Fire-resistant, low-smoke, halogen-free power cable for rail transit and preparation process thereof

Abstract

This invention discloses a fire-resistant, flame-retardant, low-smoke, halogen-free power cable for rail transit and its manufacturing process, relating to the field of power cable technology. It aims to solve the technical problem of cable outer sheaths being easily damaged by rodents. The invention includes a cable body with multiple anti-biting blocks arranged on its circumferential outer wall. The cable body also includes conductor cores, an insulation layer, a flame-retardant layer, an inner sheath, an armor layer, and an outer sheath. Multiple anti-biting blocks form a group, and each group is arranged in a circular array on the circumferential outer wall of the outer sheath. Multiple groups of anti-biting blocks are arranged linearly. The sidewalls of the anti-biting blocks have an outwardly convex arc surface structure, and the inner cavity of the anti-biting block is filled with multiple spherical crystals. This invention has the advantage of preventing rodents from directly biting the outer sheath, thus encouraging them to voluntarily refrain from biting.

Description

Technical Field

[0001] This invention relates to the field of power cable technology, and more specifically, to a fire-resistant, flame-retardant, low-smoke, halogen-free power cable for rail transit and its manufacturing process. Background Technology

[0002] Fire-resistant, flame-retardant, low-smoke, halogen-free power cables for rail transit are special safety cables designed specifically for rail transit systems such as subways, light rail, and high-speed rail. They possess flame-retardant, fire-resistant, low-smoke, and halogen-free properties in fire conditions. They can maintain power supply for extended periods even under high-temperature flames, ensuring the normal operation of critical systems such as emergency power supply, fire protection, and lighting. They are key supporting cables for rail transit power supply systems.

[0003] Cable outer sheaths are typically made of low-smoke halogen-free flame-retardant polyolefin material. This material is an environmentally friendly polymer composite material that does not contain halogen elements such as fluorine, chlorine, bromine, and iodine. It produces extremely low smoke during combustion and releases no toxic or corrosive gases, possessing properties such as environmental friendliness, halogen-free nature, low smoke, flame retardancy, weather resistance, and oil resistance. However, in the complex environments of rail transit such as subways, tunnels, and underground utility tunnels, this material has low hardness and weak tear resistance, making it susceptible to damage from rodents. Over long-term use, rodents can easily chew through or gnaw through the outer sheath, leading to moisture ingress, grounding faults, and in severe cases, affecting power supply safety. Therefore, we propose a fire-resistant, flame-retardant, low-smoke halogen-free power cable for rail transit and its manufacturing process. Summary of the Invention

[0004] The purpose of this invention is to provide a fire-resistant, flame-retardant, low-smoke, halogen-free power cable for rail transit and its manufacturing process, in order to solve the technical problem that the outer sheath of the cable is easily damaged by rodents.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a fire-resistant, flame-retardant, low-smoke, halogen-free power cable for rail transit, comprising a cable body, wherein multiple anti-bite blocks are arranged on the outer circumference of the cable body; the cable body further comprises a conductor core, the conductor core is wrapped with an insulation layer, the insulation layer is wrapped with a flame-retardant layer, the flame-retardant layer is wrapped with an inner sheath, the inner sheath is wrapped with an armor layer, and the armor layer is wrapped with an outer sheath; multiple anti-bite blocks form a group, each group of anti-bite blocks is arranged in a ring array on the outer circumference of the outer sheath, and multiple groups of anti-bite blocks are arranged in a linear manner; the sidewall of the anti-bite block has an outwardly convex arc surface structure, and the inner cavity of the anti-bite block is filled with multiple spherical crystals, the spherical crystals being granular spherical structures made of glass.

[0006] A manufacturing process for a power cable, comprising the following steps:

[0007] S1. Conductor core preparation: Multiple copper wires are twisted together at a specified pitch to form the conductor core using a stranding process.

[0008] S2. Insulation layer coating operation: The prepared conductor core is fed into the extruder, and the insulating material is uniformly extruded and coated on the outside of the conductor core under high temperature and high pressure to form an insulation layer.

[0009] S3. Flame-retardant layer coating operation: The wire core with the insulation layer is fed into the coating equipment. The flame-retardant material is evenly coated on the outside of the insulation layer using the wrapping process to form a flame-retardant layer.

[0010] S4. Inner sheath covering operation: After the flame retardant layer is cooled and shaped, it is fed into the extruder to uniformly extrude the polyvinyl chloride material to cover the outside of the flame retardant layer, forming the inner sheath.

[0011] S5. Armor layer covering operation: The wire core covered with the inner sheath is sent into the armoring equipment. The steel strip is evenly wrapped around the outside of the inner sheath according to the specified density and pitch using the wrapping process to form the armor layer.

[0012] S6. Outer sheath covering operation: After the armor layer is processed, it is fed into the extruder to uniformly extrude and cover the outside of the armor layer with polyvinyl chloride material to form an outer sheath.

[0013] S7. Finished product inspection and winding operation: Inspect the prepared cables and remove unqualified products.

[0014] S8. Injection molding operation of the bite block: Molten plastic containing glass particles is injected into the cavity that is attached to the side wall of the outer sheath through the molding machine. After cooling and molding, the bite block is formed and connected to the side wall of the outer sheath.

[0015] Preferably, the molding machine includes a mold assembly, an injection molding assembly, and a guiding assembly; the mold assembly includes a fixed frame, a drive assembly is arranged on one side of the fixed frame, and an upper mold assembly and a lower mold assembly are arranged inside the fixed frame; the drive assembly includes an upper drive gear and a lower drive gear rotatably arranged on the inner sidewall of the fixed frame, and the upper drive gear and the lower drive gear are capable of synchronously rotating in opposite directions; the upper mold assembly includes an upper horizontal moving frame slidably arranged in the horizontal direction on the inner sidewall of the fixed frame, and an upper vertical moving frame slidably arranged in the vertical direction inside the upper horizontal moving frame, the bottom of the upper vertical moving frame being connected to the upper mold through an upper rectangular plate; the sidewall of the upper vertical moving frame is provided with an annular groove, and the annular groove has a quasi-rectangular groove structure. The annular groove is provided with teeth, and the upper drive gear meshes with the teeth. When the upper drive gear rotates, it drives the upper vertical moving frame to move the upper mold first in the horizontal direction and then in the vertical direction, forming a rectangular path motion state. The lower mold assembly includes a lower horizontal moving frame, a lower vertical moving frame, a lower rectangular plate, and a lower mold arranged symmetrically with the upper mold assembly. When the lower drive gear rotates, the lower mold of the lower mold assembly can also perform a rectangular path motion state. When the upper drive gear and the lower drive gear rotate synchronously in opposite directions, the upper mold and the lower mold can perform a cyclic operation of closing, conveying, opening, and closing the cable body in sequence.

[0016] Preferably, there are two sets of injection molding assemblies, which are arranged symmetrically. One of the injection molding assemblies includes a bracket arranged outside the fixed frame. A cylinder and a limiting frame are installed on the top of the bracket. An injection cylinder is slidably arranged on the top of the limiting frame. A drive plate is connected to the side wall of the injection cylinder. The output end of the cylinder is connected to the side wall of the drive plate. Multiple injection tube heads are connected to the output end of the injection cylinder. The input end of the injection cylinder is connected to an external plastic supply device.

[0017] Preferably, the fixed frame has movable grooves with the same structure on both symmetrical side walls, and the injection molding cylinder is movably arranged in the movable grooves.

[0018] Preferably, the drive assembly includes a motor mounted on the outer wall of the fixed frame, the output end of the motor being connected to a rotating rod, the rotating rod being rotatably arranged on the outer wall of the fixed frame, an upper worm and a lower worm being arranged on the rotating rod, and an upper worm wheel and a lower worm wheel of the same structure being rotatably arranged on the outer wall of the fixed frame; wherein the helical teeth of the upper worm and the lower worm are in opposite directions; the upper worm is meshed with the upper worm wheel, and the upper worm wheel is coaxially connected to the upper drive gear; the lower worm is meshed with the lower worm wheel, and the lower worm wheel is coaxially connected to the lower drive gear.

[0019] Preferably, the inner wall of the fixed frame is connected to multiple slide rails, and the inner cavity of the slide rails forms a sliding channel in a horizontal direction; the side wall of the upper horizontal moving frame is connected to a sliding plate, and the sliding plate is slidably arranged in the sliding channel of the slide rails; the upper horizontal moving frame is a rectangular frame structure, and the inner wall of the upper horizontal moving frame is vertically arranged with a slide rail structure; the side wall of the upper vertical moving frame is connected to a slider, and the upper vertical moving frame slides in cooperation with the slide rail structure through the slider; the top of the upper vertical moving frame is connected to a limiting plate, and the side wall of the limiting plate is rotatably connected to a limiting roller; the inner wall of the fixed frame is connected to two limiting blocks arranged vertically, the limiting blocks are rectangular block-shaped structures, and the limiting roller makes contact rolling cooperation with the side wall of the upper limiting block.

[0020] Preferably, after the upper mold and the lower mold are closed, the inner cavity forms multiple independent molding chambers. The molding chambers are used to form the shape of the bite block structure. The side walls of the upper mold and the lower mold are provided with multiple injection holes. Each injection hole is connected to each molding chamber. The injection tube head can be inserted into the injection hole.

[0021] Preferably, one of the inner cavities of the slide plate and the upper horizontal moving frame is provided with an airflow channel one, the inner cavity of the upper rectangular plate is provided with an airflow channel two, and the inner cavity of the upper mold is provided with a cooling channel; the end of the slide plate is connected to an external air supply device through a connecting pipe, the output end of the airflow channel one can be connected to or separated from the air inlet of the airflow channel two, and the output end of the airflow channel two is connected to the air inlet of the cooling channel; wherein, a hook-shaped plate is connected to the bottom of the upper horizontal moving frame, the inner cavity of the hook-shaped plate is provided with a jet channel, the end of the hook-shaped plate has an arc-shaped surface structure, the air inlet of the jet channel can be connected to or separated from the output end of the airflow channel one, and the output end of the jet channel is provided with multiple jet holes, which are arranged radially on the arc-shaped surface structure of the end of the hook-shaped plate.

[0022] Preferably, the inner wall of the airflow channel is fixedly connected with multiple raised rings, a flow block, and multiple sliding tracks; the air inlet of the jet channel is arranged between two of the raised rings, and a ring plate is slidably arranged between the two raised rings. When the ring plate is located at the side wall of one of the raised rings, the air inlet of the jet channel is closed; when the ring plate slides to the side wall of the other raised ring, the air inlet of the jet channel is opened; the inner cavities of the ring plate and the flow block are both breathable and perforated structures for airflow; a push rod is connected to the side wall of the ring plate. The movement extends through the sidewall of the flow block and is connected to a wedge-shaped block. The wedge-shaped block is slidably arranged on the sliding track, and the wedge-shaped block is connected to the flow block by a spring. A limit stop is connected to one end of the sliding track near the second airflow channel, and the limit stop is used to limit the sliding stroke of the wedge-shaped block. The sidewall of the wedge-shaped block has multiple air passages and is an inclined surface structure. When the upper rectangular plate rises, the sidewall of the upper rectangular plate can squeeze the inclined surface structure of the wedge-shaped block, pushing the wedge-shaped block to slide along the sliding track towards the flow block.

[0023] Compared with the prior art, the beneficial effects of the present invention are:

[0024] 1. This invention arranges multiple anti-biting blocks on the outer circumference of the cable body. The convex arc surface structure of the anti-biting blocks forms a priority biting point, preventing rats from directly biting the outer sheath and causing damage. At the same time, the glass crystals filled inside the anti-biting blocks have high hardness, which will cause rats to slip and feel pain when biting, so that they will give up biting. This solves the problem of rail transit cables being easily bitten and damaged by rats, causing short circuit faults.

[0025] 2. This invention designs a molding machine comprising a mold assembly, an injection molding assembly, and a guiding assembly. The prepared cable body is guided between the upper and lower molds via the guiding assembly. Synchronous counter-rotation of the upper and lower drive gears drives the upper and lower vertical moving frames to move synchronously in opposite directions, achieving mold closing between the upper and lower molds. After mold closing, the cable body is located within the mold cavity. Molten plastic mixed with glass crystals is injected into the mold cavity via the injection molding assembly, subsequently cooling and forming a locking block connected to the side wall of the outer sheath. The upper and lower drive gears continue to rotate synchronously in opposite directions, driving the upper vertical moving frame along with the upper horizontal moving frame, and the lower vertical moving frame along with the lower horizontal moving frame, to move synchronously forward horizontally. This achieves synchronous horizontal forward movement of the upper and lower molds in the mold-closed state. The upper and lower molds clamp the cable body, and the locking state formed by the cooled and molded bite blocks and the cavity allows the cable body to be synchronously conveyed forward one station distance, completing the forming of the bite blocks and the step-by-step feeding of the cable body. Then, the upper and lower drive gears continue to rotate synchronously in opposite directions, similarly driving the upper and lower vertical moving frames to move synchronously in opposite directions, realizing the opening of the upper and lower molds, and further realizing the resetting and closing of the upper and lower molds, entering the injection molding cycle of the next set of bite blocks. Through the synchronous reverse rectangular path movement of the upper and lower molds, the forming and feeding of one bite block at a time is achieved, matching the cable conveying and injection rhythm. There is no need to add an additional cable traction conveying mechanism, avoiding problems such as bite block position displacement, poor forming, and cable damage caused by the disconnection of the conveying and forming processes.

[0026] 3. This invention also incorporates a rectangular block-shaped limiting block designed on the inner wall of the fixed frame. The limiting roller rolls in contact with the side wall of the limiting block. When the upper and lower molds are in the closed state, the upper drive gear meshes with the teeth at the upper end of the annular groove of the upper vertical moving frame. At this time, the limiting roller is located at the bottom of the limiting block, thus restricting the vertical movement of the upper vertical moving frame and preventing it from moving upwards, which could lead to tooth dislodgement. Similarly, the lower mold is also restricted vertically to prevent it from moving downwards due to its own weight, which could also lead to tooth dislodgement. This effectively prevents the mold from floating or misaligning due to injection pressure during the mold closing and injection molding process, ensuring mold closing accuracy and cavity sealing. When the mold enters the horizontal conveying stage, the limiting roller rolls smoothly along the side wall of the limiting block, providing horizontal guidance for the upper vertical moving frame. This prevents vertical displacement of the upper vertical moving frame from causing tooth separation or skipping between the gear teeth and the upper drive gear. The same applies to the lower vertical moving frame. This achieves precise positioning and stable guidance of the mold throughout the entire cycle of mold closing, conveying, and opening. The upper and lower mold movements are highly synchronized and the trajectory does not deviate, avoiding tooth separation problems.

[0027] 4. This invention also arranges an airflow channel one in the inner cavity of the upper horizontal moving frame, an airflow channel two in the inner cavity of the upper rectangular plate, and a cooling channel in the inner cavity of the upper mold. When the external air supply equipment sends low-temperature airflow into the airflow channel one, and the mold is closed for injection molding, the airflow channel two of the upper rectangular plate is connected to the airflow channel one. At this time, the wedge block is held at the entrance of the airflow channel two by the elastic force of the spring, and is restricted from moving forward by the limiting block. The ring plate closes the air inlet of the jet channel. The low-temperature airflow only enters the cooling channel along the airflow channel two, and quickly cools and shapes the upper mold and the internal blocking block. The same applies to the lower mold, ensuring molding quality and demolding efficiency. When the mold opens and the upper rectangular plate rises, the side wall of the upper rectangular plate presses the inclined wedge block. The wedge block is pushed to slide towards the flow block against the elastic force of the spring, and then the ring plate is moved by the push rod to open the air inlet of the jet channel. At this time, the airflow channel one and airflow channel two are disconnected, and all the low-temperature airflow enters the jet channel and is ejected outward through the radially arranged jet holes. The position of the upper mold after opening is above the jet holes, so that the high-speed airflow ejected outward from the jet holes can blow clean and assist in cooling the molding cavity of the upper mold. The same applies to the lower mold, ensuring that the inner cavity of the mold remains in a low-temperature and clean state during the next mold closing and injection molding. The entire process relies on the movement of the mold itself to achieve automatic switching of the airflow path, without the need for additional electrical control and drive. The structure is simple, the operation is reliable, and cooling and cleaning are completed simultaneously. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the main cable structure of the present invention;

[0029] Figure 2 This is a schematic diagram of the cable body end face structure of the present invention;

[0030] Figure 3 This is a schematic diagram of the cross-sectional structure of the bite block of the present invention;

[0031] Figure 4 This is a schematic diagram of the molding machine structure of the present invention;

[0032] Figure 5 This is a schematic diagram of the injection molding component structure of the present invention;

[0033] Figure 6 This is a schematic diagram of the mold assembly structure of the present invention;

[0034] Figure 7 This is a cross-sectional view of the fixing frame structure of the present invention;

[0035] Figure 8 This is a schematic diagram of the guiding component structure of the present invention;

[0036] Figure 9 This is a schematic diagram of the drive component structure of the present invention;

[0037] Figure 10 This is a schematic diagram of the upper mold assembly and lower mold assembly of the present invention;

[0038] Figure 11 This is a schematic diagram of the limiting roller structure of the present invention;

[0039] Figure 12 This is a schematic diagram of the cross-sectional structure of the upper and lower molds of the present invention;

[0040] Figure 13 This is a schematic diagram of the molding chamber and injection hole structure of the upper and lower molds of the present invention;

[0041] Figure 14 This is a schematic diagram of the cooling channel structure of the present invention;

[0042] Figure 15 This is a cross-sectional structural diagram of the upper horizontal and upper vertical moving frames of the present invention;

[0043] Figure 16 for Figure 15 Enlarged schematic diagram of the structure at point A in the middle.

[0044] Explanation of the labels in the diagram:

[0045] 1. Cable body; 2. Anti-bite block; 3. Molding machine; 4. Mold assembly; 5. Injection molding assembly; 6. Guide assembly;

[0046] 101. Conductor core; 102. Insulation layer; 103. Flame retardant layer; 104. Inner sheath; 105. Armor layer; 106. Outer sheath; 201. Crystal wafer;

[0047] 41. Fixed frame; 42. Drive assembly; 43. Upper mold assembly; 44. Lower mold assembly; 45. Molding chamber; 46. Injection hole; 4101. Movable groove; 4102. Slide rail; 4103. Limiting block; 4201. Upper drive gear; 4202. Lower drive gear; 4203. Motor; 4204. Rotating rod; 4205. Upper worm gear; 4206. Lower worm gear; 4207. Upper worm wheel; 4208. Lower worm wheel; 4301. Upper horizontal moving frame; 4302. Upper vertical moving frame; 4303. Upper rectangular plate; 4304. Upper mold; 4305. Toothed edge; 4306. Slide plate; 43 4307. Slider; 4308. Limiting plate; 4309. Limiting roller; 4310. Airflow channel one; 4311. Airflow channel two; 4312. Cooling channel; 4313. Hook plate; 4314. Air jet channel; 4315. Air jet hole; 4316. Protruding ring; 4317. Flow block; 4318. Sliding track; 4319. Ring plate; 4320. Push rod; 4321. Wedge block; 4322. Elastic spring; 4323. Limiting stop block; 4324. Air passage; 4401. Lower horizontal moving frame; 4402. Lower vertical moving frame; 4403. Lower rectangular plate; 4404. Lower mold;

[0048] 501, bracket; 502, cylinder; 503, limit bracket; 504, injection cylinder; 505, drive plate; 506, injection tube head; 601, guide frame; 602, guide roller. Detailed Implementation

[0049] Example 1, as Figures 1 to 3 As shown, this embodiment provides a fire-resistant, flame-retardant, low-smoke, halogen-free power cable for rail transit, including a cable body 1. Multiple anti-biting blocks 2 are arranged on the outer circumference of the cable body 1. The cable body 1 also includes a conductor core 101, with an insulation layer 102 wrapped around the conductor core 101. A flame-retardant layer 103 is wrapped around the insulation layer 102, and an inner sheath 104 is wrapped around the flame-retardant layer 103. An armor layer 105 is wrapped around the inner sheath 104. The armor layer 105 is made of non-magnetic galvanized steel strip and has resistance to pressure, rodents, and electromagnetic interference. An outer sheath 106 is wrapped around the armor layer 105 and is made of low-smoke, halogen-free, flame-retardant polyolefin material, possessing environmental protection, halogen-free, low-smoke, flame-retardant, weather-resistant, and oil-resistant properties. This makes the cable body 1 a fire-resistant, flame-retardant, low-smoke, halogen-free power cable.

[0050] Specifically, multiple bite blocks 2 form a group, and each group of bite blocks 2 is arranged in a ring array on the outer circumference of the outer sheath 106. Multiple groups of bite blocks 2 are arranged in a linear manner. The bite blocks 2 are made of plastic, and their sidewalls are convex arc surfaces. The inner cavity of the bite blocks 2 is filled with multiple round crystals 201, which are granular spherical structures made of glass.

[0051] This invention addresses the problem of rodent-proof cables in rail transit systems by arranging multiple anti-biting blocks 2 on the outer circumference of the cable body 1. The convex arc surface of the anti-biting blocks 2 creates preferential biting points, preventing rats from directly biting the outer sheath 106 and causing damage. Simultaneously, the high hardness of the glass crystals 201 filling the anti-biting blocks 2 causes slippage and pain when rats bite, deterring them from further gnawing. This fundamentally solves the problem of rodent-proof cables in rail transit systems being easily damaged by rats, leading to short circuits. Furthermore, the combination of a ring array and linear arrangement of the anti-biting blocks 2 does not affect the cable's bending performance or laying flexibility. Combined with the low-smoke, halogen-free, flame-retardant polyolefin material of the outer sheath 106, this invention significantly improves the cable's rodent-proof capabilities and service life while retaining its fire-resistant, flame-retardant, low-smoke, and halogen-free environmentally friendly characteristics, ensuring the long-term safe and stable operation of the rail transit power supply system.

[0052] Example 2: This example provides a manufacturing process for a power cable, used to manufacture the power cable of Example 1, including the following steps:

[0053] S1. Conductor core preparation: Copper wire that meets national standards is selected as raw material. Multiple copper wires are twisted together at a specified pitch to form conductor core 101 using a stranding process. During the stranding process, the tension is controlled to be uniform to avoid wire breakage or loose strands. After stranding, the conductor core is surface polished to remove the oxide layer and impurities, ensuring that the conductor core has excellent conductivity and a smooth surface.

[0054] S2. Insulation layer coating operation: The prepared conductor core 101 is fed into the extruder. Cross-linked polyethylene is used as the insulation material. Under high temperature and high pressure, the insulation material is uniformly extruded and coated on the outside of the conductor core to form insulation layer 102. During the coating process, the extrusion temperature, speed and thickness are strictly controlled to ensure that the insulation layer is uniform in thickness, free of bubbles and damage, and that the insulation performance meets the design standards. After the coating is completed, cooling and shaping treatment is carried out.

[0055] S3. Flame-retardant layer coating operation: The wire core with the insulation layer 102 coated is fed into a special coating equipment. Flame-retardant polyolefin is selected as the flame-retardant material. The flame-retardant material is evenly coated on the outside of the insulation layer using a wrapping process to form the flame-retardant layer 103. During the wrapping process, the wrapping pitch and overlap rate are controlled to ensure that there are no missing or loose wrapping phenomena. During the extrusion process, the temperature and pressure are controlled to ensure that the flame-retardant layer is dense and firmly attached, so as to achieve a good flame-retardant effect.

[0056] S4. Inner sheath covering operation: After the flame retardant layer 103 is cooled and shaped, it is fed into the extruder. Polyvinyl chloride is selected as the inner sheath material. The inner sheath material is evenly extruded and covered on the outside of the flame retardant layer to form the inner sheath 104. During the covering process, the extrusion parameters are controlled to ensure that the inner sheath has a uniform thickness, a flat surface, and no scratches or damage. It plays the role of protecting the flame retardant layer and isolating moisture and impurities. After covering, it is cooled and cured.

[0057] S5. Armor layer wrapping operation: The wire core wrapped with the inner sheath 104 is sent into the armoring equipment. Galvanized steel strip is selected as the armor material. The wrapping process is adopted. The steel strip is evenly wrapped around the outside of the inner sheath according to the specified density and pitch to form the armor layer 105. During the wrapping process, the tension and wrapping angle are controlled to ensure that the armor layer is tight and flat, without loosening or breakage, thereby enhancing the mechanical strength, impact resistance and resistance to external damage of the cable.

[0058] S6. Outer Sheath Coating Operation: After the armor layer 105 is processed, it is fed into an extruder. Polyvinyl chloride (PVC) with excellent weather resistance and corrosion resistance is selected as the outer sheath material. The outer sheath material is evenly extruded and coated on the outside of the armor layer to form the outer sheath 106. During the coating process, the extrusion temperature, speed and thickness are strictly controlled to ensure that the outer sheath is free of bubbles and damage, has a smooth surface, and has good weather resistance, corrosion resistance and wear resistance. After the coating is completed, it is cooled and shaped.

[0059] S7. Finished product inspection and winding operation: Conduct comprehensive inspection of the prepared cable, including conductor resistance, insulation resistance, withstand voltage performance, flame retardant performance, mechanical properties and appearance quality inspection, and reject unqualified products.

[0060] S8. Injection molding operation of the bite block: Molten plastic containing glass particles is injected into the cavity that is attached to the side wall of the outer sheath 106 by the molding machine 3. After cooling and molding, the bite block 2 is formed and connected to the side wall of the outer sheath 106.

[0061] Example 3, as Figures 4 to 16 As shown, this embodiment provides a molding machine for implementing the preparation process in Embodiment 2. The molding machine 3 includes a mold assembly 4, an injection molding assembly 5, and a guide assembly 6. The assembly 4 includes a fixed frame 41, a drive assembly 42 is arranged on one side of the fixed frame 41, and an upper mold assembly 43 and a lower mold assembly 44 are arranged in the inner cavity of the fixed frame 41.

[0062] In an embodiment of the present invention, the drive assembly 42 includes an upper drive gear 4201 and a lower drive gear 4202 rotatably arranged on the inner sidewall of the fixed frame 41, and the upper drive gear 4201 and the lower drive gear 4202 are capable of synchronously rotating in opposite directions.

[0063] Specifically, the drive assembly 42 includes a motor 4203 mounted on the outer wall of the fixed frame 41. The output end of the motor 4203 is connected to a rotating rod 4204, which is rotatably arranged on the outer wall of the fixed frame 41. An upper worm 4205 and a lower worm 4206 are arranged on the rotating rod 4204. An upper worm wheel 4207 and a lower worm wheel 4208 with the same structure are rotatably arranged on the outer wall of the fixed frame 41. The helical teeth of the upper worm 4205 and the lower worm 4206 are in opposite directions. The upper worm 4205 is meshed with the upper worm wheel 4207, which is coaxially connected with the upper drive gear 4201. The lower worm 4206 is meshed with the lower worm wheel 4208, which is coaxially connected with the lower drive gear 4202.

[0064] The drive assembly 42 uses a motor 4203 as its power source. When the motor 4203 is running, it drives the rotating rod 4204 to rotate, which in turn drives the upper worm 4205 and the lower worm 4206 to rotate synchronously. The upper worm 4205 drives the upper worm wheel 4207 to rotate, which in turn drives the coaxial upper drive gear 4201 to rotate. The lower worm 4206 drives the lower worm wheel 4208 to rotate, which in turn drives the coaxial lower drive gear 4202 to rotate. With the help of the structural design of the two worm helical teeth in opposite directions, the upper drive gear 4201 and the lower drive gear 4202 can achieve synchronous reverse rotation. When the motor 4203 stops working, the rotation locking principle of the worm to the worm wheel can achieve instant self-locking of the upper drive gear 4201 and the lower drive gear 4202.

[0065] In another embodiment of the present invention, the upper mold assembly 43 includes an upper horizontal moving frame 4301 that is slidably arranged in the horizontal direction on the inner side wall of the fixed frame 41; specifically, a plurality of slide rails 4102 are connected to the inner side wall of the fixed frame 41, and the inner cavity of the slide rails 4102 forms a sliding channel in the horizontal direction; a slide plate 4306 is connected to the side wall of the upper horizontal moving frame 4301, and the slide plate 4306 is slidably arranged in the sliding channel of the slide rails 4102; thereby realizing the stable sliding of the upper horizontal moving frame 4301 in the horizontal direction.

[0066] In another embodiment of the present invention, an upper vertical moving frame 4302 is slidably arranged on the inner side of the upper horizontal moving frame 4301 in a vertical direction; specifically, the upper horizontal moving frame 4301 is a rectangular frame structure, and a slide rail structure is arranged on the inner side wall of the upper horizontal moving frame 4301 in a vertical direction. A slider 4307 is connected to the side wall of the upper vertical moving frame 4302, and the upper vertical moving frame 4302 slides in cooperation with the slide rail structure through the slider 4307; thus, stable sliding of the upper vertical moving frame 4302 in the vertical direction is achieved.

[0067] In another embodiment of the present invention, the bottom of the upper vertical moving frame 4302 is connected to the upper mold 4304 via the upper rectangular plate 4303, and the upper rectangular plate 4303 movably passes through the bottom of the upper horizontal moving frame 4301; wherein, the side wall of the upper vertical moving frame 4302 is provided with an annular groove, the annular groove is a rectangular groove structure, and a toothed opening 4305 is arranged on the annular groove, and the upper drive gear 4201 meshes with the toothed opening 4305.

[0068] Furthermore, the top of the upper vertical transfer frame 4302 is connected to a limiting plate 4308, and the side wall of the limiting plate 4308 is rotatably connected to a limiting roller 4309; the inner side wall of the fixed frame 41 is connected to two limiting blocks 4103 arranged vertically, the limiting blocks 4103 are rectangular block structures, and the limiting roller 4309 is in contact with the side wall of the upper limiting block 4103 in a rolling engagement; when the upper drive gear 4201 rotates, it can drive the upper vertical transfer frame 4302 to move the upper mold 4304 first in the horizontal direction and then in the vertical direction, forming a rectangular path motion state.

[0069] In this invention, the upper drive gear 4201 rotates continuously and meshes with the teeth 4305 on the annular groove of the upper vertical transfer frame 4302. In the first half of the gear's rotation, the meshing force preferentially pushes the upper vertical transfer frame 4302, together with the upper horizontal transfer frame 4301, to move horizontally in a straight line along the slide rail frame 4102. When the upper drive gear 4201 rotates to the vertical section of the teeth in the annular groove, the upper horizontal transfer frame 4301 just contacts and is limited to the side wall of the slide rail frame 4102, thus restricting horizontal displacement. The meshing force on the vertical section of the teeth... The upper vertical transfer frame 4302 is driven to move vertically along the vertical slide rail of the upper horizontal transfer frame 4301. As the upper drive gear 4201 continues to rotate, the upper vertical transfer frame 4302 drives the upper mold 4304 to perform a rectangular closed-loop motion trajectory. The contact rolling cooperation between the limiting roller 4309 and the side wall of the limiting block 4103 at the upper end ensures the stability of the rectangular closed-loop motion of the upper vertical transfer frame 4302 and prevents the tooth 4305 from disengaging from the upper drive gear 4201.

[0070] Furthermore, the lower mold assembly 44 and the upper mold assembly 43 are mutually symmetrical structural components. The lower mold assembly 44 includes a lower horizontal moving frame 4401, a lower vertical moving frame 4402, a lower rectangular plate 4403, and a lower mold 4404 arranged symmetrically with the upper mold assembly 43. When the lower drive gear 4202 rotates, the lower mold 4404 of the lower mold assembly 44 can similarly perform a rectangular path movement. When the upper drive gear 4201 and the lower drive gear 4202 rotate synchronously in opposite directions, the upper mold 4304 and the lower mold 4404 can sequentially perform a cycle of mold closing, conveying, mold opening, and mold closing again on the cable body 1.

[0071] This invention designs a molding machine comprising a mold assembly 4, an injection molding assembly 5, and a guide assembly 6. The prepared cable body 1 is guided by the guide assembly 6 into the space between the upper mold 4304 and the lower mold 4404 within the cavity of the fixing frame 41. The upper drive gear 4201 and the lower drive gear 4202 rotate synchronously in opposite directions, driving the upper vertical frame 4302 and the lower vertical frame 4402 to move synchronously towards each other, achieving mold closing between the upper mold 4304 and the lower mold 4404. After mold closing, the cable body 1 is located within the mold cavity and is then injected... Component 5 injects molten plastic mixed with glass crystals 201 into the mold cavity, which then cools and solidifies to form a locking block 2 connected to the side wall of the outer sheath 106. The upper drive gear 4201 and lower drive gear 4202 then continue to rotate synchronously in opposite directions, driving the upper vertical transfer frame 4302 along with the upper horizontal transfer frame 4301, and the lower vertical transfer frame 4402 along with the lower horizontal transfer frame 4401 to move forward horizontally synchronously. This achieves the synchronous forward movement of the upper mold 4304 and lower mold 4404 in the mold-closed state. The upper mold 4304 and lower mold 4404 clamp the cable body 1, and together with the cooled and formed bite block 2, they engage with the cavity, allowing the cable body 1 to be synchronously conveyed forward one station distance. This completes the forming of the bite block 2 and the step-by-step feeding of the cable body 1. Subsequently, the upper drive gear 4201 and lower drive gear 4202 continue to rotate synchronously in opposite directions, similarly driving the upper vertical frame 4302 and lower vertical frame 4402 to move synchronously in opposite directions, thus opening the upper mold 4304 and lower mold 4404, and continuing... The upper drive gear 4201 and the lower drive gear 4202 continue to rotate synchronously in opposite directions, further realizing the reset and mold closing of the upper mold 4304 and the lower mold 4404, and entering the injection molding cycle of the next set of bite blocks 2. The upper mold 4304 and the lower mold 4404 can perform synchronous and reverse rectangular path movement, realizing that one bite block 2 is formed and one is fed at a time. The cable conveying and injection rhythm are matched, and there is no need to add an additional cable traction conveying mechanism. This avoids the problems of bite block position displacement, poor molding, and cable damage caused by the disconnection between the conveying and molding processes.

[0072] The present invention also incorporates a rectangular block-shaped limiting block 4103 designed on the inner wall of the fixed frame 41. The limiting roller 4309 rolls in contact with the side wall of the limiting block 4103. When the upper mold 4304 and the lower mold 4404 are in the mold-closing state, the upper drive gear 4201 meshes with the tooth 4305 at the upper end of the annular groove of the upper vertical transfer frame 4302. At this time, the limiting roller 4309 is located at the bottom of the limiting block 4103, thus restricting the vertical movement of the upper vertical transfer frame 4302 and preventing it from moving upwards, which could lead to tooth dislodgement. Similarly, the lower mold 4404 is also restricted in the vertical direction to prevent it from moving upwards due to its own weight. The downward force causes tooth dislodgement; it effectively avoids mold floating and misalignment caused by injection pressure during mold closing and injection molding, ensuring mold closing accuracy and cavity sealing; when the mold enters the horizontal conveying stage, the limiting roller 4309 rolls smoothly along the side wall of the limiting block 4103, providing horizontal guidance for the upper vertical transfer frame 4302, preventing vertical displacement of the upper vertical transfer frame 4302 from causing tooth dislodgement or skipping between the toothed edge 4305 and the upper drive gear 4201, and the same applies to the lower vertical transfer frame 4402, realizing accurate positioning and stable guidance of the mold throughout the entire cycle of mold closing, conveying, and mold opening, with high synchronization of upper and lower mold movements and no trajectory deviation, avoiding tooth dislodgement problems.

[0073] In an embodiment of the present invention, there are two sets of injection molding components 5, which are arranged symmetrically. One of the injection molding components 5 includes a bracket 501 arranged on the outside of the fixed frame 41. A cylinder 502 and a limiting frame 503 are installed on the top of the bracket 501. An injection cylinder 504 is slidably arranged on the top of the limiting frame 503. A drive plate 505 is connected to the side wall of the injection cylinder 504. The output end of the cylinder 502 is connected to the side wall of the drive plate 505. A plurality of injection tube heads 506 are connected to the output end of the injection cylinder 504. The input end of the injection cylinder 504 is connected to an external plastic supply device. The fixed frame 41 has movable grooves 4101 with the same structure on both symmetrical side walls. The injection cylinder 504 is movably arranged in the movable grooves 4101.

[0074] Furthermore, after the upper mold 4304 and the lower mold 4404 are closed, multiple independent molding chambers 45 are formed in the inner cavity. The molding chambers 45 are used to form the structural shape of the bite block 2. Multiple injection holes 46 are opened on the side walls of the upper mold 4304 and the lower mold 4404. Each injection hole 46 is connected to each molding chamber 45. The injection tube head 506 can form an insertion fit with the injection hole 46.

[0075] In this invention, the injection cylinder 504 is a conventional constant-temperature storage cylinder capable of storing and maintaining the temperature of molten plastic. It can keep the molten plastic mixed with glass crystals 201 at a constant temperature to prevent premature solidification of the plastic and ensure the fluidity and uniformity of the molten plastic during injection. The external plastic supply equipment is used to continuously pump molten material into the injection cylinder 504 to provide injection pressure and ensure that the cavity is filled, free of air bubbles, and without material shortage. The cylinder 502 can drive the injection cylinder 504 to slide horizontally along the limit frame 503 through the drive plate 505, so that the injection tube head 506 is accurately inserted into the injection hole 46 of the mold to complete automatic alignment injection. After injection, it quickly retracts to avoid the mold opening and closing and transfer actions, realizing seamless connection between the injection process, mold movement, and cable transportation, ensuring multi-cavity synchronous injection, stable material output, and full molding.

[0076] In this embodiment of the invention, there are two guide components 6, which are symmetrically arranged on both sides of the fixing frame 41. One guide component 6 is used to guide the cable body 1 for feeding, and the other guide component 6 is used to guide the cable body 1 for discharging. The guide component 6 includes a guide frame 601, and multiple guide rollers 602 are arranged on the inner side wall of the guide frame 601. The multiple guide rollers 602 are arranged symmetrically in two rows, and a guide channel for conveying the cable body 1 is formed between every two upper and lower guide rollers 602. The side wall of the guide roller 602 has an inwardly concave arc structure, so that the guide channel forms a near-circular channel structure. It can fit tightly against the outer wall of the cable body 1, and center and limit the cable during feeding and discharging, ensuring that the cable always travels stably along a straight line at the center position of the mold. This provides reliable guidance for the high-precision forming of the ring array of the biting block 2, while reducing the cable conveying resistance and improving the smooth operation of the entire production line.

[0077] In an embodiment of the present invention, an airflow channel 4310 is arranged in the inner cavity of one of the slide plates 4306 and the inner cavity of the upper horizontal moving frame 4301; an airflow channel 4311 is arranged in the inner cavity of the upper rectangular plate 4303; and a cooling channel 4312 is arranged in the inner cavity of the upper mold 4304. The end of the slide plate 4306 is connected to an external air supply device via a connecting pipe. The external air supply device is used to supply low-temperature airflow to the airflow channel 4310. The output end of the airflow channel 4310 can be connected to or separated from the air inlet of the airflow channel 4311. The output end of channel 2 4311 is connected to the air inlet of cooling channel 4312; wherein, the bottom of the upper horizontal moving frame 4301 is connected to a hook plate 4313, the inner cavity of the hook plate 4313 is arranged with a jet channel 4314, the end of the hook plate 4313 is an arc-shaped surface structure, the air inlet of the jet channel 4314 can be connected or separated from the output end of airflow channel 1 4310, and the output end of the jet channel 4314 is arranged with multiple jet holes 4315, which are arranged radially on the arc-shaped surface structure at the end of the hook plate 4313.

[0078] In another embodiment of the present invention, the inner wall of the airflow channel 4310 is fixedly connected with a plurality of protruding rings 4316, a flow block 4317, and a plurality of sliding tracks 4318; the air inlet of the jet channel 4314 is arranged between two protruding rings 4316, and a ring plate 4319 is also slidably arranged between the two protruding rings 4316. When the ring plate 4319 is located at the side wall position of one of the protruding rings 4316, the air inlet of the jet channel 4314 is closed; when the ring plate 4319 slides to the side wall position of the other protruding ring 4316, the air inlet of the jet channel 4314 is opened; the inner cavities of the ring plate 4319 and the flow block 4317 are both breathable hollow structures for airflow; a push rod 4320 is connected to the side wall of the ring plate 4319. 320 is active through the side wall of the flow block 4317 and connected to a wedge block 4321. The wedge block 4321 is slidably arranged on the sliding track 4318. The wedge block 4321 and the flow block 4317 are connected by a spring spring 4322. A limit stop 4323 is connected to one end of the sliding track 4318 near the second airflow channel 4311. The limit stop 4323 is used to limit the sliding stroke of the wedge block 4321. The side wall of the wedge block 4321 has multiple air passages 4324. The side wall of the wedge block 4321 has an inclined surface structure. When the upper rectangular plate 4303 rises, the side wall of the upper rectangular plate 4303 can squeeze the inclined surface structure of the wedge block 4321 and push the wedge block 4321 to slide along the sliding track 4318 towards the flow block 4317.

[0079] The present invention further includes an airflow channel 4310 arranged in the inner cavity of the upper horizontal moving frame 4301, an airflow channel 4311 arranged in the inner cavity of the upper rectangular plate 4303, and a cooling channel 4312 arranged in the inner cavity of the upper mold 4304. When an external air supply device sends low-temperature airflow into the airflow channel 4310, and the mold is closed for injection molding, the airflow channel 4311 of the upper rectangular plate 4303 is connected to the airflow channel 4310. At this time, the wedge block 4321 is subjected to the elastic spring 4322. The elastic force keeps the upper mold 4304 at the entrance of the second airflow channel 4311, where it is restricted from moving forward by the limiting block 4323. The ring plate 4319 closes the air inlet of the jet channel 4314, and the low-temperature airflow only enters the cooling channel 4312 along the second airflow channel 4311 to quickly cool and solidify the upper mold 4304 and the internal blocking block 2. The same applies to the lower mold 4404, ensuring molding quality and demolding efficiency. When the mold opens and the upper rectangular plate 4303 rises, the upper rectangular plate 430... The inclined surface of the sidewall pressing wedge block 4321 is pushed to overcome the elastic force of the elastic spring 4322 and slide towards the flow block 4317. Then, the push rod 4320 drives the ring plate 4319 to move, opening the air inlet of the jet channel 4314. At this time, the airflow channel 1 4310 and the airflow channel 2 4311 are disconnected. All the low-temperature airflow enters the jet channel 4314 and is ejected outward through the radially arranged jet holes 4315. After the upper mold 4304 is opened, its position is above the jet holes 4315, so that the high-speed airflow ejected outward from the jet holes 4315 can blow clean and assist in cooling the molding chamber 45 of the upper mold 4304. The same applies to the lower mold 4404, ensuring that the inner cavity of the mold remains in a low-temperature and clean state during the next mold closing and injection molding. The entire process relies on the movement of the mold itself to achieve automatic switching of the airflow path, without the need for additional electrical control and drive. The structure is simple, the action is reliable, and cooling and cleaning are completed simultaneously.

[0080] The embodiments disclosed in this invention are preferred embodiments, but are not limited thereto. Those skilled in the art can easily understand the spirit of this invention based on the above embodiments and make different extensions and variations, but as long as they do not depart from the spirit of this invention, they are all within the protection scope of this invention.

Claims

1. A fire-resistant, flame-retardant, low-smoke, halogen-free power cable for rail transit, characterized in that, Includes a cable body (1), and multiple anti-bite blocks (2) are arranged on the outer circumference of the cable body (1). The cable body (1) also includes a conductor core (101), the conductor core (101) is wrapped with an insulation layer (102), the insulation layer (102) is wrapped with a flame-retardant layer (103), the flame-retardant layer (103) is wrapped with an inner sheath (104), the inner sheath (104) is wrapped with an armor layer (105), and the armor layer (105) is wrapped with an outer sheath (106). Multiple bite blocks (2) form a group, and each group of bite blocks (2) is arranged in a ring array on the outer circumference of the outer sheath (106). Multiple groups of bite blocks (2) are arranged in a linear manner. The sidewall of the bite block (2) is a convex arc surface structure. The inner cavity of the bite block (2) is filled with multiple round crystals (201). The round crystals (201) are granular spherical structures made of glass.

2. A manufacturing process for an electric cable, used to manufacture the electric cable according to claim 1, characterized in that, Includes the following steps: S1. Conductor core preparation: Multiple copper wires are twisted together at a specified pitch to form a conductor core (101) using a stranding process. S2. Insulation layer coating operation: The prepared conductor core (101) is fed into the extruder. Under high temperature and high pressure, the insulating material is uniformly extruded and coated on the outside of the conductor core to form an insulation layer (102). S3. Flame retardant layer coating operation: The wire core with the insulation layer (102) wrapped is sent into the coating equipment. The flame retardant material is evenly wrapped on the outside of the insulation layer by the wrapping process to form a flame retardant layer (103). S4. Inner sheath covering operation: After the flame retardant layer (103) is cooled and shaped, it is fed into the extruder to uniformly extrude and cover the outside of the flame retardant layer (103) to form the inner sheath (104). S5. Armor layer wrapping operation: The wire core with the inner sheath (104) wrapped is sent into the armoring equipment. The steel strip is wrapped evenly on the outside of the inner sheath according to the specified density and pitch using the wrapping process to form the armor layer (105). S6. Outer sheath covering operation: After the armor layer (105) is processed, it is fed into the extruder to uniformly extrude and cover the outer side of the armor layer (105) to form an outer sheath (106). S7. Finished product inspection and winding operation: Inspect the prepared cables and remove unqualified products. S8. Injection molding operation of the bite block: Molten plastic containing glass particles is injected into the cavity attached to the side wall of the outer sheath (106) by the molding machine (3). After cooling and molding, the bite block (2) is formed on the side wall of the outer sheath (106).

3. The manufacturing process of the power cable according to claim 2, characterized in that, The molding machine (3) includes a mold assembly (4), an injection molding assembly (5), and a guide assembly (6); The mold assembly (4) includes a fixing frame (41), a driving assembly (42) is arranged on one side of the fixing frame (41), and an upper mold assembly (43) and a lower mold assembly (44) are arranged in the inner cavity of the fixing frame (41). The drive assembly (42) includes an upper drive gear (4201) and a lower drive gear (4202) rotatably arranged on the inner sidewall of the fixed frame (41), and the upper drive gear (4201) and the lower drive gear (4202) are capable of synchronously rotating in opposite directions; The upper mold assembly (43) includes an upper horizontal sliding frame (4301) that is slidably arranged in the horizontal direction on the inner side wall of the fixed frame (41), an upper vertical sliding frame (4302) that is slidably arranged in the vertical direction on the inner side of the upper horizontal sliding frame (4301), and an upper mold (4304) that is connected to the bottom of the upper vertical sliding frame (4302) through an upper rectangular plate (4303). The upper vertical moving frame (4302) has an annular groove on its side wall. The annular groove is a rectangular groove structure. A toothed slot (4305) is arranged on the annular groove. The upper driving gear (4201) meshes with the toothed slot (4305). When the upper driving gear (4201) rotates, it can drive the upper vertical moving frame (4302) to move the upper mold (4304) first in the horizontal direction and then in the vertical direction, forming a rectangular path motion state. The lower mold assembly (44) includes a lower horizontal moving frame (4401), a lower vertical moving frame (4402), a lower rectangular plate (4403), and a lower mold (4404) arranged symmetrically with the upper mold assembly (43); when the lower drive gear (4202) rotates, the lower mold (4404) of the lower mold assembly (44) can similarly perform a rectangular path motion state; When the upper drive gear (4201) and the lower drive gear (4202) rotate synchronously in opposite directions, the upper mold (4304) and the lower mold (4404) can perform a cyclic operation of closing, conveying, opening and closing the cable body (1) in sequence.

4. The manufacturing process of the power cable according to claim 3, characterized in that, There are two sets of injection molding components (5), and the two sets of injection molding components (5) are arranged in a symmetrical structure. One of the injection molding components (5) includes a bracket (501) arranged on the outside of the fixed frame (41). A cylinder (502) and a limit frame (503) are installed on the top of the bracket (501). An injection cylinder (504) is slidably arranged on the top of the limit frame (503). A drive plate (505) is connected to the side wall of the injection cylinder (504). The output end of the cylinder (502) is connected to the side wall of the drive plate (505). Multiple injection tube heads (506) are connected to the output end of the injection cylinder (504). The input end of the injection cylinder (504) is connected to an external plastic supply device.

5. The manufacturing process of the power cable according to claim 4, characterized in that, The fixed frame (41) has movable grooves (4101) with the same structure on both symmetrical side walls, and the injection cylinder (504) is movably arranged in the movable grooves (4101).

6. The manufacturing process of the power cable according to claim 3, characterized in that, The drive assembly (42) includes a motor (4203) mounted on the outer wall of the fixed frame (41). The output end of the motor (4203) is connected to a rotating rod (4204). The rotating rod (4204) is rotatably arranged on the outer wall of the fixed frame (41). An upper worm (4205) and a lower worm (4206) are arranged on the rotating rod (4204). An upper worm wheel (4207) and a lower worm wheel (4208) with the same structure are rotatably arranged on the outer wall of the fixed frame (41). The upper worm (4205) and the lower worm (4206) have helical teeth in opposite directions; The upper worm (4205) is meshed with the upper worm wheel (4207), and the upper worm wheel (4207) is coaxially connected with the upper drive gear (4201); The lower worm (4206) is meshed with the lower worm wheel (4208), and the lower worm wheel (4208) is coaxially connected with the lower drive gear (4202).

7. The manufacturing process of the power cable according to claim 3, characterized in that, The inner wall of the fixed frame (41) is connected to a plurality of slide rail frames (4102), and the inner cavity of the slide rail frame (4102) forms a sliding channel in the horizontal direction; The upper horizontal moving frame (4301) has a sliding plate (4306) connected to its side wall, and the sliding plate (4306) is slidably arranged in the sliding channel of the slide rail frame (4102); The upper horizontal moving frame (4301) is a rectangular frame structure. The inner side wall of the upper horizontal moving frame (4301) is arranged with a slide rail structure in a vertical direction. The side wall of the upper vertical moving frame (4302) is connected with a slider (4307). The upper vertical moving frame (4302) slides with the slide rail structure through the slider (4307). The top of the upper vertical moving frame (4302) is connected to a limiting plate (4308), and the side wall of the limiting plate (4308) is rotatably connected to a limiting roller (4309). The inner wall of the fixed frame (41) is connected to two limiting blocks (4103) arranged vertically. The limiting blocks (4103) are rectangular block structures. The limiting roller (4309) is in contact with the side wall of the limiting block (4103) at the upper end of the limiting roller (4309) in a rolling contact manner.

8. The manufacturing process of the power cable according to claim 4, characterized in that, After the upper mold (4304) and the lower mold (4404) are closed, multiple independent molding chambers (45) are formed in the inner cavity. The molding chambers (45) are used to form the structural shape of the bite block (2). Multiple injection holes (46) are opened on the side walls of the upper mold (4304) and the lower mold (4404). Each injection hole (46) is connected to each molding chamber (45). The injection tube head (506) can be inserted into the injection hole (46).

9. The manufacturing process of the power cable according to claim 7, characterized in that, One of the slide plates (4306) and the upper horizontal moving frame (4301) are provided with an airflow channel one (4310), the upper rectangular plate (4303) is provided with an airflow channel two (4311), and the upper mold (4304) is provided with a cooling channel (4312). The end of the slide plate (4306) is connected to an external air supply device through a connecting pipe. The output end of the first airflow channel (4310) can be connected or separated from the air inlet of the second airflow channel (4311). The output end of the second airflow channel (4311) is connected to the air inlet of the cooling channel (4312). The upper horizontal moving frame (4301) is connected to a hook plate (4313) at its bottom. The hook plate (4313) has an air jet channel (4314) arranged inside its cavity. The end of the hook plate (4313) is an arc-shaped surface structure. The air inlet of the air jet channel (4314) can be connected or separated from the output end of the airflow channel (4310). The output end of the air jet channel (4314) is provided with multiple air jet holes (4315). The air jet holes (4315) are arranged radially on the arc-shaped surface structure at the end of the hook plate (4313).

10. The manufacturing process of the power cable according to claim 9, characterized in that, The inner wall of the airflow channel (4310) is fixedly connected with multiple protruding rings (4316), flow blocks (4317) and multiple sliding tracks (4318). The air inlet of the jet passage (4314) is arranged between the two protruding rings (4316), and a ring plate (4319) is also slidably arranged between the two protruding rings (4316). When the ring plate (4319) is located on the side wall of one of the protruding rings (4316), the air inlet of the jet passage (4314) is closed. When the ring plate (4319) slides to the side wall of the other protruding ring (4316), the air inlet of the jet passage (4314) is opened. The inner cavities of the ring plate (4319) and the flow block (4317) are both breathable and hollow structures for airflow. A push rod (4320) is connected to the side wall of the ring plate (4319). The push rod (4320) moves through the side wall of the flow block (4317) and is connected to a wedge block (4321). The wedge block (4321) is slidably arranged on the sliding track (4318). The wedge block (4321) and the flow block (4317) are connected by a spring spring (4322). The sliding track (4318) is connected to a limit block (4323) at one end near the second airflow channel (4311). The limit block (4323) is used to limit the sliding stroke of the wedge block (4321). The wedge block (4321) has multiple air passages (4324) on its sidewall. The sidewall of the wedge block (4321) has an inclined surface structure. When the upper rectangular plate (4303) rises, the sidewall of the upper rectangular plate (4303) can squeeze the inclined surface structure of the wedge block (4321) and push the wedge block (4321) to slide along the sliding track (4318) toward the flow block (4317).

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