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Title:
INSULATOR AND METHOD OF MANUFACTURING THE SAME
Document Type and Number:
WIPO Patent Application WO/2019/011758
Kind Code:
A1
Abstract:
An insulator and a method of manufacturing the insulator are provided. The insulator includes an insulation tube; and an insulation foam body provided in the insulation tube. A curable adhesive is provided between the insulation foam body and an inner wall of the insulation tube, and the curable adhesive after being cured is softer than both the insulation foam body and the insulation tube.

Inventors:
YANG, Lizhang (Site H Faraday Road, Dorcan, Swindon Wiltshire SN3 5HH, SN3 5HH, GB)
LI, Yugang (C/O: Tyco Electronics Co. Ltd, 287 Qin Jiang Road, Shanghai 3, 200233, CN)
LI, Jian (C/O: Tyco Electronics Co. Ltd, 287 Qin Jiang Road, Shanghai 3, 200233, CN)
Application Number:
EP2018/068166
Publication Date:
January 17, 2019
Filing Date:
July 05, 2018
Export Citation:
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Assignee:
TYCO ELECTRONICS (SHANGHAI) CO. LTD. (Sections F and G Level 1 Building 15, No. 999 Yinglun RoadChina Pilot Free Trade Zone, Shanghai, CN)
TYCO ELECTRONICS UK LTD (Faraday Road, Dorcan, Swindon Wiltshire SN3 5HH, SN3 5HH, GB)
International Classes:
H01B17/32; H01B17/14; H01B19/00
Foreign References:
US4190736A1980-02-26
US20080296045A12008-12-04
GB1253360A1971-11-10
CN202563989U2012-11-28
Other References:
None
Attorney, Agent or Firm:
MURGITROYD & COMPANY (Scotland House, 165-169 Scotland Street, Glasgow Strathclyde G5 8PL, G5 8PL, GB)
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Claims:
What is claimed is,

1. An insulator, comprising:

an insulation tube (120); and

an insulation foam body (140) provided in the insulation tube (120),

wherein a curable adhesive (130) is provided between the insulation foam body (140) and an inner wall of the insulation tube (120), and

wherein the curable adhesive (130) after being cured is softer than both the insulation foam body (140) and the insulation tube (120).

2. The insulator according to claim 1,

wherein the insulation foam body is configured to a columnar insulation foam body (140) which has a length less than or equal to that of the insulation tube (120) and has an outer diameter slightly less than an inner diameter of the insulation tube (120).

3. The insulator according to claim 2,

wherein the columnar insulation foam body (140) is provided in the insulation tube (120), and the curable adhesive (130) is injected into a gap between the columnar insulation foam body (140) and the insulation tube (120).

4. The insulator according to claim 1,

wherein the insulation foam body comprises insulation foam particles (240, 340) which are mixed with the curable adhesive (230, 330) in the insulation tube (240, 340), optionally, each of the insulation foam particles (240, 340) has a spherical shape, a cube shape, a cuboid shape or an ellipsoid shape.

5. The insulator according to claim 1,

wherein the insulation foam body comprises a plurality of columnar insulation foam segments (440, 540), each of which has a length less than that of the insulation tube (420, 520) and has an outer diameter slightly less than an inner diameter of the insulation tube (420, 520).

6. The insulator according to claim 5,

wherein the plurality of columnar insulation foam segments (440, 540) are provided in the insulation tube (420, 520), and the curable adhesive (430, 530) is injected into a gap between the plurality of columnar insulation foam segments (440, 540) and the insulation tube (420, 520).

7. The insulator according to claim 6,

wherein an insulation separation member (550) is provided between each two adjacent columnar insulation foam segments (540). 8. The insulator according to any one of claims 1 to 7,

wherein the insulation foam body (140, 240, 340, 440, 540) is made of polyurethane, polypropylene or polystyrene, preferably, the insulation foam body (140, 240, 340, 440, 540) has a closed cell foaming structure. 9. The insulator according to any one of claims 1 to 7, wherein the curable adhesive

(130, 230, 330, 430, 530) comprises a curable silica gel, and/or the insulation tube (120, 220, 320, 420, 520) comprises a glass fiber epoxy insulation tube.

10. The insulator according to any one of claims 1 to 7, further comprising a silicone rubber umbrella skirt (110, 210, 310, 410, 510) formed on an outer wall of the insulation tube (120, 220, 320, 420, 520).

11. A method of manufacturing an insulator, comprising steps of:

providing an insulation tube (120);

filling the insulation tube (120) with an insulation foam material (140) and a curable adhesive (130); and

curing the curable adhesive (130),

wherein the curable adhesive (130) after being cured is softer than both the insulation foam material (140) and the insulation tube (120).

12. The method according to claim 11, further comprising a step of manufacturing an insulation foam body (140) prior to the step of filling the insulation tube with the insulation foam material and the curable adhesive,

wherein the step of filling the insulation tube with the insulation foam material and the curable adhesive comprises:

filling the insulation tube (120) with the insulation foam body (140); and

injecting the curable adhesive (130) into a gap between the insulation foam body (140) and the insulation tube (120).

13. The method according to claim 11, further comprising a step of manufacturing insulation foam particles (240, 340),

wherein the step of filling the insulation tube with the insulation foam material and the curable adhesive comprises: mixing the insulation foam particles (240, 340) with a liquid curable adhesive (230, 330); and

injecting the insulation foam particles (240, 340) together with the liquid curable adhesive (230, 330) into the insulation tube (220, 320).

14. The method according to claim 11, further comprising a step of manufacturing insulation foam particles (240, 340),

wherein the step of filling the insulation tube with the insulation foam material and the curable adhesive comprises:

injecting a liquid curable adhesive (230, 330) into the insulation tube (220, 320);

filling the insulation tube (220, 320) with the insulation foam particles (240, 340); and mixing the insulation foam particles (240, 340) with the liquid curable adhesive (230,

330). 15. A method of manufacturing an insulator, comprising steps of:

coating an inner wall of an insulation tube (120) with a layer of curable adhesive (130); and

curing the curable adhesive (130); and

filling the insulation tube (120) with an insulation foam material to form an insulation foam body (140) in the insulation tube (120),

wherein the curable adhesive (130) after being cured is softer than both the insulation foam body (140) and the insulation tube (120).

Description:
INSULATOR AND METHOD OF MANUFACTURING THE SAME CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of Chinese Patent Application No. 201710574130.X filed on July 14, 2017 in the State Intellectual Property Office of China, the whole disclosure of which is incorporated herein by reference. BACKGROUND OF THE INVENTION

Field of the Invention

The present disclosure relates to an insulator and a method of manufacturing the insulator.

Description of the Related Art

An insulator for outdoor applications generally includes a porcelain insulator or a composite insulator. The composite insulator is widely used in an electric insulation industry because it has advantages such as light weight, low cost and the like.

SUMMARY OF THE INVENTION

In an aspect, it is provided an insulator including: an insulation tube; and an insulation foam body provided in the insulation tube, wherein a curable adhesive is provided between the insulation foam body and an inner wall of the insulation tube, and the curable adhesive after being cured is softer than both the insulation foam body and the insulation tube.

Optionally, the insulation foam body is configured to a columnar insulation foam body which has a length less than or equal to that of the insulation tube and has an outer diameter slightly less than an inner diameter of the insulation tube.

Optionally, the columnar insulation foam body is provided in the insulation tube, and the curable adhesive is injected into a gap between the columnar insulation foam body and the insulation tube.

Optionally, the insulation foam body includes insulation foam particles which are mixed with the curable adhesive in the insulation tube.

Optionally, each of the insulation foam particles has a spherical shape, a cube shape, a cuboid shape or an ellipsoid shape.

Optionally, the insulation foam body includes a plurality of columnar insulation foam segments, each of which has a length less than that of the insulation tube and has an outer diameter slightly less than an inner diameter of the insulation tube.

Optionally, the plurality of columnar insulation foam segments are provided in the insulation tube, and the curable adhesive is injected into a gap between the plurality of columnar insulation foam segments and the insulation tube.

Optionally, an insulation separation member is provided between each two adjacent columnar insulation foam segments.

Optionally, the insulation foam body is made of polyurethane, polypropylene or polystyrene.

Optionally, the insulation foam body has a closed cell foaming structure.

Optionally, the curable adhesive includes a curable silica gel.

Optionally, the insulation tube includes a glass fiber epoxy insulation tube.

Optionally, the insulator further includes a silicone rubber umbrella skirt formed on an outer wall of the insulation tube.

In another aspect, it is provided a method of manufacturing an insulator, including steps of:

providing an insulation tube;

filling the insulation tube with an insulation foam material and a curable adhesive; and curing the curable adhesive,

wherein the curable adhesive after being cured is softer than both the insulation foam material and the insulation tube.

Optionally, the method may further include a step of manufacturing an insulation foam body prior to the step of filling the insulation tube with the insulation foam material and the curable adhesive,

wherein the step of filling the insulation tube with the insulation foam material and the curable adhesive includes:

filling the insulation tube with the insulation foam body; and

injecting the curable adhesive into a gap between the insulation foam body and the insulation tube.

Optionally, the method may further include a step of manufacturing insulation foam particles,

wherein the step of filling the insulation tube with the insulation foam material and the curable adhesive includes:

mixing the insulation foam particles with a liquid curable adhesive; and

injecting the insulation foam particles together with the liquid curable adhesive into the insulation tube.

Optionally, the method may further include a step of manufacturing insulation foam particles, wherein the step of filling the insulation tube with the insulation foam material and the curable adhesive includes:

injecting a liquid curable adhesive into the insulation tube;

filling the insulation tube with the insulation foam particles; and

mixing the insulation foam particles with the liquid curable adhesive.

In another aspect, it is provided a method of manufacturing an insulator, including steps of:

coating an inner wall of an insulation tube with a layer of curable adhesive; and curing the curable adhesive; and

filling the insulation tube with an insulation foam material to form an insulation foam body in the insulation tube,

wherein the curable adhesive after being cured is softer than both the insulation foam body and the insulation tube. BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features of the present disclosure will become more apparent by describing in detail exemplary embodiments thereof with reference to the accompanying drawings, in which:

FIG. 1 is a schematic cross-sectional view of an insulator according to an embodiment of the present disclosure;

FIG. 2 is a schematic cross- sectional view of an insulator according to another embodiment of the present disclosure;

FIG. 3 is a schematic cross-sectional view of an insulator according to a further embodiment of the present disclosure;

FIG. 4 is a schematic cross-sectional view of an insulator according to a still further embodiment of the present disclosure; and

FIG. 5 is a schematic cross-sectional view of an insulator according to another further embodiment of the present disclosure. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE IVENTION

Exemplary embodiments of the present disclosure will be described hereinafter in detail with reference to the accompanying drawings, wherein like reference numerals refer to like elements. The present disclosure may, however, be embodied in many different forms and should not be construed as being limited to the embodiment set forth herein; rather, these embodiments are provided so that the present disclosure will be thorough and complete, and will fully convey the concept of the disclosure to those skilled in the art.

In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the disclosed embodiments. It will be apparent, however, that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and devices are schematically shown in order to simplify the drawing.

In the related art, a composite insulator generally includes a hollow insulation tube, an insulation rubber umbrella skirt formed on an outer wall of the insulation tube, and an insulation gas or a polyurethane foam material provided in the insulation tube.

The inventors have found that the insulation gas is easy to leak out in a case that the insulator includes the insulation gas provided in the insulation tube. Once the insulation gas leaks out of the insulation tube, it may cause a safety accident. Thereby, it needs to install a monitoring device to monitor the change of the insulation gas inside the insulation tube, so as to detect the leakage of the insulation gas in time.

Further, the inventors have found that, in a case that the insulator includes the polyurethane foam material provided in the insulation tube, the polyurethane foam material is easily peeled off from an inner wall of the insulation tube as shrinkage of the polyurethane foam material is much higher than that of the insulation tube. Thereby, after many cycles of heat expansion and cold contraction, the polyurethane foam material will be peeled off from the inner wall of the insulation tube, resulting in a gap between the polyurethane foam material and the inner wall of the insulation tube. In such a case, external water vapor will easily enter into the insulator through the gap, which may cause the insulator to be easily breakdown by an electric current, and seriously affect the safety performance of the insulator.

According to a general concept of the present disclosure, there is provided an insulator, including: an insulation tube; and an insulation foam body provided in the insulation tube, wherein a curable adhesive is provided between the insulation foam body and an inner wall of the insulation tube, and the curable adhesive after being cured is softer than both the insulation foam body and the insulation tube.

FIG. 1 is a schematic cross-sectional view of an insulator according to an embodiment of the present disclosure. As shown in FIG. 1, the insulator mainly includes a silicone rubber umbrella skirt 110, an insulation tube 120, and an insulation foam body 140. The silicone rubber umbrella skirt 110 is formed on an outer wall of the insulation tube 120. The insulation foam body 140 is provided in the insulation tube 120.

As shown in FIG. 1, in an embodiment, a curable adhesive 130 is provided between the insulation foam body 140 and an inner wall of the insulation tube 120. The curable adhesive 130 after being cured is softer than both the insulation foam body 140 and the insulation tube 120. Thereby, the deformation ability of the curable adhesive 130 after being cured is larger than that of the insulation foam body 140 and the insulation tube 120, so that it may effectively prevent a gap from being generated between the insulation foam body 140 and the inner wall of the insulation tube 120. In this way, the electric insulation performance and the safety performance of the insulator may be improved.

As shown in FIG. 1, in an embodiment, the insulation foam body is configured to a columnar insulation foam body 140 which has a length less than or equal to that of the insulation tube 120 and has an outer diameter slightly less than an inner diameter of the insulation tube 120.

In an embodiment, the columnar insulation foam body 140 may be manufactured in advance and then inserted into the insulation tube 120. After the columnar insulation foam body 140 is inserted into the insulation tube 120, a liquid curable adhesive 130 is injected into a gap between the columnar insulation foam body 140 and the insulation tube 120. Then, the curable adhesive 130 is cured, for example, by heating it to a predetermined temperature or placing it in a room temperature environment for a period of time. After the curable adhesive 130 is cured, the columnar insulation foam body 140 is adhered to the inner wall of the insulation tube 120 by the curable adhesive 130.

In an exemplary embodiment of the present disclosure, the insulation foam body 140 may be made of polyurethane, polypropylene or polystyrene.

In an exemplary embodiment of the present disclosure, the insulation foam body may have a closed cell foaming structure.

In an exemplary embodiment of the present disclosure, the curable adhesive 130 may include a curable silica gel.

In an exemplary embodiment of the present disclosure, the insulation tube 120 may include a glass fiber epoxy insulation tube.

In an exemplary embodiment of the present disclosure, there is provided a method of manufacturing the insulator shown in FIG. 1. The method may include steps of:

manufacturing an insulation foam body 140;

filling an insulation tube 120 with the insulation foam body 140;

injecting a curable adhesive 130 into a gap between the insulation foam body 140 and the insulation tube 120; and

curing the curable adhesive 130.

In another exemplary embodiment of the present disclosure, there is provided a method of manufacturing the insulator shown in FIG. 1. The method may include steps of:

coating an inner wall of an insulation tube 120 with a layer of curable adhesive 130; curing the curable adhesive 130; and

filling the insulation tube 120 with an insulation foam material to form an insulation foam body 140 in the insulation tube 120.

FIG. 2 is a schematic cross- sectional view of an insulator according to another embodiment of the present disclosure. As shown in FIG. 2, the insulator mainly includes a silicone rubber umbrella skirt 210, an insulation tube 220, and an insulation foam body. The silicone rubber umbrella skirt 210 is formed on an outer wall of the insulation tube 220. The insulation foam body is provided in the insulation tube 220.

As shown in FIG. 2, in an embodiment, a curable adhesive 230 is provided between the insulation foam body and an inner wall of the insulation tube 220. The curable adhesive 230 after being cured is softer than both the insulation foam body and the insulation tube 220. Thereby, the deformation ability of the curable adhesive 230 after being cured is larger than that of the insulation foam body and the insulation tube 220, so that it may effectively prevent a gap from being generated between the insulation foam body and the inner wall of the insulation tube 220. In this way, the electric insulation performance and the safety performance of the insulator may be improved.

As shown in FIG. 2, in an embodiment, the insulation foam body includes insulation foam particles 240. The insulation foam particles 240 may be mixed with the curable adhesive 230 and injected into the insulation tube 220 together with the curable adhesive 230. Then, the curable adhesive 230 is cured, for example, by heating it to a predetermined temperature or placing it in a room temperature environment for a period of time. After the curable adhesive 230 is cured, the insulation foam particles 240 are adhered to the inner wall of the insulation tube 220 by the curable adhesive 230.

In another exemplary embodiment of the present disclosure, as shown in FIG. 2, the insulation foam body includes insulation foam particles 240. The insulation foam particles 240 are filled into the insulation tube 220, then the curable adhesive 230 is injected into the insulation tube 220 and mixed with the insulation foam particles 240. Thereafter, the curable adhesive 230 is cured, for example, by heating it to a predetermined temperature or placing it in a room temperature environment for a period of time. After the curable adhesive 230 is cured, the insulation foam particles 240 are adhered to the inner wall of the insulation tube 220 by the curable adhesive 230.

As shown in FIG. 2, in an embodiment, each of the insulation foam particles 240 has a spherical shape. However, the present disclosure is not limited to this. The insulation foam particles 240 may have a cube shape, a cuboid shape, or an ellipsoid shape.

In an exemplary embodiment of the present disclosure, the insulation foam body may be made of polyurethane, polypropylene or polystyrene.

In an exemplary embodiment of the present disclosure, the insulation foam body may have a closed cell foaming structure.

In an exemplary embodiment of the present disclosure, the curable adhesive 230 may include a curable silica gel.

In an exemplary embodiment of the present disclosure, the insulation tube 220 may include a glass fiber epoxy insulation tube.

In an exemplary embodiment of the present disclosure, there is provided a method of manufacturing the insulator shown in FIG. 2. The method may include steps of: manufacturing insulation foam particles 240;

mixing the insulation foam particles 240 with a liquid curable adhesive 230;

injecting the insulation foam particles 240 together with the liquid curable adhesive 230 into an insulation tube 220; and

curing the curable adhesive 230.

In another exemplary embodiment of the present disclosure, there is provided another method of manufacturing the insulator shown in FIG. 2. The method may include steps of: manufacturing insulation foam particles 240;

injecting a liquid curable adhesive 230 into an insulation tube 220;

filling the insulation tube 220 with the insulation foam particles 240, and mixing the insulation foam particles 240 with the liquid curable adhesive 230; and

curing the curable adhesive 230.

FIG. 3 is a schematic cross-sectional view of an insulator according to a further embodiment of the present disclosure. As shown in FIG. 3, the insulator mainly includes a silicone rubber umbrella skirt 310, an insulation tube 320, and an insulation foam body. The silicone rubber umbrella skirt 310 is formed on an outer wall of the insulation tube 320. The insulation foam body is provided in the insulation tube 320.

As shown in FIG. 3, in an embodiment, a curable adhesive 330 is provided between the insulation foam body and an inner wall of the insulation tube 320. The curable adhesive 330 after being cured is softer than both the insulation foam body and the insulation tube 320. Thereby, the deformation ability of the curable adhesive 330 after being cured is larger than that of the insulation foam body and the insulation tube 320, so that it may effectively prevent a gap from being generated between the insulation foam body and the inner wall of the insulation tube 320. In this way, the electric insulation performance and the safety performance of the insulator may be improved.

As shown in FIG. 3, in an embodiment, the insulation foam body includes insulation foam particles 340. The insulation foam particles 340 may be mixed with the curable adhesive 330 and injected into the insulation tube 320 together with the curable adhesive 330. Then, the curable adhesive 330 is cured, for example, by heating it to a predetermined temperature or placing it in a room temperature environment for a period of time. After the curable adhesive 330 is cured, the insulation foam particles 340 are adhered to the inner wall of the insulation tube 320 by the curable adhesive 330.

As shown in FIG. 3, in an embodiment, each of the insulation foam particles 340 has a cube shape. However, the present disclosure is not limited to this. Each of the insulation foam particles 340 may have a spherical shape, a cuboid shape, or an ellipsoid shape.

In an exemplary embodiment of the present disclosure, the insulation foam body may be made of polyurethane, polypropylene or polystyrene.

In an exemplary embodiment of the present disclosure, the insulation foam body may have a closed cell foaming structure.

In an exemplary embodiment of the present disclosure, the curable adhesive 330 may include a curable silica gel.

In an exemplary embodiment of the present disclosure, the insulation tube 320 may include a glass fiber epoxy insulation tube.

In an exemplary embodiment of the present disclosure, there is provided a method of manufacturing the insulator shown in FIG. 3. The method may include steps of:

manufacturing insulation foam particles 340;

mixing the insulation foam particles 340 with a liquid curable adhesive 330;

injecting the insulation foam particles 340 together with the liquid curable adhesive

330 into an insulation tube 320; and

curing the curable adhesive 330.

In another exemplary embodiment of the present disclosure, there is provided another method of manufacturing the insulator shown in FIG. 3. The method may include steps of: manufacturing insulation foam particles 340;

injecting a liquid curable adhesive 330 into an insulation tube 320;

filling the insulation tube 320 with the insulation foam particles 340, and mixing the insulation foam particles 340 with the liquid curable adhesive 330; and

curing the curable adhesive 330.

FIG. 4 is a schematic cross-sectional view of an insulator according to a still further embodiment of the present disclosure. As shown in FIG. 4, the insulator mainly includes a silicone rubber umbrella skirt 410, an insulation tube 420, and an insulation foam body. The silicone rubber umbrella skirt 410 is formed on an outer wall of the insulation tube 420. The insulation foam body is provided in the insulation tube 420.

As shown in FIG. 4, in an embodiment, a curable adhesive 430 is provided between the insulation foam body and an inner wall of the insulation tube 420. The curable adhesive 430 after being cured is softer than both the insulation foam body and the insulation tube 420. Thereby, the deformation ability of the curable adhesive 430 after being cured is larger than that of the insulation foam 440 and the insulation tube 420, so that it may effectively prevent a gap from being generated between the insulation foam body and the inner wall of the insulation tube 420. In this way, the electric insulation performance and the safety performance of the insulator may be improved.

As shown in FIG. 4, in an embodiment, the insulation foam body includes a plurality of columnar insulation foam segments 440. Each of the columnar insulation foam segments 440 has a length less than that of the insulation tube 420 and an outer diameter slightly less than an inner diameter of the insulation tube 420.

Each of the columnar insulation foam segments 440 may be manufactured in advance and then filled into the insulation tube 420. After the columnar insulation foam segments 440 are provided in the insulation tube 420, a liquid curable adhesive 430 is injected into a gap between the columnar insulation foam segments 440 and the insulation tube 420. Then, the curable adhesive 430 is cured, for example, by heating it to a predetermined temperature or placing it in a room temperature environment for a period of time. After the curable adhesive 430 is cured, the columnar insulation foam segments 440 are adhered to the inner wall of the insulation tube 420 by the curable adhesive 430.

In an exemplary embodiment of the present disclosure, the insulation foam body may be made of polyurethane, polypropylene or polystyrene.

In an exemplary embodiment of the present disclosure, the insulation foam body may have a closed cell foaming structure.

In an exemplary embodiment of the present disclosure, the curable adhesive 430 may include a curable silica gel.

In an exemplary embodiment of the present disclosure, the insulation tube 420 may include a glass fiber epoxy insulation tube.

In an exemplary embodiment of the present disclosure, there is provided a method of manufacturing the insulator shown in FIG. 4. The method may include steps of:

manufacturing a plurality of columnar insulation foam segments 440;

filling an insulation tube 420 with the plurality of columnar insulation foam segments

440;

injecting a liquid curable adhesive 430 into a gap between the columnar insulation foam segments 440 and the insulation tube 420; and

curing the curable adhesive 430.

FIG. 5 is a schematic cross-sectional view of an insulator according to another further embodiment of the present disclosure. The insulator shown in FIG. 5 is different from the insulator shown in FIG. 4 mainly in that an insulation separation member 550 is provided between each two adjacent columnar insulation foam segments 540.

As shown in FIG. 5, since each two adjacent columnar insulation foam segments 440 are separated by the insulation separation member 550, each columnar insulation foam segment 540 may be individually adhered to the inner wall of the insulation tube 520 by the curable adhesive 530. In this way, it may reduce difficulty to manufacture the insulator.

Except for the above descriptions, the insulator shown in FIG. 5 is substantially same as the insulator shown in FIG. 4, and further descriptions about the insulator of FIG. 5 are omitted herein.

As used herein, an element recited in the singular and proceeded with the word "a" or "an" should be understood as not excluding plural of said elements or steps, unless such exclusion is explicitly stated. Furthermore, references to "one embodiment" of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Moreover, unless explicitly stated to the contrary, embodiments "including", "comprising" or "having" an element or a plurality of elements having a particular property may include additional such elements not having that property.

It should be appreciated for those skilled in this art that the above embodiments are intended to be illustrated, and not restrictive. For example, many modifications may be made to the above embodiments by those skilled in this art, and various features described in different embodiments may be freely combined with each other without conflicting in configuration or principle.

Although several exemplary embodiments have been shown and described, it would be appreciated by those skilled in the art that various changes or modifications may be made in these embodiments without departing from the principles and spirit of the disclosure, the scope of which is defined in the claims and their equivalents.