High-voltage conductive slip ring through-wall quick connecting device and assembling and adjusting method thereof
By designing a high-voltage conductive slip ring through wall quick connection device, using T-type plug-and-release head assembly and dual-pass sleeve to achieve rapid plug-and-release and fixing of cables, the problem of low safety and reliability of existing high-voltage slip ring cable installation devices is solved, and the stable transmission of high-voltage cables is achieved and the installation process is simplified.
Patent Information
- Application Number
- CN202411674043.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-21
- Publication Date
- 2025-03-04
AI Technical Summary
The existing high-voltage electric slip ring cable installation devices have low product safety and reliability in the field of high-voltage transmission, and have a large turning radius. Excessive bending during installation can easily lead to damage to the cable and affect power transmission.
A high-voltage conductive slip-over wall quick-connection device is designed, using two sets of T-type plug-and-removal head components and double-pass sleeves. The cable is quickly plug-and-removal and fixed through components such as T-type connectors, copper noses, insulating plugs and stress cones, and sealing and supporting them in combination with wall panels and O-rings.
The wall-through fixing effect of the internal cables and external cables of the high-voltage electric slip ring is achieved, and it has good voltage resistance and sealing and insulation performance, ensuring the stable transmission of the current of the internal and external cables of the high-voltage electric slip ring, simplifying the installation process, and improving safety and reliability.
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Figure CN119560808A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of high-voltage conductive slip ring devices, and in particular to a high-voltage conductive slip ring wall-penetrating quick-connect device and an installation and adjustment method thereof. Background Art
[0002] High-voltage electric slip ring is a key electrical component used to transmit data signals and electric energy in a rotating body. It allows the efficient transmission of power and signals from a fixed part to a rotating part under unlimited continuous rotation. Among them, the cable device is the core component of such high-voltage electric slip rings to withstand high voltage and large current, effectively transmit and distribute electric energy, and ensure the safety and stability of the power system. At present, there are relatively few studies on high-voltage electric slip ring cable installation devices at home and abroad. The product safety and reliability of high-voltage electric slip ring cable installation devices in the field of high-voltage transmission are not high. High-voltage transmission is dangerous, and reliable structural design and insulation material selection are particularly required. In addition, the existing traditional high-voltage electric slip ring cable devices have a large turning radius. Excessive bending during installation can easily cause damage to the cable, affecting power transmission. Therefore, there are disadvantages such as limited installation space and difficult installation.
[0003] Therefore, it is of great significance to design a high-voltage conductive slip ring wall-penetrating quick-connect device. Summary of the invention
[0004] In view of the above technical problems, the technical solution adopted by the present invention is: a high-voltage conductive slip ring wall-penetrating quick-connect device, comprising two groups of T-type plug-in head assemblies and a double-pass sleeve, the two groups of T-type plug-in head assemblies are axially symmetrically arranged at both ends of the double-pass sleeve, and a panel assembly is arranged on the double-pass sleeve, and the panel assembly is arranged between the two groups of T-type plug-in head assemblies to fix and support the two groups of T-type plug-in head assemblies, the T-type plug-in head assembly comprises a copper nose and a T-type joint, the copper nose is arranged inside the T-type joint, and the tail of the copper nose is connected to the bottom of the middle of the T-type joint. The ends of the copper nose are coaxial, the end of the copper nose is coaxial with the double-way casing, the end of the copper nose is threaded with a stud bolt, a nut is threaded on the stud bolt, an insulating plug is threaded on the end of the stud bolt, the insulating plug is arranged at the tail end of the T-joint, the front end of the T-joint is sleeved on one end of the double-way casing, the tail thread of the stud bolt is installed on the end of the double-way casing, the insulating plug cooperates with the stud bolt and nut to install the T-joint at one end of the double-way casing, and the two sets of T-type plug-in head assemblies and the double-way casing can realize quick plugging and unplugging of cables.
[0005] Furthermore, the panel assembly includes a through-wall panel, four groups of hexagonal bolts, the through-wall panel and the double-pass sleeve are coaxial, the through-wall panel is sleeved on the double-pass sleeve, an O-ring is arranged between the through-wall panel and the double-pass sleeve, the four groups of hexagonal bolts are evenly arranged on the outer periphery of the double-pass sleeve, and the hexagonal bolts are threaded to fix the double-pass sleeve on the through-wall panel. The O-ring is installed between the double-pass sleeve and the through-wall panel to achieve a sealing effect, and the through-wall panel facilitates the installation of the integral quick-connect device at the target installation position.
[0006] Furthermore, the panel assembly further includes a second spring washer and a second flat washer, a group of second spring washers corresponds to a group of second flat washers, a group of second flat washers corresponds to a group of hexagonal bolts, the second flat washer is arranged above the double-pass sleeve, the second spring washer is arranged between the hexagonal bolt and the second flat washer, the second spring washer and the second flat washer are coaxial with the hexagonal bolt, and the second spring washer and the second flat washer are sleeved on the hexagonal bolt. The second spring washer and the second flat washer improve the firmness of the installation of the through-wall panel and the double-pass sleeve, and facilitate the installation and removal of the through-wall panel and the double-pass sleeve.
[0007] Furthermore, the T-type plug assembly further includes a first spring washer and a first flat washer, both of which are coaxial with the stud bolt, and are sequentially arranged between the nut and the copper nose. The first spring washer and the first flat washer ensure the stability of the copper nose fixation.
[0008] Furthermore, the inner material of the insulating plug is copper, and the outer material of the insulating plug is insulating material. The insulating plug with copper inner material has good conductivity and can ensure stable current transmission. The insulating material outside the insulating plug prevents accidents such as arc discharge caused by factors such as overvoltage.
[0009] Furthermore, at the contact point between the insulating plug and the tail end of the T-shaped connector, the surface of the insulating plug is coated with silicone grease. The surface of the insulating plug is coated with silicone grease to ensure the insulation of the insulating layer.
[0010] Furthermore, a stress cone is provided at the tail of the copper nose, the stress cone is provided at the bottom of the middle of the T-joint, the stress cone is provided inside the T-joint, the stress cone is coaxial with the tail of the copper nose, and silicone grease is applied inside the stress cone. The stress cone with silicone grease applied inside passes through the insulation layer of the cable core and is fixed to ensure safe and reliable transmission of the current inside the cable.
[0011] Furthermore, the shell of the T-shaped connector is a silicone rubber shell, and a sealing cap is provided at the tail end of the T-shaped connector. The silicone rubber shell of the T-shaped connector ensures good insulation, and the sealing cap can isolate external pollution.
[0012] The present invention also discloses a method for assembling and adjusting a high-voltage conductive slip ring through-wall quick-connect device, which uses the above device and specifically comprises the following steps: Step 1: Use the through-wall panel as a substrate, design a sealing groove on the through-wall panel, and install an O-ring on the sealing groove to achieve a sealing function; Step 2: Install the middle part of the double-pass sleeve on the through-wall panel. Use four evenly spaced hexagonal bolts to connect the double-pass sleeve and the through-wall panel, which ensures firmness and facilitates installation and removal. Step 3: Install a set of T-type plug-in head components first, cut and strip the core of one end of the external output high-voltage cable and clean it in place to ensure the insulation of the insulation layer; pass the stress cone with silicone grease applied inside through the cable core insulation layer and fix it, clean the excess silicone grease on the core to ensure safe and reliable transmission of the current inside the cable; Step 4: Insert the copper nose into the cable core conductor and crimp it tightly, clean the surface of the copper nose and stress cone and apply silicone grease; push the tail of the T-type connector from top to bottom onto the cable with the stress cone and copper nose installed. The T-type connector is a silicone rubber shell with good insulation performance; Step 5: Screw the stud bolt into one end of the double-pass sleeve, align the stud bolt with the copper nose installation hole, put the front end of the T-joint on the double-pass sleeve, and then place the first flat washer, the first spring washer and the nut in sequence and tighten them; Step 6: Insert the insulating plug coated with silicone grease into the tail end of the T-joint and tighten it with stud bolts; the inner core of the insulating plug is made of copper material, and the outer part of the insulating plug is made of insulating material. Install a sealing cap at the tail of the T-joint to isolate it from external pollution; Step 7: Similarly, follow the steps from step 3 to step 6 above to install the internal output high-voltage cable and another set of T-type plug-in head components on the other end of the double-pass bushing.
[0013] The T-type plug-in assembly is the movable end, ensuring that the cable can be quickly plugged in and out; the panel assembly serves as the installation fixed end and plays a fixing and supporting role.
[0014] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention is provided with two groups of T-type plug-in head assemblies, and utilizes a high-voltage T-type double-pass bushing quick-plug structure cable installation method to replace the traditional high-voltage electric slip ring cable installation method, which not only realizes the wall-penetrating fixing effect of the internal cable and the external cable of the high-voltage electric slip ring, realizes a good switching function, and has good pressure resistance, thereby ensuring the stable transmission of the current of the internal and external cables of the high-voltage electric slip ring; (2) The present invention is provided with a T-type joint, which is an integrally formed part, and the shell of the T-type joint is silicone rubber. The T-type joint is sealed between the double-pass bushing and the wall-penetrating panel by an O-type sealing ring, thereby achieving good sealing and insulation performance, not easy to age, and can adapt to the harsh marine environment, has good environmental adaptability, and can meet the use requirements of the high-voltage electric slip ring cable equipment for long-life operation; (3) The present invention has a simple and compact structure, and the installation of the high-voltage cable is simple and quick, which effectively prevents the cable from being placed in a disorderly manner or even entangled and torn off, which not only saves the internal use space of the high-voltage electric slip ring equipment, ensures beauty and reliability, but also can realize the safe and stable transmission of the current inside and outside the high-voltage electric slip ring. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 It is a schematic diagram of the first viewing angle of the overall structure of the present invention.
[0016] Figure 2 It is the front view of the present invention.
[0017] Figure 3 It is a left view of the present invention.
[0018] Figure 4 for Figure 3 Cross-section view along the AA direction.
[0019] Figure 5 for Figure 4 A partial enlarged view of part B.
[0020] Figure 6 for Figure 4 A partial enlarged view of part C.
[0021] Figure numbers: 1-sealing cap; 2-insulating plug; 3-stud bolt; 4-nut; 5-first spring washer; 6-first flat washer; 7-double-way sleeve; 8-O-ring; 9-wall panel; 10-T-joint; 11-stress cone; 12-copper nose; 13-second spring washer; 14-second flat washer; 15-hexagonal bolt. DETAILED DESCRIPTION
[0022] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.
[0023] Example: Figure 1-Figure 6The high-voltage conductive slip ring wall-penetrating quick-connect device shown in the figure comprises two groups of T-type plug-in head assemblies and a double-pass sleeve 7, the two groups of T-type plug-in head assemblies are axially symmetrically arranged at both ends of the double-pass sleeve 7, a panel assembly is arranged on the double-pass sleeve 7, the panel assembly is arranged between the two groups of T-type plug-in head assemblies, fixes and supports the two groups of T-type plug-in head assemblies, the T-type plug-in head assembly comprises a copper nose 12 and a T-type connector 10, the copper nose 12 is arranged inside the T-type connector 10, the tail of the copper nose 12 is coaxial with the bottom of the middle part of the T-type connector 10, and the end of the copper nose 12 is coaxial with the double The through sleeve 7 is coaxial, and the end of the copper nose 12 is threadedly installed with a stud bolt 3, a nut 4 is threadedly installed on the stud bolt 3, and an insulating plug 2 is threadedly installed on the end of the stud bolt 3. The insulating plug 2 is arranged at the tail end of the T-type connector 10, and the front end of the T-type connector 10 is sleeved on one end of the double-way sleeve 7, and the tail end of the stud bolt 3 is threadedly installed on the end of the double-way sleeve 7. The insulating plug 2 cooperates with the stud bolt 3 and the nut 4 to install the T-type connector 10 at one end of the double-way sleeve 7. The two sets of T-type plug-in head assemblies and the double-way sleeve 7 can realize quick plugging and unplugging of cables.
[0024] like Figure 1 , Figure 2 , Figure 4 , Figure 6 As shown, the panel assembly includes an O-ring 8, a through-wall panel 9, a second spring washer 13, a second flat washer 14, and a hexagonal bolt 15. The through-wall panel 9 is coaxial with the double-pass sleeve 7, and the through-wall panel 9 is sleeved on the double-pass sleeve 7. An O-ring 8 is arranged between the through-wall panel 9 and the double-pass sleeve 7. The O-ring 8 is installed between the double-pass sleeve 7 and the through-wall panel 9 to achieve a sealing effect. The through-wall panel 9 facilitates the installation of the overall quick-connect device at the target installation position; four groups of hexagonal bolts 15 are evenly arranged on the outer periphery of the double-pass sleeve 7, one group of second spring washers 13 corresponds to one group of second flat washers 14, and one group of first The two flat washers 14 correspond to a group of hexagonal bolts 15, the second flat washer 14 is arranged above the double-pass sleeve 7, the second spring washer 13 is arranged between the hexagonal bolt 15 and the second flat washer 14, the second spring washer 13 and the second flat washer 14 are coaxial with the hexagonal bolt 15, the second spring washer 13 and the second flat washer 14 are sleeved on the hexagonal bolt 15, the hexagonal bolt 15 fixes the double-pass sleeve 7 on the through-wall panel 9 through a threaded connection, the second spring washer 13 and the second flat washer 14 improve the firmness of the installation of the through-wall panel 9 and the double-pass sleeve 7, and at the same time facilitate the installation and disassembly of the through-wall panel 9 and the double-pass sleeve 7.
[0025] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5As shown, the T-type plug-in head assembly is axially symmetrically arranged on both sides of the double-pass sleeve 7. The T-type plug-in head assembly includes a sealing cap 1, an insulating plug 2, a stud bolt 3, a nut 4, a first spring washer 5, a first flat washer 6, a T-type joint 10, a stress cone 11, and a copper nose 12. The copper nose 12 is arranged inside the T-type joint 10, and the shell of the T-type joint 10 is a silicone rubber shell to ensure good insulation; the tail of the copper nose 12 is coaxial with the bottom of the middle part of the T-type joint 10, and the end of the copper nose 12 is coaxial with the double-pass sleeve 7. One end of the stud bolt 3 is installed on one end of the double-pass sleeve 7 through threaded cooperation, and the end of the copper nose 12 is installed on the stud bolt 3 through threaded cooperation. The stress cone 11 is arranged at the bottom of the middle part of the T-type joint 10, and the stress cone 11 is coaxial with the tail of the copper nose 12. Silicone grease is applied inside the stress cone 11. The stress cone 11 with silicone grease applied inside passes through the cable core insulation layer and is fixed to ensure the safety and reliability of the current inside the cable. transmission; the insulating plug 2 is arranged inside the tail end of the T-shaped connector 10, the inner material of the insulating plug 2 is copper, and the outer material of the insulating plug 2 is an insulating material. The insulating plug 2 with copper as the inner material has good conductivity and can ensure stable current transmission. The insulating material outside the insulating plug 2 prevents accidents such as arc discharge caused by factors such as excessive voltage; the other end of the stud bolt 3 is installed with the insulating plug 2 through a thread, the first spring washer 5 and the first flat washer 6 are coaxial with the stud bolt 3, the nut 4 is arranged between the insulating plug 2 and the copper nose 12, the nut 4 is installed on the stud bolt 3 through a thread, the first spring washer 5 and the first flat washer 6 are arranged on the stud bolt 3 in sequence, the first spring washer 5 and the first flat washer 6 are arranged in sequence between the nut 4 and the copper nose 12, the first spring washer 5 and the first flat washer 6 ensure the stability of the fixation of the copper nose 12 and the stud bolt 3; the sealing cap 1 is covered on the outside of the tail end of the T-shaped connector 10 to protect and isolate pollution.
[0026] A method for assembling and adjusting a high-voltage conductive slip ring through-wall quick-connect device, using the above device, comprises the following steps: Step 1: Use the through-wall panel 9 as a substrate, design a sealing groove on the through-wall panel 9, and install an O-ring 8 on the sealing groove to achieve a sealing function; Step 2: Install the middle part of the double-pass sleeve 7 on the through-wall panel 9. The double-pass sleeve 7 and the through-wall panel 9 are evenly connected with four hexagonal bolts 15 to ensure firmness and facilitate installation and removal; Step 3: First install a set of T-type plug-in head components, cut and strip the wire core at one end of the external output high-voltage cable and clean it in place to ensure the insulation of the insulation layer; pass the stress cone 11 with silicone grease applied inside through the cable core insulation layer and fix it, clean the excess silicone grease on the wire core to ensure safe and reliable transmission of the current inside the cable; Step 4: Insert the copper nose 12 into the cable core conductor and crimp it tightly, clean the surface of the copper nose 12 and the stress cone 11 and apply silicone grease; push the tail of the T-type connector 10 from top to bottom onto the cable with the stress cone 11 and the copper nose 12 installed. The T-type connector 10 is a silicone rubber shell with good insulation performance; Step 5: Screw the stud bolt 3 into one end of the double-pass sleeve 7, align the stud bolt 3 with the installation hole of the copper nose 12, put the front end of the T-type connector 10 on the double-pass sleeve 7, and then place the first flat washer 6, the first spring washer 5 and the nut 4 in sequence and tighten them; Step 6: Insert the insulating plug 2 coated with silicone grease into the tail end of the T-joint 10 and tighten it with the stud bolt 3; the inner core of the insulating plug 2 is made of copper material, and the outer part of the insulating plug is made of insulating material. Install the sealing cap 1 at the tail end of the T-joint 10 to isolate it from external pollution; Step 7: Similarly, according to the above steps from step 3 to step 6, the internal output high-voltage cable and another set of T-type plug-in head components are installed at the other end of the double-pass bushing 7.
[0027] The T-type plug-in assembly is the movable end, ensuring that the cable can be quickly plugged in and out; the panel assembly serves as the installation fixed end and plays a fixing and supporting role.
[0028] The present invention is not limited to the above-mentioned specific implementation modes. Various changes made by technicians in the relevant technical field based on the above-mentioned conception without creative work all fall within the protection scope of the present invention.
Claims
1. A high voltage conductive slip ring wall penetration quick connection device, characterized in that: The invention comprises two groups of T-shaped plug-in head assemblies and a double-pass sleeve (7), wherein the two groups of T-shaped plug-in head assemblies are axially symmetrically arranged at two ends of the double-pass sleeve (7), and a panel assembly is arranged on the double-pass sleeve (7), and the panel assembly is arranged between the two groups of T-shaped plug-in head assemblies to fix and support the two groups of T-shaped plug-in head assemblies, wherein the T-shaped plug-in head assembly comprises a copper nose (12) and a T-shaped joint (10), wherein the copper nose (12) is arranged inside the T-shaped joint (10), the tail of the copper nose (12) is coaxial with the bottom of the middle of the T-shaped joint (10), the end of the copper nose (12) is coaxial with the double-pass sleeve (7), and the end of the copper nose (12) is coaxial with the double-pass sleeve (7), and the end of the copper nose (12) is coaxial with the bottom of the middle of the T-shaped joint (10). A stud bolt (3) is threadedly mounted on the stud bolt (3), a nut (4) is threadedly mounted on the stud bolt (3), an insulating plug (2) is threadedly mounted on the end of the stud bolt (3), the insulating plug (2) is arranged at the rear end of the T-shaped connector (10), the front end of the T-shaped connector (10) is sleeved on one end of a double-pass sleeve (7), the rear end of the stud bolt (3) is threadedly mounted on the end of the double-pass sleeve (7), the insulating plug (2) cooperates with the stud bolt (3) and the nut (4) to mount the T-shaped connector (10) on one end of the double-pass sleeve (7), and the two sets of T-shaped plug-in head assemblies and the double-pass sleeve (7) enable the cable to be quickly plugged in and out.
2. A high voltage conductive slip ring wall penetration quick connection device according to claim 1, characterized in that: The panel assembly comprises a through-wall panel (9), four groups of hexagonal bolts (15), the through-wall panel (9) and the double-pass sleeve (7) being coaxial, the through-wall panel (9) being sleeved on the double-pass sleeve (7), an O-ring (8) being arranged between the through-wall panel (9) and the double-pass sleeve (7), the four groups of hexagonal bolts (15) being evenly arranged on the outer periphery of the double-pass sleeve (7), and the hexagonal bolts (15) being fixedly mounted on the through-wall panel (9) by threaded connection with the double-pass sleeve (7).
3. A high voltage conductive slip ring wall penetration quick connection device according to claim 2, characterized in that: The panel assembly further comprises a second spring washer (13) and a second flat washer (14); a group of second spring washers (13) corresponds to a group of second flat washers (14); a group of second flat washers (14) corresponds to a group of hexagonal head bolts (15); the second flat washer (14) is arranged above the double-pass sleeve (7); the second spring washer (13) is arranged between the hexagonal head bolt (15) and the second flat washer (14); the second spring washer (13), the second flat washer (14) and the hexagonal head bolt (15) are coaxial; and the second spring washer (13) and the second flat washer (14) are sleeved on the hexagonal head bolt (15).
4. A high voltage conductive slip ring wall penetration quick connection device according to claim 1, characterized in that: The T-shaped plug-in head assembly further comprises a first spring washer (5) and a first flat washer (6), the first spring washer (5) and the first flat washer (6) being coaxial with the stud bolt (3), and the first spring washer (5) and the first flat washer (6) being arranged in sequence between the nut (4) and the copper nose (12).
5. A high voltage conductive slip ring wall penetration quick connection device according to claim 1, characterized in that: The inner material of the insulating plug (2) is copper, and the outer material of the insulating plug (2) is insulating material.
6. A high voltage conductive slip ring wall penetration quick connection device according to claim 1, characterized in that: At the point where the insulating plug (2) contacts the tail end of the T-shaped connector (10), silicone grease is applied to the surface of the insulating plug (2).
7. A high voltage conductive slip ring wall penetration quick connection device according to claim 1, characterized in that: The tail of the copper nose (12) is provided with a stress cone (11), the stress cone (11) is arranged at the bottom of the middle of the T-shaped joint (10), the stress cone (11) is arranged inside the T-shaped joint (10), the stress cone (11) is coaxial with the tail of the copper nose (12), and silicone grease is applied inside the stress cone (11).
8. A high voltage conductive slip ring wall penetration quick connection device according to claim 1, characterized in that: The outer shell of the T-shaped connector (10) is a silicone rubber outer shell, and a sealing cap (1) is provided at the tail end of the T-shaped connector (10).
9. A method for assembling and adjusting a high-voltage conductive slip ring through-wall quick-connect device, using the device described in claims 1-8, characterized in that: Step 1: Using the through-wall panel (9) as a substrate, designing a sealing groove on the through-wall panel (9), and installing an O-ring (8) on the sealing groove to achieve a sealing function; Step 2: Install the middle part of the double-pass sleeve (7) on the through-wall panel (9), and use four evenly spaced hexagonal bolts (15) between the double-pass sleeve (7) and the through-wall panel (9), so as to facilitate installation and removal while ensuring firmness; Step 3: First install a set of T-type plug-in head components, cut and strip the wire core at one end of the external output high-voltage cable and clean it in place to ensure the insulation of the insulation layer; pass the stress cone (11) with silicone grease applied inside through the cable core insulation layer and fix it, clean the excess silicone grease on the wire core, and ensure safe and reliable transmission of current inside the cable; Step 4: Insert the copper nose (12) into the cable core conductor and crimp it tightly, clean the surface of the copper nose (12) and the stress cone (11) and apply silicone grease; push the tail of the T-type connector (10) from top to bottom into the cable with the stress cone (11) and the copper nose (12) installed. The T-type connector (10) is a silicone rubber shell with good insulation performance; Step 5: Screw the stud bolt (3) into one end of the double-pass sleeve (7), align the stud bolt (3) with the installation hole of the copper nose (12), put the front end of the T-type connector (10) on the double-pass sleeve (7), and then place the first flat washer (6), the first spring washer (5) and the nut (4) in sequence and tighten them; Step 6: Insert the insulating plug (2) coated with silicone grease into the tail end of the T-shaped connector (10) and tighten it with the stud bolt (3); the inner core of the insulating plug (2) is made of copper material, and the outer part of the insulating plug is made of insulating material. Install a sealing cap (1) at the tail end of the T-shaped connector (10) to isolate it from external pollution; Step 7: Similarly, according to the above steps 3 to 6, install the internal output high-voltage cable and another set of T-type plug-in head components on the other end of the double-pass sleeve (7).