A high-temperature-resistant halogen-free low-smoke electric wire cable

Abstract

This invention discloses a high-temperature resistant halogen-free low-smoke wire and cable, relating to the field of wire and cable technology. It includes multiple cores, with a filling layer on the outer surface of each core to fill the gaps between them. In use, the high-temperature resistant layer is located between the outer insulation layer and the shielding layer, enabling bidirectional heat interception. Utilizing passive automatic cooling, it requires no external power or circuit control. When the cable temperature reaches the phase change temperature, it automatically triggers an endothermic reaction, rapidly reducing the internal temperature of the cable. Combined with the elastic thermally conductive filler, it quickly and uniformly conducts heat, shortening the heat transfer path and improving the response speed and uniformity of heat absorption and cooling. This effectively inhibits the softening, melting, and cracking of the outer insulation layer and the inner insulation layer of the cores due to high temperatures, ensuring that the cable maintains stable electrical and mechanical properties under high-temperature conditions.

Description

Technical Field

[0001] This invention relates to the field of wire and cable technology, specifically to a high-temperature resistant halogen-free low-smoke wire and cable. Background Technology

[0002] Wires and cables are wire products used to transmit electrical energy, electrical signals, and realize electromagnetic energy conversion. Halogen-free low-smoke wires and cables are special cables that meet the core characteristics of being halogen-free, low-smoke, and flame-retardant. Unlike traditional halogen-containing cables, they do not release toxic hydrogen halide gas when burning, have extremely low smoke density, and possess flame-retardant and even fire-resistant capabilities. Their core function is to reduce the release of toxic and harmful smoke in fire scenarios, reduce visibility obstruction, delay the spread of fire, buy time for personnel evacuation and fire rescue, and reduce secondary hazards after a fire. They are safety upgrade cables for fields such as construction, transportation, and energy.

[0003] In practical use, halogen-free low-smoke wires and cables often face various high-temperature scenarios, such as long-term high-temperature baking in the external environment, instantaneous high temperatures generated during short-circuit faults, or external high-temperature burning in the early stages of a fire. The insulation layer of ordinary halogen-free low-smoke cables is mostly made of halogen-free polyolefins, cross-linked polyethylene, and other materials. Although these materials can meet the requirements of halogen-free, low-smoke, and flame-retardant properties, they have a low heat resistance limit. When the cable is exposed to high-temperature scenarios for a long time, the insulation layer is prone to softening, melting, deformation, or even cracking and damage, leading to a decrease in insulation performance and problems such as leakage and short circuits. In severe cases, it can cause cable failure.

[0004] Therefore, we propose a high-temperature resistant halogen-free low-smoke wire and cable to solve the problems mentioned in the background art. Summary of the Invention

[0005] The purpose of this invention is to provide a high-temperature resistant halogen-free low-smoke wire and cable to solve the problem that the heat resistance limit of ordinary halogen-free low-smoke cables mentioned in the background art is low. When the cable is in a high-temperature environment for a long time, the insulation layer is prone to softening, melting, deformation, or even cracking and damage, which leads to a decrease in insulation performance and problems such as leakage and short circuit. In severe cases, it can cause cable failure.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a high-temperature resistant halogen-free low-smoke wire and cable, comprising multiple cores, wherein the outer surface of the multiple cores is provided with a filling layer for filling the gaps between the multiple cores, the outer surface of the filling layer is provided with an outer insulation layer for core insulation protection, and further comprising a high-temperature resistant layer, which is closely attached to the outer surface of the outer insulation layer for bidirectional heat interception, wherein the high-temperature resistant layer comprises a high-temperature resistant base layer, which is closely attached to and covers the outside of the outer insulation layer; The heat-absorbing and cooling component is provided in multiple forms. Each heat-absorbing and cooling component includes a fixing block and a shape memory polymer. Three micro phase change capsules are equidistantly arranged on both outer surfaces of the fixing block. These capsules are used to passively trigger heat absorption and quickly reduce the internal temperature of the cable. Two expansion plates are movably embedded inside the fixing block. A fixing plate is fixedly connected to the outer surface of each micro phase change capsule. Two fixing rods are fixedly installed on the outer surface of each fixing plate. A conical spring is fixedly connected to the center of the outer surface of each fixing plate. Multiple connectors are provided for connecting two adjacent heat-absorbing and cooling components; Each of the microphase change capsules includes a capsule wall, and the capsule wall contains a capsule core made of composite phase change material to accelerate the phase change reaction rate.

[0007] Preferably, an elastic thermally conductive filler is used to fill the interior of the high-temperature resistant base layer to provide flexible support for the heat-absorbing and cooling components and to quickly and evenly transfer the heat transferred by the high-temperature resistant base layer to the heat-absorbing and cooling components. The high-temperature resistant base layer is made of halogen-free, low-smoke, flame-retardant polyolefin substrate and is mixed with inorganic flame retardants such as aluminum hydroxide and magnesium hydroxide.

[0008] Preferably, the outer surfaces of the shape memory polymer on both sides are fixedly connected to the outer surfaces of one side of the two expansion plates. Under the expansion thrust of the shape memory polymer, the two expansion plates are forced to move in opposite directions, and the micro phase change capsule is pushed to move towards the inner wall of the high temperature resistant layer by the fixing rod and the fixing plate.

[0009] Preferably, two guide rails are fixedly installed at the top and bottom of the fixed block, and two grooves are opened at the top and bottom of the two expansion plates. The eight grooves are arranged in groups of two in each longitudinal direction, and the outer surfaces of the four guide rails are respectively movably embedded in the interior of the four groups of grooves.

[0010] Preferably, the outer surfaces of both sides of the fixing block are provided with multiple movable holes, and the outer surface of each fixing rod is movably embedded in the movable hole. The six conical springs are arranged in groups of three vertically distributed.

[0011] Preferably, one end of each of the two sets of conical springs is fixedly connected to the outer surfaces of both sides of the fixing block, and the multiple fixing rods are arranged in groups of six vertically distributed, with one end of each of the two sets of fixing rods fixedly connected to the outer surfaces of the other side of the two extension plates.

[0012] Preferably, each of the connectors includes a first connecting block and a second connecting block. One end of the first connecting block is fixedly fitted with an elastic ball, and one end of the second connecting block is fixedly fitted with an elastic ball sleeve. The outer surface of the elastic ball is movably embedded inside the elastic ball sleeve. The outer surface of the elastic ball sleeve has a locking hole. The outer surface of one end of the first connecting block is movably embedded inside the locking hole. The outer surfaces of the first connecting block and the second connecting block are respectively fixedly installed on the outer surfaces of two adjacent fixed blocks.

[0013] Preferably, the outer surface of the elastic thermally conductive filler is provided with multiple mounting grooves, and each heat-absorbing and cooling component is embedded inside the mounting groove. The outer surface of the elastic thermally conductive filler is provided with multiple connecting grooves, and each connecting component is embedded inside the connecting groove.

[0014] Preferably, the outer surface of the high-temperature resistant layer is provided with a shielding layer for shielding external electromagnetic interference, the outer surface of the shielding layer is provided with an inner protective layer for isolating mechanical damage and preventing the intrusion of water, oil and impurities, the outer surface of the inner protective layer is provided with an armor layer for protecting the inner protective layer, and the outer surface of the armor layer is provided with an outer sheath layer for protecting the internal structure of the cable.

[0015] Preferably, each of the wire cores includes a conductor, the outer surface of which is provided with an inner insulation layer for electrical isolation of the conductor, and the outer surface of which is provided with a wrapping layer for protecting the inner insulation layer. The inner insulation layer is made of halogen-free cross-linked polyethylene material with added inorganic flame retardant, and the wrapping layer is made of halogen-free flame-retardant glass fiber tape, which is overlapped and wrapped around the outer surface of the inner insulation layer.

[0016] Compared with the prior art, the beneficial effects of the present invention are: 1. When this invention is used, the high-temperature resistant layer is located between the outer insulation layer and the shielding layer. It can intercept heat in both directions and utilize passive automatic cooling without the need for external power or circuit control. When the cable temperature reaches the phase change temperature, it automatically triggers an endothermic reaction, which quickly reduces the internal temperature of the cable. Combined with the elastic thermally conductive filler, it can quickly and evenly conduct heat, shorten the heat transfer path, and improve the response speed and uniformity of heat absorption and cooling. It effectively inhibits the softening, melting, and cracking of the outer insulation layer and the inner insulation layer of the core due to high temperature, ensuring that the cable can still maintain stable electrical and mechanical properties under high-temperature conditions.

[0017] 2. When the annular multi-point heat absorption and cooling components are arranged in an orderly manner with the top and bottom aligned, a symmetrical support frame can be formed, which can effectively buffer the mechanical stress during cable bending and laying, and improve the service life of the high-temperature resistant layer. When the annular multi-point heat absorption and cooling components are distributed alternately, they can fill the longitudinal gaps and form a denser heat absorption network to absorb heat in all directions.

[0018] 3. When this invention is used, the shape memory polymer expands when heated, pushing the extension plate to move. The fixing rod pushes the fixing plate and the micro phase change capsule to move, so that the micro phase change capsule is tightly attached to the inner walls on both sides of the high-temperature resistant base layer, increasing the contact area, accelerating the heat transfer speed, and improving the cooling efficiency. The expansion action of the shape memory polymer adapts to the slight deformation of the cable caused by thermal expansion and contraction, ensuring that the heat absorption and cooling function is continuously effective. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of a high-temperature resistant halogen-free low-smoke wire and cable according to the present invention. Figure 2 This is a schematic diagram of the core structure of a high-temperature resistant halogen-free low-smoke wire and cable according to the present invention. Figure 3 This is a schematic diagram of the internal structure of the high-temperature resistant layer in a high-temperature resistant halogen-free low-smoke wire and cable of the present invention. Figure 4 This is a schematic diagram of the structure of the elastic thermally conductive filler in a high-temperature resistant halogen-free low-smoke wire and cable according to the present invention. Figure 5 This is a schematic diagram of the heat-absorbing and cooling component in a high-temperature resistant halogen-free low-smoke wire and cable according to the present invention. Figure 6 This is a schematic diagram of the connector structure in a high-temperature resistant halogen-free low-smoke wire and cable according to the present invention; Figure 7 This is a cross-sectional schematic diagram of the fixing block in a high-temperature resistant halogen-free low-smoke wire and cable according to the present invention. Figure 8 This is a schematic diagram showing the unfolded structure of the extension plate in a high-temperature resistant halogen-free low-smoke wire and cable according to the present invention. Figure 9 This is a schematic diagram showing the different angular distributions of heat-absorbing and cooling components in a high-temperature resistant halogen-free low-smoke wire and cable according to the present invention.

[0020] In the picture: 1. Core wire; 101. Conductor; 102. Inner insulation layer; 103. Wrapping layer; 2. Filler layer; 3. Outer insulation layer; 4. High-temperature resistant layer; 41. High-temperature resistant base layer; 42. Elastic thermally conductive filler; 43. Heat-absorbing and cooling component; 431. Fixing block; 432. Micro-phase change capsule; 4321. Capsule wall; 4322. Capsule core; 433. Expansion plate; 434. Fixing piece; 435. Fixing rod; 436. Conical spring; 437. Movable hole; 438. Shape memory polymer; 439. Guide slide; 4310. Slide groove; 44. Connector; 441. First connecting block; 442. Second connecting block; 443. Elastic ball sleeve; 444. Engaging hole; 445. Elastic ball; 45. Mounting groove; 46. Connecting groove; 5. Shielding layer; 6. Inner sheath; 7. Armor layer; 8. Outer sheath layer. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Please see Figures 1-9 As shown, the present invention provides a technical solution: A high-temperature resistant halogen-free low-smoke wire and cable includes multiple cores 1, a filling layer 2 for filling the gaps between the multiple cores 1 on the outer surface of the multiple cores 1, an outer insulation layer 3 for overall insulation protection of the cores 1 on the outer surface of the filling layer 2, and a high-temperature resistant layer 4 that is closely attached to the outer surface of the outer insulation layer 3 for bidirectional heat interception. The high-temperature resistant layer 4 includes a high-temperature resistant base layer 41 that is closely attached to and covers the outside of the outer insulation layer 3. The heat absorption and cooling component 43 is provided in multiple ways. Each heat absorption and cooling component 43 includes a fixing block 431 and a shape memory polymer 438. Three micro phase change capsules 432 are equidistantly arranged on both outer surfaces of the fixing block 431. These capsules are used to passively trigger heat absorption and quickly reduce the internal temperature of the cable. Two expansion plates 433 are movably embedded inside the fixing block 431. A fixing plate 434 is fixedly connected to the outer surface of each micro phase change capsule 432. Two fixing rods 435 are fixedly installed on the outer surface of each fixing plate 434. A conical spring 436 is fixedly connected to the center of the outer surface of each fixing plate 434. Multiple connectors 44 are provided for connecting two adjacent heat-absorbing and cooling components 43; Each microphase change capsule 432 includes a capsule wall 4321, and a capsule core 4322 is disposed inside the capsule wall 4321. The core is made of composite phase change material and is used to accelerate the phase change reaction rate.

[0023] The elastic thermally conductive filler 42 is filled inside the high-temperature resistant base layer 41 to provide flexible support for the heat-absorbing and cooling component 43 and to quickly and evenly transfer the heat transferred by the high-temperature resistant base layer 41 to the heat-absorbing and cooling component 43. The high-temperature resistant base layer 41 is made of halogen-free, low-smoke, flame-retardant polyolefin substrate and is mixed with inorganic flame retardants such as aluminum hydroxide and magnesium hydroxide.

[0024] In practical applications, multiple heat-absorbing and cooling components 43 are arranged in multiple rows, each row in a circular array, forming a ring-shaped multi-point heat absorption and cooling system. A corresponding number of connectors 44 are matched according to the number of heat-absorbing and cooling components 43 to connect each row of heat-absorbing and cooling components 43 into a whole. Figure 5As shown. Multiple microphase change capsules 432 are distinguished by their inner and outer circles, and their structural shapes differ slightly, such as... Figure 7 As shown, the outer surface of the micro-phase change capsules 432 distributed on the inner circle is concave and arc-shaped, contacting the inner circular sidewall of the high-temperature resistant base layer 41. The outer surface of the micro-phase change capsules 432 distributed on the outer circle is convex and arc-shaped, contacting the outer circular sidewall of the high-temperature resistant base layer 41. When the cable temperature rises to the phase change temperature (70-100℃) of the microcapsule core 4322, the core material 4322 undergoes a phase change, changing from solid to liquid, passively absorbing a large amount of heat, achieving a rapid decrease in the internal temperature of the cable, and preventing the outer insulation layer 3 from softening and melting due to high temperature. The high-temperature resistant base layer 41 uses a halogen-free, low-smoke, flame-retardant polyolefin substrate, mixed with aluminum hydroxide and magnesium hydroxide inorganic flame retardants. The mixing ratio of aluminum hydroxide and magnesium hydroxide is 1:1-2:1, and the total addition amount is 22%-42% of the substrate mass. At the same time, 0.6%-1.2% of anti-aging agent is added. While the micro-phase change capsule 432 absorbs heat and cools down during phase change, the added inorganic flame retardant decomposes at high temperature, releasing water vapor, further absorbing heat, diluting combustible gases, and inhibiting the rise in cable temperature. When the cable temperature drops below the phase change temperature, the capsule core 4322 material returns to solid state, which can again absorb heat and cool down, forming a cycle of protection. The high-temperature resistant layer 4 inhibits the rise in cable temperature by passively triggering heat absorption and cooling, protecting the electrical performance of the insulation layer. It also has halogen-free, low-smoke, and flame-retardant functions, working synergistically with the insulation layer to improve the overall environmental and safety performance of the cable. It is tightly attached to the insulation layer, which can reduce heat transfer. The core 4322 is made of paraffin wax and polyethylene glycol in a mass ratio of 7:3-8:2 to form a composite phase change material. It also contains 0.5%-1% of a halogen-free phase change accelerator. The phase change temperature of paraffin wax is 70-102℃, and that of polyethylene glycol is 55-65℃. Polyethylene glycol can trigger heat absorption in advance when the cable temperature reaches 55-65℃, while paraffin wax continues to absorb heat at 70-102℃, forming a stepped heat absorption and cooling effect. Utilizing this dual-temperature-range triggering of heat absorption prevents rapid temperature spikes in the cable and improves the timeliness of the cooling response. The added phase change accelerator shortens the phase change reaction time, ensuring that the micro-phase change capsule 432 responds quickly to temperature changes and improves cooling efficiency. Furthermore, compared to single phase change materials, the composite phase change material has a larger heat absorption capacity and a more lasting cooling effect.

[0025] Furthermore, the heat-absorbing and cooling component 43 is installed inside the high-temperature resistant base layer 41 through the elastic thermally conductive filler 42, forming a flexible support for the heat-absorbing and cooling component 43 to prevent it from being suspended or shaking. At the same time, it buffers the mechanical stress when the cable is bent, protecting the microcapsule wall 4321 from being squeezed and damaged. The matrix and flame retardant used in the elastic thermally conductive filler 42 are both halogen-free systems, which meet the overall environmental protection requirements of the cable. The elastic thermally conductive filler 42 has high thermal conductivity, which can quickly and evenly conduct the high temperature transferred by the high-temperature resistant base layer 41 to all the heat-absorbing and cooling components 43, shortening the heat transfer path and improving the response speed and uniformity of heat absorption and cooling. The high-temperature resistant base layer 41, the elastic thermally conductive filler 42, and the heat-absorbing and cooling component 43 work together to achieve a closed loop of rapid temperature conduction, efficient heat absorption, and auxiliary flame retardancy, which greatly improves the cooling efficiency and response speed of the high-temperature resistant layer 4 and forms a circulating thermal protection.

[0026] To further explain, when the upper and lower rows of heat-absorbing and cooling components 43 are as follows: Figure 9 As shown in Figure a, when the upper and lower rows are aligned in an orderly manner, a symmetrical support frame is formed in the circumferential direction of the cable, resulting in uniform stress distribution. This effectively buffers the mechanical stress during cable bending and laying, preventing localized stress concentration that could lead to damage to the micro-phase change capsule 432, and improving the overall structural strength and service life of the high-temperature resistant layer 4. When the upper and lower rows of heat-absorbing and cooling components 43 are arranged as follows: Figure 9 As shown in Figure b, when the upper and lower positions are staggered, they can fill the longitudinal gaps that exist when they are aligned, forming a denser heat-absorbing network in the circumferential direction of the cable, ensuring that heat can be absorbed in all directions at high temperatures, and protecting the outer insulation layer 3 without any omissions.

[0027] Furthermore, the high-temperature resistant layer 4 is tightly attached to the outside of the outer insulation layer 3, which can immediately block heat and prevent the outer insulation layer 3 from being directly exposed to high temperatures. When encountering high temperatures, the micro-phase change capsules 432 and the elastic thermally conductive filler 42 in the high-temperature resistant layer 4 work together to quickly absorb heat and cool down, directly reducing the operating temperature of the outer insulation layer 3 and preventing its insulation performance from deteriorating and its mechanical strength from being lost. The shielding layer 5 is made of metal, which has good thermal conductivity. It covers the outside of the high-temperature resistant layer 4 without affecting the shielding effect, and at the same time, it prevents the shielding layer 5 from directly contacting the outer insulation layer 3, thus quickly transferring heat to the outer insulation layer 3. The outer insulation layer 3 is the point where the internal heat of the cable meets the external heat. The high-temperature resistant layer 4 is located between the outer insulation layer 3 and the shielding layer 5. This position can intercept heat in both directions. It can absorb the internal heat transferred from the outer insulation layer 3 to prevent heat accumulation and softening of the insulation. It can also block the high temperature transferred from the outside to prevent the insulation from being baked, thus improving the insulation performance. This solves the problem that ordinary halogen-free low-smoke cables have a low heat resistance limit. When the cable is in a high-temperature environment for a long time, the insulation layer is prone to softening, melting, deformation, or even cracking and damage, which leads to a decrease in insulation performance and problems such as leakage and short circuit. In severe cases, it can cause cable failure.

[0028] It should also be noted that the outer surfaces of the two sides of the shape memory polymer 438 are fixedly connected to the outer surfaces of one side of the two expansion plates 433 respectively. Under the expansion thrust of the shape memory polymer 438, the two expansion plates 433 are forced to move in opposite directions, and push the micro phase change capsule 432 to move towards the inner wall of the high temperature resistant layer 4 through the fixing rod 435 and the fixing plate 434.

[0029] See Figures 6-8 As shown, the shape memory polymer 438 is a halogen-free, low-smoke, flame-retardant shape memory polymer 438, which has the characteristics of halogen-free, low-smoke, and flame retardant properties, consistent with the overall environmental protection requirements of the cable. It can expand rapidly after being heated in the range of 70-100℃, with an expansion rate of 5%-10%. After the temperature drops to room temperature (or below the phase change temperature), it can automatically return to its initial shape. When the cable is subjected to high temperature, the heat absorption and cooling component 43 is passively triggered. The shape memory polymer 438 expands due to heat and is limited by the two sides of the fixing block 431, causing it to expand towards the two expansion plates 433. This pushes the two expansion plates 433, causing them to slide. The fixing rod 435, which is fixedly connected, pushes the fixing plates 434 on both sides to move, thereby pushing the micro phase change capsules 432 on both sides to move towards the inner walls of the high-temperature resistant base layer 41 and to fit tightly against the inner walls. This increases the contact area between the micro phase change capsules 432 and the inner walls of the high-temperature resistant base layer 41, reduces the contact gap, accelerates the heat transfer speed, triggers the heat absorption reaction, and quickly reduces the cable temperature, improving the cooling efficiency. In addition, under high temperature conditions, the layers of the cable will undergo slight deformation due to thermal expansion and contraction. The expansion action of the shape memory polymer 438 can adapt to this deformation. The expansion thrust drives the micro phase change capsules 432 to fit tightly against the inner wall of the high-temperature resistant base layer 41, preventing the micro phase change capsules 432 from separating from the inner wall due to the expansion of the high-temperature resistant base layer 41, and ensuring that the heat absorption and cooling function remains effective. When the shape memory polymer 438 returns to room temperature, it automatically restores its initial shape. At this time, the expansion thrust disappears, and the stretched conical spring 436 automatically rebounds, pulling the fixing plate 434 and the micro-phase change capsule 432 back to their original positions, adapting to the cold shrinkage and recovery of each layer of the cable.

[0030] It should also be noted that two guide rails 439 are fixedly installed at the top and bottom of the fixed block 431, and two grooves 4310 are opened at the top and bottom of the two expansion plates 433. The eight grooves 4310 are distributed in pairs of two grooves 4310 in each longitudinal direction, and the outer surfaces of the four guide rails 439 are respectively movably embedded in the interior of the four sets of grooves 4310.

[0031] See Figures 7-8 As shown, the top and bottom of the expansion plate 433 are fitted onto the guide slide 439 via the slide groove 4310. When the expansion plate 433 is subjected to expansion thrust, it is forced to slide outside the guide slide 439, which helps to reduce friction and allows the expansion plate 433 to move smoothly and stably.

[0032] It should also be noted that multiple movable holes 437 are provided on both outer surfaces of the fixing block 431, and the outer surface of each fixing rod 435 is movably embedded in the interior of the movable hole 437. The six conical springs 436 are arranged in groups of three vertically distributed.

[0033] See Figures 7-8 As shown, the movable hole 437 is provided to facilitate the movement of the fixing rod 435 outside the fixing block 431, thereby pushing the connected fixing piece 434 to move, and realizing the movement of the micro phase change capsule 432.

[0034] It should also be noted that one end of each of the two sets of conical springs 436 is fixedly connected to the outer surfaces of both sides of the fixing block 431, and the six fixing rods 435 distributed vertically form a group. One end of each of the two sets of fixing rods 435 is fixedly connected to the outer surface of the other side of the two extension plates 433.

[0035] See Figures 7-8 As shown, a conical spring 436 is provided to achieve an elastic connection between the fixed plate 434, the micro-phase change capsule 432 and the fixed block 431. When the expansion plate 433 moves, it pushes the fixed rod 435 to move, which in turn pushes the fixed plate 434 to move and pulls the conical spring 436 to unfold. When the pushing force on the expansion plate 433 disappears, the tension on the conical spring 436 disappears. The rebound force of the conical spring 436 can then be used to pull the fixed plate 434 and the micro-phase change capsule 432 to move in the opposite direction and reset.

[0036] It should also be noted that each connector 44 includes a first connecting block 441 and a second connecting block 442. One end of the first connecting block 441 is fixedly installed with an elastic ball 445, and one end of the second connecting block 442 is fixedly installed with an elastic ball sleeve 443. The outer surface of the elastic ball 445 is movably embedded inside the elastic ball sleeve 443. The outer surface of the elastic ball sleeve 443 has a locking hole 444. The outer surface of one end of the first connecting block 441 is movably embedded inside the locking hole 444. The outer surfaces of the first connecting block 441 and the second connecting block 442 are respectively fixedly installed on the outer surfaces of two adjacent fixing blocks 431.

[0037] See Figures 5-6As shown, the connectors 44 on both sides of the fixing block 431 are symmetrically arranged. The heat-absorbing and cooling components 43 with the second connector 442 installed are sequentially and intermittently inserted into the mounting groove 45. Then, the heat-absorbing and cooling components 43 with the first connector 441 installed are sequentially and intermittently inserted into the mounting groove 45. Simultaneously, the elastic retaining ball 445 is pressed and engaged into the elastic ball sleeve 443, with one end of the first connector 441 inserted into the retaining hole 444, thus completing the connection between two adjacent heat-absorbing and cooling components 43. The connectors 44 enable the connection of independent heat-absorbing and cooling components 43, thereby integrating multiple circumferentially distributed heat-absorbing and cooling components 43 into a single unit, improving the stability and overall strength of the heat-absorbing and cooling components 43, and enhancing the overall tensile strength of the cable.

[0038] It should also be noted that the outer surface of the elastic thermally conductive filler 42 is provided with multiple mounting grooves 45, and each heat-absorbing and cooling component 43 is embedded in the mounting groove 45. The outer surface of the elastic thermally conductive filler 42 is provided with multiple connecting grooves 46, and each connector 44 is embedded in the connecting groove 46.

[0039] See Figures 4-5 As shown, the mounting groove 45 is used to install the heat-absorbing and cooling component 43, supporting and limiting the heat-absorbing and cooling component 43 to prevent it from shifting and slipping during cable dragging, thus affecting the high-temperature resistance of the cable. The connecting groove 46 holds the mounting connector 44 to connect the heat-absorbing and cooling component 43, avoiding compression of the elastic thermally conductive filler 42.

[0040] It should also be noted that the outer surface of the high-temperature resistant layer 4 is provided with a shielding layer 5 for shielding against external electromagnetic interference. The outer surface of the shielding layer 5 is provided with an inner protective layer 6 for isolating mechanical damage and preventing the intrusion of water, oil, and impurities. The outer surface of the inner protective layer 6 is provided with an armor layer 7 for protecting the inner protective layer 6. The outer surface of the armor layer 7 is provided with an outer sheath layer 8 for protecting the internal structure of the cable.

[0041] See Figure 1As shown, multiple conductor cores 1 are arranged in parallel to form the core conductive unit of the cable. The filling layer 2 is made of halogen-free flame-retardant glass fiber rope with a diameter of 0.5-1.0mm. It has excellent high-temperature resistance, halogen-free and low-smoke characteristics, does not release halogen toxic gases when burning, and produces little smoke. It covers the outside of conductor core 1 to prevent the conductor core 1 from shifting. The outer insulation layer 3 covers the filled conductor core 1 to achieve overall insulation protection. The three work together to lay the foundation for the core conductivity and basic insulation of the cable, while ensuring the stability of the cable core structure and providing support for the function of subsequent functional layers. The outer insulation layer 3, as the overall insulation barrier of the cable core, isolates the internal conductor core 1 from the external structure and is a key node for heat exchange between the inside and outside. The high-temperature resistant layer 4 is tightly attached to the outer surface of the outer insulation layer 3. Through the triple action of phase change heat absorption by micro phase change capsule 432, heat homogenization by elastic thermally conductive filler 42, and heat release by decomposition of inorganic flame retardant, it intercepts heat bidirectionally and absorbs it inward. The outer insulation layer 3 absorbs internal heat transfer and blocks external high temperatures, directly reducing the operating temperature of the outer insulation layer 3. The shielding layer 5, made of metal, shields against external electromagnetic interference while also helping to dissipate heat from the high-temperature resistant layer 4. The three layers work together to protect the outer insulation layer 3 from multiple dimensions of heat insulation, heat absorption, heat dissipation, and heat transfer prevention, preventing it from softening and melting at high temperatures and ensuring insulation performance. The inner sheath 6 isolates the shielding layer 5 from the armor layer 7, preventing the armor layer 7 from causing mechanical damage to the shielding layer 5, while also preventing water and oil intrusion. The armor layer 7 enhances the cable's resistance to pressure, tension, and rodent bites, improving the mechanical protection level and adapting to complex environments. The outer sheath 8, as the outermost layer, resists external damage and protects the integrity of all internal structural layers. The three layers work in a progressive manner, from internal isolation and protection to middle-layer mechanical reinforcement and then to outer-layer environmental resistance, achieving all-dimensional structural protection and ensuring the structural stability of the cable under complex working conditions.

[0042] Furthermore, the insulation layer uses halogen-free rubber. First, the halogen-free rubber matrix is ​​mixed with inorganic flame retardants, high-temperature resistant additives, crosslinking agents, and anti-aging agents according to a specified ratio. This mixture is then internally mixed at 100-120℃ for 15-20 minutes to ensure the additives are evenly dispersed in the rubber matrix. After internal mixing, the mixture is rolled into a thin layer using a two-roll mill, with a thickness controlled at 2-3 mm to remove air bubbles and obtain a uniform insulating rubber compound. This compound is then allowed to stand for 8-12 hours to cure and eliminate internal stress. Next, the cured compound is pre-extruded into a tubular shape (adapted to the outer diameter of core 1 and filler layer 2) using an extruder. The extrusion temperature is controlled at 80-90℃ to ensure a uniform extruded rubber layer thickness, without material gaps or air bubbles. After extrusion... Immediately perform pre-crosslinking treatment using steam at 120℃ for 10-15 minutes to initially crosslink the rubber, improving the shape stability of the rubber layer and preventing deformation during subsequent processing. Then, lightly grind the outer surface of the pre-crosslinked rubber insulation layer to remove surface nodules and burrs, making the surface roughness uniform. Wipe the surface with a halogen-free cleaner to remove grinding debris and oil stains, and let it dry for later use. This lays the foundation for tight bonding with the outer layer structure (wrapping layer 103 and high-temperature resistant layer 4). Finally, conduct preliminary tests on the appearance, thickness, and insulation resistance of the pre-treated rubber insulation layer, and reject semi-finished products with appearance defects or excessive thickness deviations. Only after passing the inspection can the subsequent coating process begin.

[0043] It should also be noted that each core 1 includes a conductor 101. The outer surface of the conductor 101 is provided with an inner insulation layer 102 for electrical isolation of the conductor 101. The outer surface of the inner insulation layer 102 is provided with a wrapping layer 103 for protecting the inner insulation layer 102. The inner insulation layer 102 is made of halogen-free cross-linked polyethylene material and an inorganic flame retardant is added. The wrapping layer 103 is made of halogen-free flame retardant glass fiber tape and is wrapped around the outer surface of the inner insulation layer 102.

[0044] As shown in Figure 2, conductor 101 is made of tin-plated copper and is the core conductive unit of wire core 1. Inner insulation layer 102 directly wraps conductor 101, achieving electrical isolation between conductor 101 and the external structure. It is the first barrier for insulation of wire core 1. Inner insulation layer 102 uses halogen-free cross-linked polyethylene as the base material and adds aluminum hydroxide and magnesium hydroxide inorganic flame retardants. The amount of flame retardant added is 35%-55% of the base material mass. At the same time, 0.8%-2.5% antioxidant and 1.5%-3.5% lubricant are added to improve the heat resistance, processing performance and anti-aging performance of the material. The wrapping layer 103 is made of halogen-free flame-retardant non-woven fabric and wraps the inner insulation layer 102 to provide physical protection and prevent the inner insulation layer 102 from being worn and squeezed during cable laying and bending. It indirectly ensures the insulation integrity of the inner insulation layer 102. The two work together to form a double layer of insulation protection of electrical insulation and physical protection.

[0045] Please see Figures 1-9As shown, the overall effect and working principle of the mechanism are as follows: When the cable temperature rises to the phase change temperature of the microcapsule core 4322, the core material 4322 undergoes a phase change, changing from solid to liquid, passively absorbing a large amount of heat, achieving a rapid reduction in the internal temperature of the cable, and preventing the outer insulation layer 3 from softening and melting due to high temperature; the inorganic flame retardant added to the high-temperature resistant base layer 41 undergoes a decomposition reaction at high temperature, releasing water vapor, further absorbing heat, diluting combustible gases, and inhibiting the rise in cable temperature; the elastic thermally conductive filler 42 has high thermal conductivity, quickly and evenly conducting the high temperature transferred by the high-temperature resistant base layer 41 to all heat-absorbing and cooling components 43, shortening the heat transfer path; at the same time, the heat-absorbing and cooling components 43 are passively triggered, the shape memory polymer 438 expands due to heat, pushing the two extension plates 433 to slide, and pushing the fixing plate 434 and the micro-phase change capsule 432 to move through the fixing rod 435, so that the micro-phase change capsule 432 is tightly attached to the inner walls on both sides of the high-temperature resistant base layer 41, reducing the contact gap, accelerating the heat transfer speed, and improving the cooling efficiency. When the cable temperature drops below the phase change temperature, the core material 4322 returns to a solid state, enabling it to absorb heat and cool down again, forming a cyclic protection. Meanwhile, the shape memory polymer 438 automatically returns to its initial shape, and the stretched conical spring 436 automatically rebounds, pulling the fixing plate 434 and the micro-phase change capsule 432 back to their original positions. This improves the cable's high-temperature resistance and protects the outer insulation layer 3. The connector 44 allows for the connection of the independent heat-absorbing and cooling components 43, thus integrating multiple circumferentially distributed heat-absorbing and cooling components 43 into a single unit. This improves the stability and overall strength of the heat-absorbing and cooling components 43, enhancing the overall tensile strength of the cable. The outer insulation layer 3 is a critical node for heat exchange between the inside and outside. The high-temperature resistant layer 4 is tightly bonded to the outer surface of the outer insulation layer 3. Through the triple action of heat absorption by the micro-phase change capsule 432, heat homogenization by the elastic thermally conductive filler 42, and heat release by the decomposition of the inorganic flame retardant, heat is intercepted in both directions, directly reducing the operating temperature of the outer insulation layer 3. The shielding layer 5 is made of metal, which shields external electromagnetic interference while assisting in dissipating the heat of the high-temperature resistant layer 4. The three work together to protect the outer insulation layer 3 from multiple dimensions of heat insulation, heat absorption, heat dissipation, and heat transfer prevention, preventing it from softening and melting at high temperatures and ensuring insulation performance. The inner sheath 6 protects the shielding layer 5, the armor layer 7 enhances the cable's compressive and tensile strength, and the outer sheath layer 8 resists external damage. The three layers are progressively enhanced, from internal isolation and protection to middle layer mechanical reinforcement and then to outer layer environmental protection, achieving all-dimensional structural protection and ensuring the structural stability of the cable under complex working conditions. The wrapping layer 103 wraps the inner insulation layer 102, providing physical protection. The two work together to form a double-layer insulation guarantee of electrical insulation and physical protection.

[0046] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A high-temperature resistant halogen-free low-smoke wire and cable, comprising a plurality of cores (1), wherein the outer surface of the plurality of cores (1) is provided with a filling layer (2) for filling the gaps between the plurality of cores (1), and the outer surface of the filling layer (2) is provided with an outer insulation layer (3) for overall insulation protection of the cores (1), characterized in that: It also includes a high-temperature resistant layer (4), which is attached to the outer surface of the outer insulation layer (3) for bidirectional heat interception. The high-temperature resistant layer (4) includes a high-temperature resistant base layer (41), which is attached to the outside of the outer insulation layer (3). The heat-absorbing and cooling component (43) is provided in multiple ways. Each heat-absorbing and cooling component (43) includes a fixing block (431) and a shape memory polymer (438). Three micro phase change capsules (432) are equidistantly arranged on both outer surfaces of the fixing block (431) for passively triggering heat absorption and rapidly reducing the internal temperature of the cable. Two expansion plates (433) are movably embedded inside the fixing block (431). A fixing plate (434) is fixedly connected to the outer surface of each micro phase change capsule (432). Two fixing rods (435) are fixedly installed on the outer surface of each fixing plate (434). A conical spring (436) is fixedly connected to the center of the outer surface of each fixing plate (434). Connector (44), which is provided in multiple ways, is used to connect two adjacent heat-absorbing and cooling components (43). Each of the microphase change capsules (432) includes a capsule wall (4321) and a capsule core (4322) is disposed inside the capsule wall (4321), which is made of composite phase change material to accelerate the phase change reaction rate.

2. The high-temperature resistant halogen-free low-smoke wire and cable according to claim 1, characterized in that: The elastic thermally conductive filler (42) is filled inside the high-temperature resistant base layer (41) to provide flexible support for the heat-absorbing and cooling component (43) and to quickly and evenly transfer the heat transferred by the high-temperature resistant base layer (41) to the heat-absorbing and cooling component (43). The high-temperature resistant base layer (41) is made of halogen-free low-smoke flame-retardant polyolefin substrate and is mixed with inorganic flame retardants such as aluminum hydroxide and magnesium hydroxide.

3. The high-temperature resistant halogen-free low-smoke wire and cable according to claim 2, characterized in that: The outer surfaces of the two sides of the shape memory polymer (438) are fixedly connected to the outer surfaces of one side of the two expansion plates (433). Under the expansion thrust of the shape memory polymer (438), the two expansion plates (433) are forced to move in opposite directions and push the micro phase change capsule (432) to the inner wall of the high temperature resistant layer (4) through the fixing rod (435) and the fixing plate (434).

4. The high-temperature resistant halogen-free low-smoke wire and cable according to claim 3, characterized in that: Two guide rails (439) are fixedly installed at the top and bottom of the fixed block (431). Two grooves (4310) are opened at the top and bottom of the two expansion plates (433). The eight grooves (4310) are arranged in pairs of two grooves (4310) in each longitudinal direction. The outer surfaces of the four guide rails (439) are respectively movably embedded in the interior of the four sets of grooves (4310).

5. The high-temperature resistant halogen-free low-smoke wire and cable according to claim 4, characterized in that: The outer surfaces of both sides of the fixing block (431) are provided with multiple movable holes (437), and the outer surface of each fixing rod (435) is movably embedded in the movable hole (437). The six conical springs (436) are arranged in groups of three vertically distributed.

6. The high-temperature resistant halogen-free low-smoke wire and cable according to claim 5, characterized in that: One end of each of the two sets of conical springs (436) is fixedly connected to the outer surfaces of both sides of the fixing block (431). Each set of six fixing rods (435) is vertically distributed. One end of each of the two sets of fixing rods (435) is fixedly connected to the outer surface of the other side of the two extension plates (433).

7. The high-temperature resistant halogen-free low-smoke wire and cable according to claim 6, characterized in that: Each of the connectors (44) includes a first connecting block (441) and a second connecting block (442). One end of the first connecting block (441) is fixedly fitted with an elastic ball (445), and one end of the second connecting block (442) is fixedly fitted with an elastic ball sleeve (443). The outer surface of the elastic ball (445) is movably embedded inside the elastic ball sleeve (443). The outer surface of the elastic ball sleeve (443) is provided with a locking hole (444). One end of the outer surface of the first connecting block (441) is movably embedded inside the locking hole (444). The outer surfaces of the first connecting block (441) and the second connecting block (442) are respectively fixedly installed on the outer surfaces of two adjacent fixing blocks (431).

8. The high-temperature resistant halogen-free low-smoke wire and cable according to claim 7, characterized in that: The outer surface of the elastic thermally conductive filler (42) is provided with a plurality of mounting grooves (45), and each heat-absorbing and cooling component (43) is embedded in the mounting groove (45). The outer surface of the elastic thermally conductive filler (42) is provided with a plurality of connecting grooves (46), and each connecting component (44) is embedded in the connecting groove (46).

9. The high-temperature resistant halogen-free low-smoke wire and cable according to claim 8, characterized in that: The outer surface of the high-temperature resistant layer (4) is provided with a shielding layer (5) for shielding external electromagnetic interference. The outer surface of the shielding layer (5) is provided with an inner protective layer (6) for isolating mechanical damage and blocking the intrusion of water, oil and impurities. The outer surface of the inner protective layer (6) is provided with an armor layer (7) for protecting the inner protective layer (6). The outer surface of the armor layer (7) is provided with an outer sheath layer (8) for protecting the internal structure of the cable.

10. The high-temperature resistant halogen-free low-smoke wire and cable according to claim 9, characterized in that: Each of the cores (1) includes a conductor (101), the outer surface of which is provided with an inner insulation layer (102) for electrical isolation of the conductor (101), and the outer surface of the inner insulation layer (102) is provided with a wrapping layer (103) for protecting the inner insulation layer (102). The inner insulation layer (102) is made of halogen-free cross-linked polyethylene material and an inorganic flame retardant is added. The wrapping layer (103) is made of halogen-free flame retardant glass fiber tape and is wrapped around the outer surface of the inner insulation layer (102).

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