cracking between the inner insulating sleeve 30 and the conductive rod 10 and the outer insulating sleeve 40 due to the shrinkage of the inner insulating sleeve 30, thereby improving the insulation performance of the insulating sleeve 100.

[0028] The present invention provides an embodiment, please refer to it. Figure 1-2The elastic element 20 includes a connecting portion 21 and an outer portion 22 extending axially along the conductive rod 10. One end face of the connecting portion 21 is fixedly connected to the outer wall surface of the conductive rod 10, and the other end face is fixedly connected to the inner wall surface of the outer portion 22. The outer wall surface of the outer portion 22 is fixedly connected to the inner insulating sleeve 30. The outer portion 22, the connecting portion 21, and the conductive rod 10 enclose the cavity 20A.

[0029] Understandably, the elastic element 20 includes a connecting portion 21 and an outer portion 22 extending axially along the conductive rod 10. One end face of the connecting portion 21 is fixedly connected to the outer wall surface of the conductive rod 10, and the other end face is fixedly connected to the inner wall surface of the outer portion 22. The connecting portion 21 and the outer portion 22 can be integrally formed or separately disposed. An inner insulating sleeve 30 is fixedly connected to the outer wall surface of the outer portion 22. The outer portion 22, the connecting portion 21, and the conductive rod 10 enclose the cavity 20A.

[0030] The present invention provides an embodiment, please refer to it. Figure 1-2 The cross-section of the connecting part 21 along the radial direction of the conductive rod 10 is wavy or sawtooth-shaped.

[0031] Understandably, the wavy or sawtooth cross-section of the connecting part 21 in the radial direction of the conductive rod 10 can significantly improve the elastic deformation capacity of the connecting part 21 in the axial and radial directions, and better absorb the stress caused by thermal expansion and contraction.

[0032] The present invention provides an embodiment, please refer to it. Figure 1-2 The connecting part 21 is provided in multiple ways. The multiple connecting parts 21 are arranged around the outer wall surface of the conductive rod 10. Two adjacent connecting parts 21, the conductive rod 10 and the outer connecting part 22 are arranged to form the cavity 20A.

[0033] Understandably, multiple connecting parts 21 are provided, and multiple connecting parts 21 are arranged around the outer wall surface of the conductive rod 10. Two adjacent connecting parts 21, the conductive rod 10 and the outer connecting part 22 enclose a cavity 20A. In this way, multiple independent buffer units are formed. Even if one cavity fails due to extreme conditions, the remaining cavities can still provide elastic deformation and improve reliability.

[0034] The present invention provides an embodiment, please refer to it. Figure 1-2 The cross-sectional area of ​​the cavity 20A in the radial direction of the conductive rod 10 gradually increases along the direction from the conductive rod 10 to the inner insulating sleeve 30.

[0035] Understandably, the cross-sectional area of ​​the cavity 20A in the radial direction of the conductive rod 10 gradually increases along the direction from the conductive rod 10 to the inner insulating sleeve 30. In this way, the cavity 20A forms a gradient buffer space, which makes the stress release more gradual and avoids stress concentration.

[0036] The present invention provides an embodiment, please refer to it. Figure 1-2 An inner connection 23 is provided between the connecting part 21 and the conductive rod 10. The inner connection 23 is located on the bottom wall of the cavity 20A and is coaxially arranged with the outer connection 22.

[0037] Understandably, an inner connection 23 is provided between the connecting part 21 and the conductive rod 10. The inner connection 23 is located on the bottom wall of the cavity 20A and is coaxially arranged with the outer connection 22. The inner connection 23 provides additional radial support for the connecting part 21, which helps to disperse and redistribute the stress concentrated at the root of the connecting part 21, avoids excessive stress concentration, and reduces the risk of fatigue fracture of the connecting part 21.

[0038] Understandably, the elastic element 20 can be made of rubber, or semi-conductive rubber to provide a uniform electric field. The elastic element 20 can be injection molded at high temperature. Using a precision mold, liquid rubber is formed around the conductive rod 10, simultaneously creating the inner connection 23, the connecting part 21, the outer connection 22, and the cavity 20A, which are then firmly bonded to the conductive rod 10. Alternatively, the elastic element 20 can be prefabricated independently and then assembled with the conductive rod 10 and the inner insulating sleeve 30 using an adhesive.

[0039] The present invention provides an embodiment, please refer to it. Figure 1-2 The outer insulating sleeve 40 is a composite sleeve, which includes a rigid insulating sleeve 41 and a skirt 42 connected to each other. The rigid insulating sleeve 41 is connected to the inner insulating sleeve 30.

[0040] Understandably, the rigid insulating bushing 41 serves as the load-bearing and insulating core of the composite bushing, and can be made by combining epoxy resin and glass fiber through a vacuum casting process. Glass fiber provides extremely high mechanical strength, enabling the bushing to withstand enormous bending moments and internal pressures; epoxy resin provides excellent electrical insulation properties. The skirt 42 can be made of silicone rubber, which has excellent hydrophobicity and hydrophobic migration properties. Not only is its surface not easily wetted by water, but even in highly polluted environments, the dirt layer is unlikely to form a continuous conductive film. Furthermore, the skirts 42 are arranged in an alternating pattern of large and small sizes along the axial direction of the conductive rod 10, which improves both the mechanical strength and the anti-creep effect of the skirts 42.

[0041] In one embodiment of the present invention, the inner insulating sleeve 30 is bonded to the outer insulating sleeve 40.

[0042] In one embodiment of the present invention, the elastic element 20 is externally bonded to the inner insulating sleeve 30.

[0043] Understandably, when the inner insulating sleeve 30 is made of rubber, it can be bonded to the elastic element 20 and the outer insulating sleeve 40 by high-temperature injection molding and vulcanization. During the production process, the conductive rod 10 with the elastic element 20 is placed into the outer insulating sleeve 40, and liquid rubber constituting the inner insulating sleeve 30 is injected between the outer insulating sleeve 40 and the conductive rod 10. Through high-temperature vulcanization, the inner insulating sleeve 30 is firmly bonded to the outer connection part 21 of the elastic element 20 and the outer insulating sleeve 40, thereby achieving a seamless connection.

[0044] The present invention also proposes a cable accessory, including an insulating sleeve 100 and a cover plate as described above. The specific structure of the insulating sleeve 100 is as described in the above embodiments. Since this cable accessory adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here. The cover plate is disposed at the openings at both ends of the insulating sleeve 100.

[0045] Understandably, cable accessories may also include flanges, which are located at the openings at both ends of the cable accessory. The flanges and insulating sleeves 100 can be integrally formed during manufacturing, such as by casting or molding, or they can be fixed to the insulating sleeves 100 by welding or high-strength adhesive. The flanges and cover plates are detachably connected.

[0046] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0047] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention without departing from the principles and spirit of the present invention.

Claims

1. An insulating sleeve comprising an electrically conductive rod, characterized in that, The conductive rod is provided with an elastic member, the elastic member is formed with a cavity, the elastic member is fixedly connected with an inner insulating sleeve outside, and the inner insulating sleeve is fixedly connected with an outer insulating sleeve outside.

2. The insulating sleeve of claim 1, wherein, The elastic member comprises a connecting portion and an outer connecting portion which are arranged along the axial direction of the conductive rod, one end surface of the connecting portion is fixedly connected to the outer wall surface of the conductive rod, the other end surface is fixedly connected to the inner wall surface of the outer connecting portion, the outer wall surface of the outer connecting portion is fixedly connected with the inner insulating sleeve, and the outer connecting portion, the connecting portion and the conductive rod enclose the cavity.

3. The insulating sleeve of claim 2, wherein, The cross section of the connecting portion along the radial direction of the conductive rod is in a wave shape or a zigzag shape.

4. The insulating sleeve of claim 2, wherein, The connecting portion is provided with a plurality of connecting portions which are arranged around the outer wall surface of the conductive rod, and the cavity is enclosed by the two adjacent connecting portions, the conductive rod and the outer connecting portion.

5. The insulating sleeve of claim 3, wherein, The cross section of the cavity along the radial direction of the conductive rod gradually increases in the direction from the conductive rod to the inner insulating sleeve.

6. The insulating sleeve of claim 2, wherein, An inner connecting portion is arranged between the connecting portion and the conductive rod, the inner connecting portion is arranged on the bottom wall of the cavity and coaxially arranged with the outer connecting portion.

7. The insulating sleeve of claim 1, wherein, The material of the elastic member is semi-conductive rubber. The material of the inner insulating sleeve is rubber.

8. The insulating sleeve of claim 1, wherein, The outer insulating sleeve is a composite sleeve, the composite sleeve comprises a rigid insulating sleeve and a skirt which are connected with each other, and the rigid insulating sleeve is connected with the inner insulating sleeve.

9. The insulating sleeve of claim 1, wherein, The outer insulating sleeve is bonded to the inner insulating sleeve outside. The elastic member is bonded to the inner insulating sleeve outside.

10. A cable accessory, characterized by The insulating sleeve and the cover plate are provided, the cover plate is arranged at the opening of the two ends of the insulating sleeve.

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