Transformer

Abstract

The present invention discloses a mutual inductor, which comprises a power-taking mechanism, wherein the power-taking mechanism comprises a puncture needle with a sharp tip, wherein the puncture needle is configured to puncture the insulating layer of a cable to be tested; the power-taking mechanism further comprises a sealing pad, wherein the sealing pad is arranged between the puncture needle and the cable to be tested; during use, the puncture needle first passes through the sealing pad and then punctures the insulating layer of the cable to be tested, thereby achieving electrical connection between the puncture needle and the conductor of the cable to be tested. In the power-taking puncture structure designed by the present invention, the conductor part of the puncture needle is no longer exposed, thereby avoiding hidden dangers of electricity use and eliminating the risk of electric shock during puncture operations.

Description

Technical Field

[0001] The present invention relates to the field of electric power technology, and in particular to a mutual inductor. Background Art

[0002] The mutual inductor in the prior art generally includes two pivotally connected bodies, namely the first body and the second body, wherein the first body and the second body are respectively provided with an iron core. When the first body and the second body are buckled, the outer shells of the first body and the second body enclose a circular storage cavity, and the cable is clamped in the circular storage cavity so as to test the cable. The voltage signal is obtained from the cable to be tested. For cables with an insulating layer, the traditional method is to strip the insulating layer to obtain electricity. This method of obtaining electricity is not only complicated and inefficient, but also exposes the live parts to the air, seriously affecting the safety of electricity use, and even posing the risk of electric shock during operation. Summary of the invention

[0003] In view of the above-mentioned technical problems existing in the prior art, the present invention provides a mutual inductor, which includes a power supply mechanism, wherein the power supply mechanism includes a puncture needle with a pointed end, and the puncture needle is configured to puncture the insulating layer of the cable to be tested; the power supply mechanism also includes a sealing gasket, which is arranged between the puncture needle and the cable to be tested; during use, the puncture needle first passes through the sealing gasket and then punctures the insulating layer of the cable to be tested, thereby achieving electrical connection between the puncture needle and the conductor of the cable to be tested.

[0004] Furthermore, the power collection mechanism also includes a wiring piece sleeved on the puncture needle and configured to connect the power collection wire. The wiring piece is used to connect the puncture needle and the power collection wire, so that the voltage of the cable punctured by the puncture needle is transmitted to the power collection wire through the puncture needle and the wiring piece.

[0005] Furthermore, the power-taking mechanism also includes a puncture insulation pad configured to insulate the puncture needle from the outside, and the puncture insulation pad is located at the outer end of the puncture needle; during use, external force is applied to the puncture insulation pad and pushes the puncture insulation pad in the direction of the cable to be tested, and the puncture insulation pad pushes the puncture needle so that the puncture needle moves toward the cable to be tested and passes through the sealing pad and the cable insulation layer.

[0006] Preferably, the puncture needle is made of a conductive material, such as a metal material, including but not limited to copper, steel, etc.

[0007] Furthermore, the mutual inductor includes a first body and a second body. When the first body is buckled with the second body, the outer shells of the first body and the second body form a storage cavity. The cable to be tested can be clamped in the storage cavity, and the sealing gasket is arranged on the inner wall of the storage cavity.

[0008] Furthermore, the power taking mechanism further includes a piercing bolt, the first body or the second body has a screw hole matched with the piercing bolt, the piercing bolt is located in the screw hole, the screw portion of the piercing bolt abuts against the piercing insulating pad, and the piercing bolt can be screwed inward to apply a force to the piercing insulating pad in the direction of the cable to be tested. The screw hole can be a threaded hole directly opened on the shell wall of the first body or the second body.

[0009] Furthermore, the power-taking mechanism also includes a puncture bolt and a puncture nut, the tail end of the puncture needle is fixed in the groove on the upper end surface of the puncture insulating pad, the lower end surface of the puncture insulating pad has a groove for accommodating the puncture nut, and the puncture bolt is screwed into the puncture nut; the second shell is provided with a limiting groove for accommodating the puncture insulating pad and the puncture bolt, and a through hole is provided at the bottom of the limiting groove for a tool for screwing the puncture bolt to pass through, and the inner diameter of the through hole is smaller than the outer diameter of the head of the puncture bolt.

[0010] Furthermore, the mutual inductor also includes a cable fastener, which includes connecting arms arranged at two ends and a fastening portion in the middle that is overall arc-shaped, and the connecting arms are connected to the mutual inductor through fastening bolts. By screwing the fastening bolts, the cable fastener can move relative to the first body and the second body along the radial direction of the mutual inductor, thereby achieving adjustment of the inner diameter of the storage cavity.

[0011] Furthermore, the cable fastener has a first arc-shaped recess and a second arc-shaped recess respectively arranged on both sides of the fastening portion, and the diameter of the circle where the first arc-shaped recess is located is less than the diameter of the circle where the second arc-shaped recess is located and the inner diameter of the storage cavity surrounded by the outer shells of the first body and the second body.

[0012] Furthermore, the cable fastener is arranged opposite to the power taking mechanism.

[0013] Furthermore, the first body or the second body has a protrusion protruding outward along the axial direction of the mutual inductor, and the protrusion is configured to load the power extraction mechanism.

[0014] Further, the connecting arm of the cable fastener is connected to the protruding portion by a fastening bolt.

[0015] Further, the first body includes a first iron core, a first shell configured to accommodate the first iron core, and a first cover body configured to close the first shell, and the first cover body is formed with a first arc-shaped groove; the second body includes a second iron core, a second shell configured to accommodate the second iron core, and a second cover body configured to close the second shell, and the second cover body is formed with a second arc-shaped groove; when the first body is buckled with the second body, the first arc-shaped groove and the second arc-shaped groove constitute the storage cavity, wherein the second cover body and the second shell protrude outward along the axial direction of the mutual inductor to form the protrusion.

[0016] Preferably, the protrusion is provided with a screw hole matched with the puncture bolt, and the sealing gasket is fixed to the side of the protrusion facing the receiving cavity.

[0017] More preferably, a groove is provided at the bottom of the arc-shaped groove of the second cover body, the sealing gasket is placed in the groove, and the upper end surface of the sealing gasket protrudes from the groove, and a through hole is provided in the middle of the groove for the puncture needle to pass through; the second shell is provided with a limiting groove for accommodating the puncture insulating pad and the puncture bolt, and a through hole is provided at the bottom of the limiting groove for the puncture bolt to pass through.

[0018] Furthermore, the connecting arm of the cable fastener is connected to the protruding portion of the second cover body by a fastening bolt.

[0019] Preferably, the cable fastener can be moved along the direction of the fastening bolt by screwing the fastening bolt, and the first arc-shaped recess and the second arc-shaped groove can form the first clamping space or the second arc-shaped recess and the second arc-shaped groove can form the second clamping space by disassembling and flipping the cable fastener.

[0020] Furthermore, a first sealing gasket is provided between the first shell and the first cover. Preferably, a sealing sleeve is provided around the first iron core.

[0021] Furthermore, a sealing gasket groove is provided on a side of the second cover body corresponding to the first cover body, and a second sealing gasket is installed in the sealing gasket groove; and a convex ridge matching the sealing gasket groove and the second sealing gasket is provided at a position corresponding to the first cover body.

[0022] Furthermore, the second body of the mutual inductor is cast as a whole using electronic packaging material.

[0023] Furthermore, the second core is provided with a first frame and a second frame butted against each other, and the first frame and the second frame are used for installing windings.

[0024] Furthermore, a spring sheet is arranged between the first iron core and the first shell.

[0025] Furthermore, the first shell is pivotally connected to the second shell.

[0026] Compared with the prior art, the beneficial effects of the mutual inductor of the present invention are as follows: the power-taking puncture structure designed by the present invention, the conductor part of the puncture needle is no longer exposed, avoiding the hidden danger of electricity use and eliminating the risk of electric shock during the puncture operation. In addition, since the cable fastener can form two clamping spaces for clamping cables of different diameters with the second arc groove, thereby increasing the range (or size series) of clamping cables, compared with the mutual inductor in the prior art, it can adapt to more types of cables, and the fixed mutual inductor is more firmly and stably, ensuring the reliability of puncture power taking, and improving the application range of the mutual inductor. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Schematic diagram of the three-dimensional structure of the mutual inductor in the preferred embodiment of the present invention, wherein the cable fasteners and guide posts are removed from the figure.

[0028] Figure 2 It is a schematic diagram of the three-dimensional structure of a mutual inductor in a preferred embodiment of the present invention.

[0029] Figure 3 Schematic diagram of the planar structure of the mutual inductor in a preferred embodiment of the present invention, wherein the second arc-shaped recess is opposite to the second arc-shaped groove.

[0030] Figure 4 Schematic diagram of the planar structure of a mutual inductor in a preferred embodiment of the present invention, wherein the first arc-shaped recess is opposite to the second arc-shaped groove.

[0031] Figure 5 Schematic diagram of the planar structure of the mutual inductor in a preferred embodiment of the present invention, wherein the first shell and the second shell are removed from the figure.

[0032] Figure 6 for Figure 5 A-direction view.

[0033] Figure 7 This is a diagram illustrating the dimensions of the cable clamping range.

[0034] Figure 8 Schematic diagram of the structure of a mutual inductor in a preferred embodiment of the present invention.

[0035] In the figure:

[0036] 10-first body; 11-first shell; 12-first iron core; 13-first cover; 14-first sealing pad; 111-first arc groove; 20-second body; 21-second shell; 22-second iron core; 23-second cover; 24-second sealing pad; 211-second arc groove; 30-cable fastener; 31-first arc recess; 311-first clamping space; 32-second arc recess; 321- The second clamping space; 40-puncture needle; 50-puncture sealing pad; 42-puncture insulating pad; 43-puncture bolt; 44-puncture nut; 60-puncture insulating pad; 70-wiring piece; 81-first frame; 82-second frame; 83-winding; 84-winding output wire; 85-puncture power-taking wire; 80-output wire; 90-shrapnel; 101-circular storage cavity; 102-pin shaft; 103-fastening bolt. DETAILED DESCRIPTION

[0037] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0038] A preferred embodiment of the present invention provides a mutual inductor, which includes a power-taking mechanism, which includes a puncture needle with a pointed end, and the puncture needle is configured to puncture the insulating layer of the cable to be tested; the power-taking mechanism also includes a sealing gasket, which is arranged between the puncture needle and the cable to be tested; during use, the puncture needle first passes through the sealing gasket and then punctures the insulating layer of the cable to be tested, thereby achieving electrical connection between the puncture needle and the conductor of the cable to be tested.

[0039] In another preferred embodiment, the mutual inductor includes a first body and a second body; the first body includes a first shell and a first iron core arranged in the first shell; the second body includes a second shell and a second iron core arranged in the second shell, the first body is formed with a first arc-shaped groove, the second body is formed with a second arc-shaped groove, the first body and the second body are buckled to form a circular storage cavity, and also include a cable fastener that can move up and down, the cable fastener has a first arc-shaped recess and a second arc-shaped recess; when the first arc-shaped recess is opposite to the second arc-shaped recess, a first clamping space is formed, and when the second arc-shaped recess is opposite to the second arc-shaped recess, a second clamping space is formed, and the diameter of the circle where the first arc-shaped recess is located is smaller than the diameter of the circle where the second arc-shaped recess is located.

[0040] In another preferred embodiment, the transformer includes a puncture needle for puncturing and extracting electricity and a puncture insulating pad, the puncture insulating pad is arranged in the puncture limit groove and the bottom of the second arc-shaped groove in the second shell, the puncture needle is arranged in the second shell, one end of which is located in the puncture insulating pad, and the tip for puncture penetrates the bottom of the second arc-shaped groove and enters into the puncture sealing pad.

[0041] In another preferred embodiment, the puncture needle located in the second shell is provided with a wiring piece, and the wiring piece is used to connect the puncture needle and the power-collecting wire, so that the voltage of the cable punctured by the puncture needle is transmitted to the power-collecting wire through the puncture needle and the wiring piece.

[0042] In another preferred embodiment, the first arc-shaped recess and the second arc-shaped recess on the arc-shaped cable fastener are respectively formed at the upper part and the lower part of the arc-shaped cable fastener; two fastening bolts are arranged on the second body, and the cable fastener is provided with fastening nuts corresponding to the two fastening bolts respectively, the two fastening bolts are respectively passed through the two fastening nuts, and the cable fastener can be moved along the direction of the fastening bolts by screwing the fastening bolts, and the first arc-shaped recess and the second arc-shaped groove form the first clamping space or the second arc-shaped recess and the second arc-shaped groove form the second clamping space by disassembling and flipping the cable fastener.

[0043] Example 1

[0044] In a preferred embodiment of the present invention, Figures 1 to 8 As shown, an embodiment of the present invention discloses a mutual inductor, including a first body 10 and a second body 20. The first body 10 includes a first shell 11, a first iron core 12 disposed in the first shell 11, and a first cover 13 for closing the first shell 11; the second body 20 includes a second shell 21, a first skeleton 81, a second skeleton 82, a second iron core 22 disposed in the second shell 21, and a second cover 23 for closing the second shell 21; the first cover 13 is formed with a first arc groove 111, and the second cover 23 is formed with a second arc groove 211. The first body 10 and the second body 20 are buckled to form a circular receiving cavity 101, and the circular receiving cavity 101 is used to clamp cables.

[0045] like Figure 2 , 5As shown in Figures 8 and 9, the transformer of the present invention also includes a power supply mechanism, which includes a puncture needle 40, a puncture sealing pad 50, a puncture insulating pad 42, a puncture bolt 43, a puncture nut 44, and a wiring piece 70. The puncture sealing pad 50 is arranged at the bottom of the second arc groove 211, and the bottom of the arc groove of the second cover body 23 is provided with a groove, and the sealing pad 50 is placed in the groove, and the upper end surface of the sealing pad 50 protrudes from the groove, and a through hole for the puncture needle 40 to pass through is provided in the middle of the groove; the head of the puncture needle 40 penetrates the bottom of the second arc groove 211 and extends into the puncture sealing pad 50. In this embodiment, the head of the puncture needle 40 passes through the through hole at the bottom of the arc groove of the second cover body 23 and extends into the puncture sealing pad 50. In this embodiment, the second cover body 23 and the second shell 21 protrude outward along the axial direction of the transformer to form the protrusion, which is configured to load the power supply mechanism. The tail end of the puncture needle 40 is fixed in the groove on the upper end surface of the puncture insulating pad 42. The lower end surface of the puncture insulating pad 42 has a groove for accommodating the puncture nut 44. The puncture nut 44 is embedded in the groove, and the puncture bolt 43 is screwed into the puncture nut 44. The second shell 21 is provided with a limiting groove for accommodating the puncture insulating pad 42 and the puncture bolt 43, so that the power-taking mechanism is fixed to the second body 20. A through hole is provided at the bottom of the limiting groove for a tool for screwing the puncture bolt 43. The inner diameter of the through hole is smaller than the outer diameter of the head of the puncture bolt 43. The second shell 21 may also include a rubber plug for plugging the through hole. The top surface of the head of the bolt 43 may be provided with a straight or cross groove, or a polygonal countersunk hole, so as to facilitate the tool to screw the bolt 43. In this embodiment, the puncture insulation pad 42 is a hexahedral column. In other embodiments, the puncture insulation pad 42 can be other polyhedral columnar structures. Correspondingly, the limiting groove provided in the second housing 21 is a shape that matches the puncture insulation pad 42. In this way, after the cable is fastened to the first clamping space 311 or the second clamping space 321 by screwing the fastening bolt 103, the puncture bolt 43 is then screwed (along the direction of separation of the puncture bolt 43 and the puncture nut 44). Since the inner diameter of the through hole is smaller than the outer diameter of the head of the puncture bolt 43, the head of the puncture bolt 43 is pushed against the inner edge of the through hole and cannot be withdrawn. Therefore, the puncture nut 44 will push the puncture insulation pad 42 toward the cable, and the puncture insulation pad 42 drives the puncture needle 40 to move toward the cable and compress and penetrate the puncture sealing pad 50 and the cable insulation layer, so that the puncture needle 40 reaches the cable conductor and is in close contact with it, achieving the purpose of puncture and power extraction. Before or after puncture, a rubber plug can be used to plug the through hole to prevent water from entering.

[0046] According to the above, when the cable is clamped, since the puncture sealing pad 50 is appropriately higher than the second arc groove 211 of the second cover body 23, the cable will tightly press the puncture sealing pad 50 and deform it until the cable and the second arc groove 211 of the second cover body 23 are in close contact, thereby ensuring that the puncture position is not exposed and the puncture site is isolated from the outside air, protecting the punctured part of the cable from oxidation and damage, and there is no risk of electric shock during the puncture process.

[0047] In order to electrically connect the puncture needle 40 with the power supply wire 85 so that the puncture needle 40 can obtain electricity, in this embodiment, a wiring piece 70 is sleeved on the puncture needle 40 located in the second shell 21, and the wiring piece 70 is used to connect the power supply wire 85 so that the power supply wire 85 is electrically connected to the puncture needle 40. In this embodiment, the inner hole of the wiring piece 70 needs to be smaller than the outer diameter of the puncture needle 40, so that the wiring piece 70 is in close contact with the puncture needle 40, thereby preventing false connection. The wiring piece 70 is hidden inside the shell, located on the top of the puncture insulation pad 42, and a limit groove can be set on the top of the puncture insulation pad 42, so that it can be well insulated from the outside.

[0048] The mutual inductor of the present invention further comprises a cable fastener 30, which comprises connecting arms (straight arms) arranged at both ends and a fastening portion in the middle which is in an arc shape as a whole, the connecting arms are connected to the mutual inductor by fastening bolts 103, the cable fastener 30 can be moved up and down relative to the first body 10 and the second body 20 by screwing the fastening bolts 103, the fastening portion of the cable fastener 30 has a first arc-shaped recess 31 and a second arc-shaped recess 32; when the first arc-shaped recess 31 is opposite to the second arc-shaped groove 211, a first clamping space 311 is formed, which can clamp thinner cables, such as Figure 4 When the second arc-shaped recess 32 is opposite to the second arc-shaped groove 211, a second clamping space 321 is formed, which can clamp a thicker cable that is not larger than the circular receiving cavity 101, such as Figure 3 As shown; the diameter of the circle where the first arc-shaped recess 31 is located is smaller than the diameter of the circle where the second arc-shaped recess 32 is located.

[0049] like Figure 7 As shown, the width of the connecting arm of the cable fastener 30 is marked as H3, the height from the bottom of the first arc-shaped recess 31 to the upper plane of the cable fastener 30 is marked as H2, the height from the bottom of the second arc-shaped recess 32 to the upper plane of the cable fastener 30 is marked as H1, and the length from the top of the fastening bolt 103 to the upper plane of the cable fastener 30 when the cable fastener is close to the second body is marked as L1, and the diameter of the circular storage cavity is but:

[0050] The first arc-shaped recess 31 and the second arc-shaped groove 211 form a first clamping space 311 to adapt to the cable diameter D:

[0051]

[0052] The second arc-shaped recess 32 and the second arc-shaped groove 211 form a first clamping space 321 to adapt to the cable diameter D:

[0053]

[0054] By setting the appropriate size and combining it with the flip cable fastener, the product can be adapted to almost any size from 0 to The installation of cables with small diameters greatly expands the application range of the transformer.

[0055] In addition, the cable fastener 30 is moved upward by tightening the fastening bolt 103 , so that the first clamping space 311 and the second clamping space 321 can release the clamping of the cable.

[0056] There may be various structures that can realize the up and down movement of the cable fastener 30, and there may be various locations for setting the first arc-shaped recess 31 and the second arc-shaped recess 32. In a preferred embodiment of the present invention, the first arc-shaped recess 31 and the second arc-shaped recess 32 are respectively formed at the upper and lower parts of the cable fastener 30; two fastening bolts 103 are provided on the second shell 21 as guide columns, and guide screw holes corresponding to the two fastening bolts 103 are respectively provided on the connecting arm of the cable fastener 30, and the two fastening bolts 103 are respectively penetrated by two guide screw holes so that the cable fastener 30 can move along the fastening bolts 103.

[0057] According to the above, when it is necessary to clamp a cable with a smaller diameter, the first arc-shaped recess 31 on the cable fastener 30 is aligned with the second arc-shaped groove 211 to form a first clamping space 311, and then the cable fastener 30 is moved down to clamp the cable with a smaller diameter; when it is necessary to clamp a cable with a larger diameter, the cable fastener 30 is first moved up to disengage from the fastening bolt 103, and then the cable fastener 30 is flipped over to make the second arc-shaped recess 32 and the second arc-shaped groove 211 aligned to form a second clamping space 321, and then the cable fastener 30 is moved down to clamp the cable with a larger diameter.

[0058] In a preferred embodiment of the present invention, the second core 22 is provided with a first frame 81 and a second frame 82 butted against each other, the second frame 82 is located below the second core 22, and the combined first frame 81 and second frame 82 are used to install windings.

[0059] In order to make the first core 12 contact with the second core 22 as closely as possible, a spring clip 90 is arranged between the first core 12 and the first body 11. The spring clip 90 can push the first core 12 to the second shell side as much as possible. When the first core and the second core are in close contact, the first core will compress the spring clip, and the elasticity of the spring clip can ensure that the first core and the second core are tightly combined.

[0060] To increase the structural strength, a reinforcing rib is disposed below the second arc groove 211 of the second housing 12 .

[0061] There may be various ways to connect the first shell 11 and the second shell 21 . In a preferred embodiment of the present invention, the first shell 11 and the second shell 21 are pivotally connected via a pin 102 .

[0062] The second body 20 of the mutual inductor of this embodiment is formed by casting the second core 22, the second shell 21, the first frame 81, the second frame 82, the winding 83, the output wire 80, the second cover 23 and the like into one piece using electronic packaging material, and the casting port is the rectangular cavity below the pin 102.

[0063] After the mutual inductor is cast with electronic packaging material, the electronic packaging material combines with other accessories to naturally block the air passage from the inside to the joint surface of the core; on the second cover 23, a sealing gasket groove is provided around the joint surface of the second core 22, and a second sealing gasket 24 is installed in the groove. At the same time, a convex ridge matching the sealing groove and the second sealing gasket 24 is provided at a position corresponding to the first cover 13. After the first body 10 and the second body 20 of the mutual inductor are combined, these three cooperate to isolate the air passage around the joint surface; a sealing sleeve is provided around the first core 12, and a first sealing gasket 14 is provided between the first cover 13 and the first core 12 to block the air passage on the upper part of the joint surface. The combination of these three can achieve the goal of allowing the first core 12 to slide within a certain range and protecting the joint surface of the core, so as to achieve the purpose of waterproofing the product.

[0064] It should be noted that the working principle of the mutual inductor of the present invention is the same as that in the prior art, and the specific functions of the core and other components will not be described in detail herein.

[0065] The above embodiments are only exemplary embodiments of the present invention and are not intended to limit the present invention. The protection scope of the present invention is defined by the claims. Those skilled in the art may make various modifications or equivalent substitutions to the present invention within the essence and protection scope of the present invention, and such modifications or equivalent substitutions shall also be deemed to fall within the protection scope of the present invention.

Claims

1. A mutual inductor, characterized in that: The mutual inductor comprises a power taking mechanism, wherein the power taking mechanism comprises a puncture needle with a sharp tip, wherein the puncture needle is configured to puncture the insulating layer of the cable to be tested; the power taking mechanism further comprises a sealing gasket, wherein the sealing gasket is arranged between the puncture needle and the cable to be tested; During use, the puncture needle first passes through the sealing pad and then pierces the insulating layer of the cable to be tested, thereby achieving electrical connection between the puncture needle and the wire of the cable to be tested; The power taking mechanism also includes a wiring piece sleeved on the puncture needle and configured to connect the power taking wire, the wiring piece is used to connect the puncture needle and the power taking wire, so that the voltage of the cable connected by the puncture needle is transmitted to the power taking wire through the puncture needle and the wiring piece; The power taking mechanism also includes a puncture insulation pad configured to insulate the puncture needle from the outside, and the puncture insulation pad is located at the outer end of the puncture needle; during use, an external force is applied to the puncture insulation pad and pushes the puncture insulation pad in the direction of the cable to be tested, and the puncture insulation pad pushes the puncture needle so that the puncture needle moves toward the cable to be tested and passes through the sealing pad and the cable insulation layer; The mutual inductor comprises a first body and a second body. When the first body is buckled with the second body, the shells of the first body and the second body form a receiving cavity. The cable to be tested can be clamped in the receiving cavity. The sealing gasket is arranged on the inner wall of the receiving cavity. The inner hole of the wiring piece is smaller than the outer diameter of the puncture needle; the wiring piece is hidden inside the shell of the second body and is located on the top of the puncture insulation pad.

2. The mutual inductor according to claim 1, characterized in that: The power extraction mechanism further comprises a piercing bolt, the top end of the screw portion of the piercing bolt abuts against the piercing insulating pad, and force in the direction of the cable to be tested can be applied to the piercing insulating pad by screwing the piercing bolt.

3. The mutual inductor according to claim 1, characterized in that: The mutual inductor also includes a cable fastener, which includes connecting arms arranged at two ends and an arc-shaped fastening portion in the middle. The connecting arms are connected to the mutual inductor through fastening bolts. By screwing the fastening bolts, the cable fastener can move relative to the first body and the second body along the radial direction of the mutual inductor, thereby adjusting the inner diameter of the storage cavity.

4. The mutual inductor according to claim 3, characterized in that: The cable fastener has a first arcuate recess and a second arcuate recess respectively arranged on both sides of the fastening portion, and the diameter of the circle where the first arcuate recess is located is smaller than the diameter of the circle where the second arcuate recess is located and is smaller than the inner diameter of the storage cavity surrounded by the shells of the first body and the second body.

5. The mutual inductor according to claim 3, characterized in that: The cable fastener is arranged opposite to the power taking mechanism.

6. The mutual inductor according to claim 3, characterized in that: The first body or the second body has a protrusion protruding outward along the axial direction of the mutual inductor, and the protrusion is configured to load the power extraction mechanism.

7. The mutual inductor according to claim 6, characterized in that: The connecting arm of the cable fastener is connected to the protruding portion by a fastening bolt.

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