External current transformer

Abstract

The present application discloses an external current transformer, belonging to the technical field of current transformers. It includes a support cylinder, a secondary coil, a protective cylinder, an upper flange, a lower flange, a current guiding member and a sealing assembly; the lower part of the upper flange is welded and fixed to block the upper port of the protective cylinder, the secondary coil is fixed on the support cylinder through a silica gel sleeve, the upper port of the support cylinder is in abutting fit with the lower port of the upper flange through an insulating rubber pad, and the support cylinder is electrically connected to the protective cylinder through the current guiding member; a conical ring is welded and fixed to the lower port of the protective cylinder, the upper part of the lower flange has an abutting ring plate, and the outer edge of the abutting ring plate is provided with a first conical surface; the sealing assembly includes a support ring, a connecting structure and a rubber member, wherein the support ring is located between the first conical surface and the outer conical surface of the conical ring, and the support ring has an upper conical surface and a lower conical surface; the rubber member includes a first conical ring portion, a connecting portion and a second conical ring portion which are connected in sequence from top to bottom. The present application can improve the sealing stability.

Description

Technical Field

[0001] The present application belongs to the technical field of current transformers and relates to an external current transformer. Background Art

[0002] The current transformer for GIS is the protection and measurement unit of GIS. The types of current transformers for GIS are divided into built-in type (the secondary coil is located inside the air chamber) and external type (the secondary coil is located outside the air chamber) according to the position relationship between the secondary coil and the air chamber.

[0003] A Chinese patent application with application number CN2017104643742 discloses an external current transformer for GIS. One end of the protective cover of the external current transformer is sealed and plugged with a transition tube through an annular plug and an annular slot. A sealing ring is installed on the outer wall of the annular plug to achieve waterproof and dustproof properties. At the same time, a waterproof rubber groove is also provided on the outer wall of the annular plug to ensure the waterproof effect.

[0004] However, under the influence of bad weather, harsh environment or high temperature for a long time, the sealing area of ​​the waterproof glue and the sealing ring is small, and the sealing is more likely to fail, which can easily lead to the intrusion of water vapor. Summary of the invention

[0005] Aiming at the problem of poor stability of existing sealing effect, an external current transformer is provided.

[0006] The present application provides an external current transformer, which is implemented by the following technical solutions:

[0007] An external current transformer comprises a support tube, a secondary coil, a protective tube, an upper flange, a lower flange, a flow guide and a sealing assembly; the lower part of the upper flange is welded and fixed and sealed to the upper port of the protective tube, the secondary coil is fixed to the support tube through a silicone sleeve, the upper port of the support tube is abutted and matched with the lower port of the upper flange through an insulating rubber pad, and the support tube is electrically connected to the protective tube through the flow guide; a conical ring is welded and fixed to the lower port of the protective tube, the diameter of the conical ring gradually decreases from top to bottom, the upper part of the lower flange has an abutting ring disk, the outer edge of the abutting ring disk is provided with a first conical surface, and the diameter of the first conical surface gradually increases from top to bottom; the sealing assembly includes The invention comprises a support ring, a connecting structure and a rubber part, wherein the support ring is located between the first conical surface and the outer conical surface of the conical ring, and the support ring has an upper conical surface and a lower conical surface; the rubber part comprises a first conical ring part, a connecting part and a second conical ring part which are connected in sequence from top to bottom, the connecting part is annular, and the cross-sectional shape of the longitudinal section of the connecting part is wavy; the inner conical surface of the second conical ring part fits the first conical surface of the abutting ring disk, the lower conical surface of the support ring fits the outer conical surface of the second conical ring part, the upper conical surface of the support ring fits the outer conical surface of the first conical ring part, and the inner conical surface of the first conical ring part fits the outer conical surface of the conical ring; the connecting structure is used to drive the abutting ring disk to move axially upward and make the abutting ring disk abut against the lower end of the support tube.

[0008] Through the above technical scheme, during installation, the rubber part is first installed on the support ring, and the support ring is placed on the abutting ring disk through the cooperation of the inner cone surface of the second cone ring part and the first cone surface of the abutting ring disk, and then the lower end of the support tube is placed on the abutting ring disk; the abutting ring disk is driven axially upward by the connecting structure, and during this process, the inner cone surface of the first cone ring part gradually fits against the outer cone surface of the second cone ring part, and the inner cone surface of the second cone ring part gradually fits against the first cone surface of the abutting ring disk, until the abutting ring disk is tightly pressed against the lower end of the support tube (the insulating rubber pad is elastically compressed), thereby completing the installation of the overall structure, which is convenient and quick. At the same time, the sealing of the protective tube is completed, and the sealing area is greatly increased by fitting multiple parts of the rubber part, and the double waterproofing achieved by double abutment has stronger sealing stability.

[0009] Furthermore, the conical surface is matched to improve the coaxiality and fitting effect of the abutting ring disk, the supporting ring and the conical ring, thereby further improving the installation accuracy and sealing stability.

[0010] By arranging a conical ring, a supporting ring, a rubber part, an abutting ring disc and a connecting structure, while completing the installation of the overall structure, the conical surface is matched to improve the concentricity and fitting effect of the abutting ring disc, the supporting ring and the conical ring, so as to further improve the installation accuracy and sealing stability, that is, to achieve high installation accuracy, double sealing and waterproofing, and high sealing stability.

[0011] Optionally, the connecting structure includes an internal threaded barrel, an external thread and an annular disk body, the annular disk body is coaxially sleeved on the outer side of the lower flange plate, the inner diameter of the annular disk body is smaller than the outer diameter of the abutting ring plate, the lower port of the internal threaded barrel is coaxially fixedly connected to the annular disk body, the external thread is integrally formed on the outer peripheral surface of the protective barrel, and the internal threaded barrel is threadedly connected to the external thread.

[0012] Through the above technical solution, by tightening the internal threaded sleeve and utilizing the threaded connection, the annular disk body will drive the abutting ring disk to move upward, so that the inner conical surface of the first conical ring part gradually fits the outer conical surface of the second conical ring part, and the inner conical surface of the second conical ring part gradually fits the first conical surface of the abutting ring disk, thereby completing the sealing installation.

[0013] Optionally, the guide member includes a first inclined plate arranged at an angle, an upper end of the first inclined plate having an arc-shaped extension plate extending upward, the outer circumferential surface of the extension plate being fitted to the inner circumferential surface of the protective tube, a lower port of the first inclined plate having an arc-shaped second inclined plate extending downward, the outer circumferential surface of the lower end of the support tube having a second conical surface, and the second conical surface being fitted to the inner circumferential surface of the second inclined plate.

[0014] Through the above technical solution, the first bevel plate is pre-installed in the protective tube through the extension plate, and the abutment ring disk drives the support tube to move upward. During this process, the upper end of the support tube abuts on the insulating rubber pad, and the support tube continues to move upward. The insulating rubber pad is elastically compressed until the second conical surface of the support tube fits with the inner circumferential surface of the second bevel plate, so as to realize the electrical connection between the support tube and the protective tube, which is convenient and quick.

[0015] Optionally, the rubber part is divided into a first layer and a second layer along its own radial direction, a PTFE membrane is provided between the first layer and the second layer, the inner conical surface of the first conical ring portion of the first layer is fitted to the outer conical surface of the conical ring, and the inner conical surface of the second conical ring portion of the first layer is fitted to the first conical surface; the outer conical surface of the first conical ring portion of the second layer is fitted to the upper conical surface of the support ring, and the outer conical surface of the second conical ring portion of the second layer is fitted to the lower conical surface of the support ring; the upper conical surface of the support ring, the lower conical surface of the support ring and the first conical surface are all rough surfaces.

[0016] Through the above technical solution, by providing a layered rubber part and a PTFE membrane and utilizing the low friction coefficient of the PTFE membrane, the first layer and the second layer can be relatively displaced.

[0017] During the process of tightening the internal threaded barrel, the conical ring and the abutting ring disk respectively apply axial force components to the first conical ring portion and the second conical ring portion of the first layer. The axial force components will drive the first conical ring portion and the second conical ring portion of the first layer to make a short axial displacement relative to the second layer. The axial displacement further improves the abutment tightness of the second layer to the first layer, thereby greatly improving the sealing performance of the first layer to the conical ring and the abutting ring disk respectively.

[0018] Optionally, the outer circumferential surface of the support ring is provided with an upper chamfer and a lower chamfer; an axially extending snap-in ring is integrally formed at the inner diameter of the first cone ring portion and the second cone ring portion, and the cone ring and the abutment ring disk are both provided with a snap-in groove for the snap-in ring to be snapped and fixed; a first convex ring is integrally formed on the outer edge of the first cone ring portion, the first convex ring has a third cone surface, and a second convex ring is integrally formed on the outer edge of the second cone ring portion, and the second convex ring has a fourth cone surface; the connecting structure drives the abutment ring disk to move axially upward and the abutment ring disk does not abut the lower end of the support tube, and the upper chamfer and the lower chamfer of the support ring are respectively matched with the third cone surface and the fourth cone surface; in the process of the connecting structure driving the abutment ring disk to move axially upward, the upward movement force of the abutment ring disk is converted into a force forcing the first cone ring portion and the second cone ring portion to elastically stretch along their own generatrix direction through the upper chamfer and the lower chamfer respectively matching with the third cone surface and the fourth cone surface.

[0019] Through the above technical solution, during installation, the rubber part is first pre-fixed on the conical ring and the abutting ring disk through the cooperation of the snap ring and the snap groove, and then the internal threaded tube is tightened. During the upward movement of the abutting ring disk, the upper chamfer and the lower chamfer of the support ring are first cooperated with the third conical surface and the fourth conical surface respectively, while the upper conical surface and the lower conical surface of the support ring are not cooperated with the first conical ring part and the second conical ring part, that is, there is a gap between the upper conical surface and the lower conical surface of the support ring and the first conical ring part and the second conical ring part.

[0020] The abutment ring disk continues to move upward, and the upward movement force of the abutment ring disk is converted into a force forcing the first cone ring portion and the second cone ring portion to elastically stretch along their own generatrix direction through the cooperation of the upper chamfer and the lower chamfer with the third cone surface and the fourth cone surface respectively. This force makes the first cone ring portion pre-flattened and fit on the outer cone surface of the conical ring, and makes the second cone ring portion pre-flattened and fit on the first cone surface of the abutment ring disk.

[0021] The abutting ring disk continues to move upward, and the lower conical surface of the support ring fits against the outer conical surface of the second conical ring portion and forces the second conical ring portion to further press against the first conical surface of the abutting ring disk, and the upper conical surface of the support ring fits against the outer conical surface of the first conical ring portion and forces the first conical ring portion to further press against the outer conical surface of the conical ring, thereby completing the installation and sealing of the overall structure.

[0022] In this way, by cooperating with the third conical surface and the fourth conical surface respectively, the upward movement force of the abutting ring disk is converted into a force forcing the first cone ring portion and the second cone ring portion to elastically stretch along their own generatrix direction, so that the first cone ring portion and the second cone ring portion are pre-flattened to create conditions for subsequent pressing, thereby further improving the fit and sealing between the second cone ring portion and the first cone surface.

[0023] Optionally, both the upper conical surface and the lower conical surface are rough surfaces, the support ring is axially divided into a first sub-ring and a second sub-ring, and the axial gap between the first sub-ring and the second sub-ring is circumferentially arranged as a wide section, a wedge section and a narrow section in sequence; the internal threaded barrel is provided with a vertical groove, a radially sliding sliding plate is provided in the vertical groove, and the sliding plate and the vertical groove are axially slidably matched with each other along the internal threaded barrel, a wedge block is fixed at the end of the sliding plate, and the wedge block is located in the axial gap between the first sub-ring and the second sub-ring.

[0024] Through the above technical solution, in the middle stage of tightening the internal threaded barrel, the sliding vane is radially slid to allow the wedge block to enter the wedge segment (in the later stage of tightening the internal threaded barrel, the wedge block enters the narrow segment), and then the internal threaded barrel continues to be tightened, and the internal threaded barrel drives the sliding vane and the wedge block to rotate circumferentially relative to the support ring, that is, the wedge block moves toward the small end of the wedge segment, and the first sub-ring and the second sub-ring are forced to axially separate and move through the cooperation of the wedge block and the inner wall of the wedge segment, and the axial force of the first sub-ring and the second sub-ring is converted into a force that forces the first cone ring portion and the second cone ring portion to elastically stretch along their own generatrix direction, so that the first cone ring portion and the second cone ring portion can be pre-flattened faster.

[0025] At the same time, the abutting ring disk gradually approaches the conical ring, that is, the first sub-ring and the conical ring approach each other to jointly clamp the first conical ring part, and the second sub-ring and the abutting ring disk approach each other to jointly clamp the second conical ring part, thereby greatly improving the sealing strength.

[0026] The sliding piece is provided to be axially slidingly matched with the vertical groove so that the sliding piece will not be interfered with during the axial movement of the internal threaded barrel.

[0027] Optionally, two connecting plates are fixed to the outer circumferential surface of the internal threaded cylinder, and bolts are vertically penetrated through the connecting plates and the sliding plates.

[0028] Through the above technical solution, the connecting sheet and the sliding sheet are fixed to limit the relative position of the sliding sheet and the internal threaded barrel, thereby limiting the rotatability of the internal threaded barrel and further improving the installation stability.

[0029] Optionally, a water retaining ring is coaxially fixed to the outer peripheral surface of the protective tube, and the lower end surface of the water retaining ring is concave.

[0030] The above technical solution can reduce the occurrence of rainwater flowing down along the outer peripheral surface of the protective tube and entering the internal threaded tube.

[0031] Optionally, the outer circumferential surface of the protective tube is sleeved with a spring, and the protective tube is sleeved with a slip ring, which is axially slidingly connected to the protective tube, and the elastic force of the spring is used to force the slip ring to move downward, and the lower end surface of the slip ring is integrally formed with a plurality of first limit teeth evenly arranged circumferentially, the first limit teeth are in the shape of an isosceles triangle, and the first limit teeth have a first guide surface and a second guide surface; the upper end surface of the internal threaded tube is integrally formed with a plurality of second limit teeth evenly arranged circumferentially, the second limit teeth are in the shape of a right-angled triangle, the second limit teeth have a third guide surface, and the first limit teeth and the second limit teeth are engaged with each other; during the tightening process of the internal threaded tube, the tip of the second limit tooth passes through the first guide surface and the second guide surface of each first limit tooth in turn, and the spring is gradually elastically compressed; when the internal threaded tube is tightened, the tip of the second limit tooth stays in a state of abutting against the second guide surface.

[0032] Through the above technical scheme, during the tightening process of the internal threaded barrel, the second limit tooth gradually approaches the first limit tooth, and in this process, the tip of the second limit tooth passes through the first guide surface and the second guide surface of each first limit tooth in turn, and the spring is gradually elastically compressed; when the tip of the second limit tooth passes through the first guide surface, the third guide surface is in contact with the first guide surface, and the compression degree of the spring is relatively large, and when the tip of the second limit tooth passes through the second guide surface, the spring gradually rebounds; that is, during the tightening process of the internal threaded barrel, the spring is in a process of continuous compression and continuous rebound, and in the overall process, the second limit tooth gradually approaches the first limit tooth, that is, the compression amount of the spring each time gradually increases, and the rebound amount gradually decreases, that is, the elastic potential energy of the spring is in a process of accumulation.

[0033] When the node is finally tightened, the tip of the second limiting tooth stays in abutment with the second guide surface. When the internal threaded tube loosens due to thermal expansion and contraction or vibration, the elastic potential energy of the spring will be converted into a force that forces the internal threaded tube to tighten through the abutment between the tip of the second limiting tooth and the second guide surface, thereby greatly reducing the loosening of the internal threaded tube and improving the sealing performance.

[0034] Optionally, the annular disk body is penetrated by a vertically arranged drainage hole.

[0035] Through the above technical solution, rainwater enters the internal threaded barrel through the upper port of the internal threaded barrel, and the drainage hole can discharge this part of water to reduce water accumulation.

[0036] The beneficial effects of this application are:

[0037] 1. By setting the conical ring, support ring, rubber part, abutment ring disc and connection structure, while completing the installation of the overall structure, the conical surface is matched to improve the concentricity and fitting effect of the abutment ring disc, support ring and conical ring, and further improve the installation accuracy and sealing stability, that is, to achieve high installation accuracy, double sealing and waterproofing, and high sealing stability;

[0038] 2. By respectively cooperating the upper chamfer and the lower chamfer with the third conical surface and the fourth conical surface, the upward movement force of the abutting ring disc is converted into a force for forcing the first conical ring portion and the second conical ring portion to elastically stretch along their generatrix direction, so that the first conical ring portion and the second conical ring portion are pre-flattened to create conditions for subsequent abutment and further improve the sealing performance between the second conical ring portion and the first conical surface;

[0039] 3. By arranging a spring, a first limiting tooth and a second limiting tooth, the elastic potential energy of the spring is gradually accumulated by tightening the internal threaded barrel. When the internal threaded barrel becomes loose due to thermal expansion and contraction or vibration, the elastic potential energy of the spring will be converted into a force forcing the internal threaded barrel to be tightened through the abutment between the tip of the second limiting tooth and the second guide surface, thereby greatly reducing the loosening of the internal threaded barrel and improving the sealing performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a cross-sectional view of the overall structure of Example 1.

[0041] Figure 2 yes Figure 1 A partial enlarged view of point A in the middle.

[0042] Figure 3 It is a partial cross-sectional view of Example 2 for illustrating the matching relationship between the rubber member and the support ring.

[0043] Figure 4 It is a partial cross-sectional view of Example 3 for illustrating the matching relationship between the rubber member and the support ring.

[0044] Figure 5 It is a schematic diagram of Example 3 for reflecting the stretching change process of the rubber member.

[0045] Figure 6 It is a partial cross-sectional view of Example 4 for illustrating the matching relationship between the rubber member and the support ring.

[0046] Figure 7 It is a front view of the internal threaded barrel of Example 4.

[0047] Figure 8 It is a front view of the support ring of Example 4.

[0048] Fig. 9 It is a front view of the internal threaded barrel of Example 5.

[0049] Fig.10 It is a partial cross-sectional view of Example 6 for illustrating the matching relationship between the rubber component and the support ring.

[0050] Fig.11 It is a schematic diagram of Example 6 for illustrating the matching relationship between the first limiting tooth and the second limiting tooth.

[0051] Description of reference numerals: 1. rubber member; 2. support ring; 100. protective tube; 101. conical ring; 102. slide groove; 110. secondary coil; 111. snap ring; 112. snap groove; 113. first convex ring; 114. second convex ring; 115. third conical surface; 116. fourth conical surface; 120. support tube; 121. conical ring body; 122. second conical surface; 130. silicone sleeve; 140. junction box; 150. upper flange; 151. insulating rubber pad; 160. lower flange; 161. abutting ring; 162. first conical surface; 11. first conical ring portion; 12. second conical ring portion; 13. connecting portion; 15. first layer; 16. second layer; 17. P TFE membrane; 21, upper conical surface; 22, lower conical surface; 23, upper chamfer; 24, lower chamfer; 25, first sub-ring; 251, wide section; 252, wedge section; 253, narrow section; 26, second sub-ring; 31, annular disk; 311, drainage hole; 32, internal threaded cylinder; 321, vertical groove; 33, external thread; 34, sliding plate; 341, connecting plate; 342, bolt; 35, wedge block; 51, first oblique plate; 52, extension plate; 53, second oblique plate; 61, slip ring; 611, slider; 62, water retaining ring; 63, spring; 65, first limiting tooth; 651, first guide surface; 652, second guide surface; 66, second limiting tooth; 661, third guide surface. DETAILED DESCRIPTION

[0052] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the attached Figure 1-Figure 11 Shown in.

[0053] In the description of this specification, the description with reference to the terms "certain embodiments", "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0054] Example 1

[0055] Embodiment 1 discloses an external current transformer, such as Figure 1 , Figure 2As shown, the external current transformer includes a support tube 120, a secondary coil 110, a protective tube 100, an upper flange 150, a lower flange 160, a guide piece and a sealing assembly, wherein the upper flange 150 and the lower flange 160 are used for flange connection with the GIS, and the upper flange 150 and the lower flange 160 are correspondingly connected to the protective tube 100 and are coaxially arranged for the corresponding wires to pass through.

[0056] The lower part of the upper flange 150 is welded and fixed to the upper port of the protection tube 100 , and the junction box 140 is welded and fixed to the outer side of the protection tube 100 .

[0057] The secondary coil 110 is fixed to the support tube 120 through a silicone sleeve 130. The support tube 120 is located in the protective tube 100. The upper port of the support tube 120 is abutted with the lower port of the upper flange 150 through an insulating rubber pad 151. Specifically, the upper port of the support tube 120 is integrally formed with a coaxially arranged conical ring body 121. The diameter of the conical ring body 121 gradually increases from top to bottom. An annular insulating rubber pad 151 is bonded and fixed to the lower end of the upper flange 150. The insulating rubber pad 151 is coaxially arranged with the upper flange 150. The insulating rubber pad 151 has an inner conical surface, which is used for the outer conical surface of the conical ring body 121 to fit.

[0058] The support tube 120 is electrically connected to the protective tube 100 through a flow guide. Specifically, the flow guide includes a first inclined piece 51 which is arranged obliquely. The first inclined piece 51 may be copper. An arc-shaped extension piece 52 extends upward from the upper end of the first inclined piece 51. The outer peripheral surface of the extension piece 52 fits the inner peripheral surface of the protective tube 100. At the same time, the extension piece 52 is fixedly connected to the protective tube 100. The fixed connection may be welded or fixed by fasteners. An arc-shaped second inclined piece 53 extends downward from the lower end of the first inclined piece 51. The outer peripheral surface of the lower end of the support tube 120 has a second conical surface 122. The second conical surface 122 fits the inner peripheral surface of the second inclined piece 53, thereby ensuring the flow performance.

[0059] A conical ring 101 is welded and fixed to the lower end of the protective tube 100 . The conical ring 101 is coaxially arranged with the protective tube 100 , and the diameter of the conical ring 101 gradually decreases from top to bottom.

[0060] The upper part of the lower flange 160 has an abutting ring 161 , and the outer edge of the abutting ring 161 is provided with a first conical surface 162 . The diameter of the first conical surface 162 gradually increases from top to bottom, and the taper of the first conical surface 162 is consistent with the taper of the outer conical surface of the conical ring 101 .

[0061] The sealing assembly includes a support ring 2, a connecting structure and a rubber member 1, wherein the support ring 2 is located between the first cone surface 162 and the outer cone surface of the conical ring 101, the support ring 2 is coaxially arranged with the protective tube 100, and the support ring 2 has an upper cone surface 21 and a lower cone surface 22.

[0062] The rubber component 1 includes, from top to bottom, a first conical ring portion 11, a connecting portion 13 and a second conical ring portion 12 which are connected in sequence. The connecting portion 13 is annular and is coaxially arranged with the protective tube 100. The cross-sectional shape of the longitudinal section of the connecting portion 13 is wavy, that is, the connecting portion 13 has the characteristic of being axially compressible and foldable.

[0063] The diameter of the first conical ring portion 11 gradually decreases from top to bottom, and the diameter of the second conical ring portion 12 gradually increases from top to bottom. The inner conical surface of the second conical ring portion 12 fits the first conical surface 162 of the abutting ring disk 161, the lower conical surface 22 of the support ring 2 fits the outer conical surface of the second conical ring portion 12, the upper conical surface 21 of the support ring 2 fits the outer conical surface of the first conical ring portion 11, and the inner conical surface of the first conical ring portion 11 fits the outer conical surface of the conical ring 101.

[0064] The connecting structure is used to drive the abutting ring disk 161 to move axially upward. Specifically, the connecting structure includes an internal threaded tube 32, an external threaded tooth 33 and an annular disk body 31. The annular disk body 31 is made of plastic. The annular disk body 31 is coaxially sleeved on the outer side of the lower flange 160. The inner diameter of the annular disk body 31 is smaller than the outer diameter of the abutting ring disk 161. That is, when installing the annular disk body 31, the annular disk body 31 can be cut into two halves. After the two halves of the annular disk body 31 are assembled into a state of surrounding the lower flange 160, the two halves of the annular disk body 31 are bonded to form a complete annular disk body 31.

[0065] The inner threaded barrel 32 is coaxially arranged with the annular disk body 31 , and the inner diameter of the inner threaded barrel 32 is larger than the outer diameter of the protective barrel 100 . The lower end of the inner threaded barrel 32 is coaxially fixedly connected with the annular disk body 31 , and the fixing method may be bonding or fastener connection.

[0066] The external thread 33 is integrally formed on the outer peripheral surface of the protection tube 100 , and the internal thread of the internal thread tube 32 is threadedly connected to the external thread 33 .

[0067] During installation, first install the rubber part 1 on the support ring 2, place the support ring 2 on the abutment ring disk 161 through the cooperation of the inner conical surface of the second conical ring part 12 and the first conical surface 162 of the abutment ring disk 161, and then place the lower end of the support tube 120 on the abutment ring disk 161.

[0068] By tightening the internal threaded tube 32, the annular disk body 31 abuts against the lower surface of the abutting ring disk 161 to drive the abutting ring disk 161 to move axially upward, and the abutting ring disk 161 also drives the supporting tube 120 to move axially upward. During this process, the inner conical surface of the first conical ring portion 11 gradually fits against the outer conical surface of the second conical ring portion 12, and the inner conical surface of the second conical ring portion 12 gradually fits against the first conical surface 162 of the abutting ring disk 161. At the same time, the outer conical surface of the conical ring body 121 of the supporting tube 120 begins to abut against the inner conical surface of the insulating rubber pad 151.

[0069] Continue to tighten the internal threaded tube 32, the first conical ring portion 11 and the second conical ring portion 12 are compressed, that is, they fit more tightly, and at the same time, the insulating rubber pad 151 is also elastically compressed until the second conical surface 122 of the support tube 120 fits with the inner circumferential surface of the second bevel plate 53 to ensure the flow performance, stop tightening the internal threaded tube 32, and complete the installation of the overall structure.

[0070] In summary, the overall structure is easy and quick to install, and the installation process completes the sealing of the protective tube 100 at the same time. In addition, by fitting the rubber part 1 at multiple locations, the sealing area is greatly increased, and double waterproofing is achieved by double abutment, and the sealing stability is stronger.

[0071] Secondly, the conical surfaces are matched to improve the coaxiality and the fitting effect of the abutting ring disk 161, the support ring 2 and the conical ring 101, so as to further improve the installation accuracy and the sealing stability.

[0072] Furthermore, in order to reduce the intrusion of water vapor caused by the accumulation of rainwater, the following arrangement is also made: the annular disk body 31 is penetrated by a vertically arranged drainage hole 311. When rainwater enters the internal threaded tube 32 through the upper port of the internal threaded tube 32, the drainage hole 311 can discharge this part of the water to reduce water accumulation.

[0073] Example 2

[0074] The difference between Example 2 and Example 1 is that Figure 3 As shown, the rubber component 1 is divided into a first layer 15 and a second layer 16 along its radial direction, that is, the first layer 15 and the second layer 16 are separately arranged, and both the first layer 15 and the second layer 16 are annular structures, the second layer 16 is sleeved on the outside of the first layer 15, and a PTFE membrane 17 is placed between the first layer 15 and the second layer 16. The shapes of the first layer 15 and the second layer 16 are consistent with the rubber component 1, that is, the first layer 15 and the second layer 16 both have a first cone ring portion 11, a connecting portion 13 and a second cone ring portion 12.

[0075] The inner conical surface of the first conical ring portion 11 of the first segment 15 fits the outer conical surface of the conical ring 101 , and the inner conical surface of the second conical ring portion 12 of the first segment 15 fits the first conical surface 162 .

[0076] The outer conical surface of the first conical ring portion 11 of the second layer 16 fits against the upper conical surface 21 of the support ring 2 , and the outer conical surface of the second conical ring portion 12 of the second layer 16 fits against the lower conical surface 22 of the support ring 2 .

[0077] The outer conical surface of the conical ring 101, the upper conical surface 21 of the support ring 2, the lower conical surface 22 of the support ring 2, and the first conical surface 162 are all rough surfaces, thereby increasing the friction force.

[0078] Firstly, by utilizing the low friction coefficient of the PTFE membrane 17, the first layer 15 and the second layer 16 can be relatively displaced. In the process of tightening the internal threaded tube 32, the tapered ring 101 and the abutting ring disk 161 respectively apply axial force components to the first tapered ring portion 11 and the second tapered ring portion 12 of the first layer 15. The axial force components will drive the first tapered ring portion 11 and the second tapered ring portion 12 of the first layer 15 to make a short-distance axial displacement relative to the second layer 16. The axial displacement further improves the abutment tightness of the second layer 16 to the first layer 15, thereby greatly improving the sealing performance of the first layer 15 to the tapered ring 101 and the abutting ring disk 161 respectively.

[0079] Example 3

[0080] The difference between Example 3 and Example 1 is that Figure 4 , Figure 5 As shown ( Figure 5 The solid arrow in the figure indicates the moving direction of the abutting ring disc 161, and the two dotted arrows indicate the elastic stretching directions of the first cone ring portion 11 and the second cone ring portion 12, respectively. The outer peripheral surface of the support ring 2 is provided with an upper chamfer 23 and a lower chamfer 24. The inner diameters of the first cone ring portion 11 and the second cone ring portion 12 are integrally formed with an axially extending snap ring 111, which is coaxially arranged with the rubber member 1, and the conical ring 101 and the abutting ring disc 161 are provided with a snap groove 112 for the snap ring 111 to be snapped and fixed.

[0081] A first convex ring 113 is integrally formed on the outer edge of the first conical ring portion 11 . The first convex ring 113 is coaxially arranged with the first conical ring portion 11 . The first convex ring 113 has a third conical surface 115 , and the diameter of the third conical surface 115 gradually increases from top to bottom.

[0082] A second convex ring 114 is integrally formed on the outer edge of the second conical ring portion 12 . The second convex ring 114 is coaxially arranged with the second conical ring portion 12 . The second convex ring 114 has a fourth conical surface 116 , and the diameter of the fourth conical surface 116 gradually decreases from top to bottom.

[0083] During installation, the rubber component 1 is first pre-fixed on the conical ring 101 and the abutting ring disk 161 by matching the snap ring 111 and the snap groove 112 (in order to improve the matching strength, in other embodiments, a serration structure can be added in the groove wall of the snap groove 112 to further bite the snap ring 111), and then the internal threaded tube 32 is tightened. During the upward movement of the abutting ring disk 161, the lower chamfer 24 and the upper chamfer 23 of the support ring 2 are first matched with the fourth conical surface 116 and the third conical surface 115 respectively, while the upper conical surface 21 and the lower conical surface 22 of the support ring 2 are not matched with the first conical ring portion 11 and the second conical ring portion 12, that is, there is a gap between the upper conical surface 21 and the lower conical surface 22 of the support ring 2 and the first conical ring portion 11 and the second conical ring portion 12.

[0084] The abutting ring disk 161 continues to move upward, and the upward moving force of the abutting ring disk 161 is converted into a force forcing the first cone ring portion 11 and the second cone ring portion 12 to elastically stretch along their own generatrix direction through the cooperation of the upper chamfer 23 and the lower chamfer 24 with the third cone surface 115 and the fourth cone surface 116 respectively. This force makes the first cone ring portion 11 pre-flattened and fit on the outer cone surface of the conical ring 101, and makes the second cone ring portion 12 pre-flattened and fit on the first cone surface 162 of the abutting ring disk 161, so as to create conditions for subsequent pressing.

[0085] The abutting ring disk 161 continues to move upward, and the lower conical surface 22 of the support ring 2 fits against the outer conical surface of the second conical ring portion 12 and forces the second conical ring portion 12 to further press against the first conical surface 162 of the abutting ring disk 161. The upper conical surface 21 of the support ring 2 fits against the outer conical surface of the first conical ring portion 11 and forces the first conical ring portion 11 to further press against the outer conical surface of the conical ring 101, until the second conical surface 122 of the support tube 120 fits against the inner circumferential surface of the second bevel plate 53, thereby completing the installation and sealing of the overall structure.

[0086] Example 4

[0087] The difference between Example 4 and Example 3 is that Figure 6 , Figure 7 , Figure 8 As shown ( Figure 8 The direction of the middle arrow is the moving direction of the wedge block 35 relative to the support ring 2 ), and both the upper conical surface 21 and the lower conical surface 22 are rough surfaces, which increases the friction force and reduces the relative sliding between the support ring 2 and the rubber member 1 .

[0088] The support ring 2 is axially divided into a first sub-ring 25 and a second sub-ring 26, that is, the first sub-ring 25 and the second sub-ring 26 are separately arranged, the upper conical surface 21 and the upper chamfer 23 are located on the first sub-ring 25, the lower conical surface 22 and the lower chamfer 24 are located on the second sub-ring 26, and there is an axial gap between the first sub-ring 25 and the second sub-ring 26, and the axial gap is sequentially arranged along the circumferential direction as a wide section 251, a wedge section 252 and a narrow section 253.

[0089] The internal threaded barrel 32 is penetrated by a vertical groove 321, in which a radially sliding slide 34 is arranged, and the slide 34 and the vertical groove 321 slide together along the axial direction of the internal threaded barrel 32, that is, when the internal threaded barrel 32 rotates, the slide 34 will be driven to rotate, and the internal threaded barrel 32 will not interfere with the slide 34 when it moves axially.

[0090] Furthermore, the number of the sliding vanes 34 is multiple, and the sliding vanes 34 are evenly arranged along the circumference of the internal threaded tube 32 , and the vertical grooves 321 correspond to the sliding vanes 34 one by one.

[0091] A wedge block 35 is fixed to the end of the sliding piece 34 , and the wedge block 35 is located in the axial gap between the first sub-ring 25 and the second sub-ring 26 .

[0092] In the middle of the tightening process of the internal threaded barrel 32, the sliding vane 34 is radially slid to allow the wedge block 35 to enter the wedge segment 252, and then the internal threaded barrel 32 is continuously tightened, and the internal threaded barrel 32 drives the sliding vane 34 and the wedge block 35 to rotate circumferentially relative to the support ring 2, that is, the wedge block 35 moves toward the small end of the wedge segment 252 (the small end of the wedge segment 252 is the narrowest position of the wedge segment 252), and the cooperation between the wedge block 35 and the inner wall of the wedge segment 252 will force the first sub-ring 25 and the second sub-ring 26 to separate and move axially, and the axial force of the first sub-ring 25 and the second sub-ring 26 is converted into a force for forcing the first cone ring portion 11 and the second cone ring portion 12 to elastically stretch along their own generatrix direction, so that the first cone ring portion 11 and the second cone ring portion 12 can be pre-flattened faster. At the same time, the abutting ring disk 161 also gradually approaches the conical ring 101, that is, the first sub-ring 25 and the conical ring 101 approach each other to jointly clamp the first conical ring portion 11, and the second sub-ring 26 and the abutting ring disk 161 approach each other to jointly clamp the second conical ring portion 12, thereby greatly improving the sealing strength.

[0093] At the later stage of the tightening process of the internal threaded tube 32, the wedge block 35 enters the narrow section 253, and the wedge block 35 does not apply an axial force to the first sub-ring 25 and the second sub-ring 26. At this time, only the abutting ring disk 161 applies an axial force to the rubber member 1 to ensure the stability of the fitting and pressing.

[0094] Example 5

[0095] The difference between Example 5 and Example 4 is that Fig. 9 As shown, two connecting pieces 341 are fixed to the outer circumference of the internal threaded tube 32 , and bolts 342 are vertically penetrated through the connecting pieces 341 and the sliding piece 34 .

[0096] When the internal threaded barrel 32 is tightened, the hole on the slide 34 is aligned with the hole on the connecting piece 341, and then the bolt 342 is inserted to fix the connecting piece 341 and the slide 34 to define the relative position of the slide 34 and the internal threaded barrel 32. The slide 34 is limited by the support ring 2 and the slide 34 cannot move axially, thereby limiting the axial position of the internal threaded barrel 32 to limit the rotatability of the internal threaded barrel 32 when it is loose, thereby further improving the installation stability.

[0097] Example 6

[0098] The difference between Example 6 and Example 3 is that Fig.10As shown, a water retaining ring 62 is coaxially fixed to the outer circumference of the protective tube 100 , and the lower end surface of the water retaining ring 62 is concavely arranged, thereby reducing the occurrence of rainwater flowing down along the outer circumference of the protective tube 100 and entering the internal threaded tube 32 .

[0099] And, if Fig.10 , Fig.11 As shown ( Fig.11 The direction of the arrow is the rotation direction of the internal threaded tube 32), the protective tube 100 is sleeved with a slip ring 61, and the slip ring 61 is axially slidingly connected to the protective tube 100. Specifically, an axially arranged slide groove 102 is provided on the outer circumference of the internal threaded tube 32, and a slider 611 is fixed on the inner circumference of the slip ring 61, and the slider 611 is slidingly matched with the slide groove 102.

[0100] A spring 63 is sleeved on the outer circumference of the protective tube 100 , and two ends of the spring 63 abut against the lower surface of the water retaining ring 62 and the upper surface of the slip ring 61 respectively. The elastic force of the spring 63 is used to force the slip ring 61 to move downward.

[0101] The lower end surface of the slip ring 61 is integrally formed with a plurality of first limiting teeth 65 evenly arranged around the circumference. The first limiting teeth 65 are in the shape of an isosceles triangle and have a first guide surface 651 and a second guide surface 652 .

[0102] The upper end surface of the internal threaded tube 32 is integrally formed with a plurality of second limiting teeth 66 evenly arranged circumferentially. The second limiting teeth 66 are in the shape of a right-angled triangle. The second limiting teeth 66 have a third guide surface 661. The first limiting teeth 65 and the second limiting teeth 66 are engaged with each other.

[0103] During the tightening process of the internal threaded barrel 32, the second limiting tooth 66 gradually approaches the first limiting tooth 65, and in this process, the tip of the second limiting tooth 66 passes through the first guide surface 651 and the second guide surface 652 of each first limiting tooth 65 in turn, and the spring 63 is gradually elastically compressed; when the tip of the second limiting tooth 66 passes through the first guide surface 651, the third guide surface 661 fits against the first guide surface 651, and the compression degree of the spring 63 is relatively large, and when the tip of the second limiting tooth 66 passes through the second guide surface 652, the spring 63 gradually rebounds; that is, during the tightening process of the internal threaded barrel 32, the spring 63 is in a process of continuous compression and continuous rebound, and in the overall process, the second limiting tooth 66 gradually approaches the first limiting tooth 65, that is, the compression amount of the spring 63 each time gradually increases, and the rebound amount gradually decreases, that is, the elastic potential energy of the spring 63 is in a process of accumulation.

[0104] When the node is finally tightened, the tip of the second limiting tooth 66 stays in abutment with the second guide surface 652. When the internal threaded tube 32 becomes loose due to thermal expansion and contraction or vibration, the elastic potential energy of the spring 63 will be converted into a force that forces the internal threaded tube 32 to be tightened through the abutment between the tip of the second limiting tooth 66 and the second guide surface 652, thereby greatly reducing the loosening of the internal threaded tube 32 and improving the sealing performance.

[0105] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. External current transformer, characterized in that: The invention comprises a support tube (120), a secondary coil (110), a protective tube (100), an upper flange (150), a lower flange (160), a flow guide and a sealing assembly; the lower part of the upper flange (150) is welded and fixed and sealed to the upper port of the protective tube (100); the secondary coil (110) is fixed to the support tube (120) through a silicone sleeve (130); the upper port of the support tube (120) is abutted against the lower port of the upper flange (150) through an insulating rubber pad (151); the support tube (120) is electrically connected to the protective tube (100) through the flow guide; the protective tube (10 0) is welded and fixed with a conical ring (101) at the lower port, the diameter of the conical ring (101) gradually decreases from top to bottom, the upper part of the lower flange (160) is provided with an abutting ring disk (161), the outer edge of the abutting ring disk (161) is provided with a first conical surface (162), the diameter of the first conical surface (162) gradually increases from top to bottom; the sealing assembly comprises a support ring (2), a connecting structure and a rubber member (1), wherein the support ring (2) is located between the first conical surface (162) and the outer conical surface of the conical ring (101), and the support ring (2) has an upper conical surface (21) and a lower conical surface (22); the rubber member (1) is provided with a support ring (21) and a lower conical surface (22) from top to bottom; The invention comprises a first conical ring portion (11), a connecting portion (13) and a second conical ring portion (12) which are connected in sequence, the connecting portion (13) is annular, and the cross-sectional shape of the longitudinal section of the connecting portion (13) is wavy; the inner conical surface of the second conical ring portion (12) is fitted to the first conical surface (162) of the abutting ring disk (161), the lower conical surface (22) of the support ring (2) is fitted to the outer conical surface of the second conical ring portion (12), the upper conical surface (21) of the support ring (2) is fitted to the outer conical surface of the first conical ring portion (11), and the inner conical surface of the first conical ring portion (11) is fitted to the outer conical surface of the conical ring (101); the connecting structure is used to drive The abutting ring disk (161) moves axially upward and makes the abutting ring disk (161) abut against the lower end of the supporting tube (120); the connecting structure comprises an internal threaded tube (32), an external thread (33) and an annular disk body (31); the annular disk body (31) is coaxially sleeved on the outer side of the lower flange (160); the inner diameter of the annular disk body (31) is smaller than the outer diameter of the abutting ring disk (161); the lower port of the internal threaded tube (32) is coaxially fixedly connected with the annular disk body (31); the external thread (33) is integrally formed on the outer peripheral surface of the protective tube (100); the internal threaded tube (32) and the external thread (33) are threadedly connected.

2. The external current transformer according to claim 1, characterized in that: The guide member comprises a first inclined plate (51) which is arranged obliquely, an arc-shaped extension plate (52) extending upward from the upper end of the first inclined plate (51), an outer peripheral surface of the extension plate (52) being fixedly fitted to the inner peripheral surface of the protective tube (100), an arc-shaped second inclined plate (53) extending downward from the lower end of the first inclined plate (51), and the outer peripheral surface of the lower end of the support tube (120) having a second conical surface (122), the second conical surface (122) being fitted to the inner peripheral surface of the second inclined plate (53).

3. The external current transformer according to claim 1, characterized in that: The rubber component (1) is divided into a first layer (15) and a second layer (16) along its own radial direction; a PTFE film (17) is provided between the first layer (15) and the second layer (16); the inner conical surface of the first conical ring portion (11) of the first layer (15) is bonded to the outer conical surface of the conical ring (101); the inner conical surface of the second conical ring portion (12) of the first layer (15) is bonded to the first conical surface (162); the outer conical surface of the first conical ring portion (11) of the second layer (16) is bonded to the upper conical surface (21) of the support ring (2); the outer conical surface of the second conical ring portion (12) of the second layer (16) is bonded to the lower conical surface (22) of the support ring (2); the upper conical surface (21) of the support ring (2), the lower conical surface (22) of the support ring (2), and the first conical surface (162) are all rough surfaces.

4. The external current transformer according to claim 1, characterized in that: The outer peripheral surface of the support ring (2) is provided with an upper chamfer (23) and a lower chamfer (24); an axially extending snap ring (111) is integrally formed at the inner diameter of the first conical ring portion (11) and the second conical ring portion (12); the conical ring (101) and the abutting ring disk (161) are both provided with a snap groove (112) for the snap ring (111) to be snapped and fixed; a first convex ring (113) is integrally formed at the outer edge of the first conical ring portion (11), and the first convex ring (113) has a third conical surface (115); a second convex ring (114) is integrally formed at the outer edge of the second conical ring portion (12), and the second convex ring (114) has a fourth conical surface (116). 6); when the connecting structure drives the abutting ring disk (161) to move axially upward and the abutting ring disk (161) does not abut against the lower end of the support tube (120), the upper chamfer (23) and the lower chamfer (24) of the support ring (2) respectively cooperate with the third conical surface (115) and the fourth conical surface (116); during the process of the connecting structure driving the abutting ring disk (161) to move axially upward, the upward movement force of the abutting ring disk (161) is converted into a force for forcing the first conical ring portion (11) and the second conical ring portion (12) to elastically stretch along their own generatrix direction through the cooperation of the upper chamfer (23) and the lower chamfer (24) with the third conical surface (115) and the fourth conical surface (116).

5. The external current transformer according to claim 4, characterized in that: The upper conical surface (21) and the lower conical surface (22) are both rough surfaces. The support ring (2) is axially divided into a first sub-ring (25) and a second sub-ring (25). The axial gap between the first sub-ring (25) and the second sub-ring (26) is circumferentially arranged as a wide section (251), a wedge section (252) and a narrow section (253). The internal threaded barrel (32) is provided with a vertical groove (321). A radially sliding sliding plate (34) is arranged in the vertical groove (321). The sliding plate (34) and the vertical groove (321) are axially slidingly matched with each other along the internal threaded barrel (32). A wedge block (35) is fixed at the end of the sliding plate (34). The wedge block (35) is located in the axial gap between the first sub-ring (25) and the second sub-ring (26).

6. The external current transformer according to claim 5, characterized in that: Two connecting plates (341) are fixed to the outer peripheral surface of the internal threaded cylinder (32), and bolts (342) are vertically penetrated through the connecting plates (341) and the sliding plate (34).

7. The external current transformer according to claim 1, characterized in that: A water retaining ring (62) is coaxially fixed to the outer peripheral surface of the protective tube (100), and the lower end surface of the water retaining ring (62) is concavely arranged.

8. The external current transformer according to claim 1, characterized in that: The outer circumferential surface of the protective tube (100) is sleeved with a spring (63), and the protective tube (100) is sleeved with a slip ring (61). The slip ring (61) is axially slidably connected to the protective tube (100). The elastic force of the spring (63) is used to force the slip ring (61) to move downward. The lower end surface of the slip ring (61) is integrally formed with a plurality of first position-limiting teeth (65) evenly arranged around the circumference. The first position-limiting teeth (65) are in the shape of an isosceles triangle. The first position-limiting teeth (65) have a first guide surface (651) and a second guide surface (652). The upper end surface of the internally threaded tube (32) is integrally formed with a plurality of first position-limiting teeth (65) evenly arranged around the circumference. Two limiting teeth (66), the second limiting tooth (66) is in the shape of a right triangle, the second limiting tooth (66) has a third guide surface (661), the first limiting tooth (65) and the second limiting tooth (66) are engaged with each other; during the tightening process of the internal threaded tube (32), the tip of the second limiting tooth (66) passes through the first guide surface (651) and the second guide surface (652) of each first limiting tooth (65) in sequence, and the spring (63) is gradually elastically compressed; when the internal threaded tube (32) is tightened, the tip of the second limiting tooth (66) stays in a state of abutting against the second guide surface (652).

9. The external current transformer according to claim 1, characterized in that: The annular disk body (31) is penetrated by a vertically arranged drainage hole (311).

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