Moistureproof cable

Abstract

The invention relates to the technical field of power transmission, in particular to a moisture-proof cable which sequentially comprises a conductive wire core, a gradient buffer layer, a dynamic sealing layer, a flexible supporting layer and a self-repairing sheath from inside to outside. A gradient buffer layer; the dynamic sealing layer is of a split type sealing structure formed by an outer ring surface sealing lip and an inner ring surface static sealing belt, the outer ring surface sealing lip is formed by embedding a polytetrafluoroethylene fiber reinforcing layer in a silicone rubber matrix, and the surface of the outer ring surface sealing lip is coated with a humidity response type graphene coating; the flexible supporting layer is formed by spirally winding a nickel-titanium alloy belt, and bionic fish scales are welded to the surface of the nickel-titanium alloy belt; the self-repairing sheath is characterized in that a hexagonal honeycomb structure is molded on the outer layer, hydroxyl-terminated polysiloxane and a platinum catalyst are contained in an A-type microcapsule, and modified epoxy resin is contained in a B-type microcapsule. The moisture-proof cable shows excellent corrosion resistance, moisture resistance and self-repairing capability in a humid environment, and can maintain good performance when subjected to external physical impact.

Description

Technical Field

[0001] The invention relates to the technical field of power transmission, and in particular to a moisture-proof cable. Background Art

[0002] In modern power transmission systems, cables are the core carriers of energy and information, and their reliability is directly related to industrial production and people's livelihood security. However, in complex and changeable humid environments, the protection system of traditional cables faces severe challenges. For example, in cross-sea power supply projects in coastal areas, salt spray erosion and high humidity environments accelerate the hydrolysis and aging of the cable insulation layer, resulting in frequent partial discharge. Fault analysis of a large port power supply system showed that insulation breakdown accidents caused by cable moisture accounted for 42% of the total faults, causing a single power outage loss of more than 10 million yuan.

[0003] Existing moisture-proof technologies mostly use single-layer water-blocking structures, such as corrugated aluminum sheaths or super absorbent resin tapes, but they are prone to failure under dynamic stress and temperature alternation conditions. Taking a subway tunnel power supply system as an example, the micro-gaps at the cable joints caused by thermal expansion and contraction lead to an average annual water seepage rate of 3.2L / km. The mechanical stability of the water-blocking powder after expansion in water is insufficient, and it cannot form a long-term seal. Summary of the invention

[0004] In order to solve the technical problem that in dynamic scenarios, low-voltage cables cannot operate stably for a long time under complex working conditions such as frequent bending, twisting, stretching and compression, the present invention provides a moisture-proof cable.

[0005] The technical solution provided by the embodiment of the present invention is as follows:

[0006] A moisture-proof cable comprises, from inside to outside, a conductive core, a gradient buffer layer, a dynamic sealing layer, a flexible support layer and a self-repairing sheath, wherein:

[0007] The conductive wire core is composed of a plurality of tinned copper wires twisted together, the surface of the copper wires is electroplated with a tin-nickel alloy layer, and the outer surface of the conductive wire core is coated with a cross-linked polyethylene insulation layer, and the outer surface of the insulation layer is pressed with a spiral groove structure;

[0008] The gradient buffer layer includes, from the inside to the outside, a fluororubber microsphere honeycomb layer, a polyurethane elastomer V-shaped groove layer, and a polytetrafluoroethylene fiber woven mesh layer;

[0009] The dynamic sealing layer consists of a split sealing structure consisting of an outer ring sealing lip and an inner ring static sealing belt. The outer ring sealing lip is made of a silicone rubber matrix with a polytetrafluoroethylene fiber reinforcement layer embedded in it, and the surface is coated with a humidity-responsive graphene coating. The static sealing belt is made of fluororubber.

[0010] The flexible support layer is formed by spirally winding a nickel-titanium alloy belt, and a bionic fish scale is welded on the surface of the nickel-titanium alloy belt;

[0011] The self-repairing sheath has an outer molded hexagonal honeycomb structure, and two-component microcapsules are evenly distributed inside the sheath. In the two-component microcapsules, type A microcapsules contain terminal hydroxyl polysiloxane and platinum catalyst, and type B microcapsules contain modified epoxy resin.

[0012] Preferably, the outer annular sealing lip of the dynamic sealing layer includes a main sealing lip and an auxiliary sealing lip, a wave-shaped fold structure is arranged at the root of the main sealing lip, the auxiliary sealing lip forms an angle of 20°-40° with the main sealing lip, and a nano-scale hydrophobic texture is arranged on the surface;

[0013] The humidity-responsive graphene coating is compounded of graphene oxide and polydopamine in a weight ratio of 3:1, and has a volume expansion rate of greater than or equal to 15% when the relative humidity is greater than or equal to 85%;

[0014] The static sealing belt is embedded with a carbon nanotube bundle, the diameter of the carbon nanotube bundle is 4-6nm, the length is 50-80μm, and the volume accounts for 3%-5%.

[0015] Preferably, in the bionic fish scales of the flexible support layer, the size of a single scale is 1.8-2.2 mm×3.8-4.2 mm, and the surface of the scale is coated with an epoxy resin-polyphenylene sulfide composite coating;

[0016] The gaps between adjacent scales are filled with liquid gallium-indium-tin alloy, with a melting point range of -25°C to -15°C and a surface tension coefficient of 0.4-0.6N / m;

[0017] The surface of the nickel-titanium alloy strip is etched with a stress groove with a depth of 0.04-0.06 mm and a groove width of 0.08-0.12 mm.

[0018] Preferably, the polyurethane elastomer V-groove layer matrix material of the gradient buffer layer is thermoplastic polyurethane with a Shore hardness of 45-55HA, a tensile strength of ≥35MPa, and an elongation at break of ≥500%;

[0019] Silicon dioxide nanoparticles with a diameter of 50-100 nm are set at the bottom of the groove, with a filling rate of 5%-8%;

[0020] Carbon nanotube bundles are embedded inside the elastomer, with a diameter of 4-6nm, a length of 50-80μm, and a volume share of 3%-5%.

[0021] Preferably, in the hexagonal honeycomb structure of the self-repairing sheath, the honeycomb is filled with a silicone rubber composite material containing 0.5%-1.5% graphene, and the specific surface area of ​​the graphene is ≥500m 2 / g;

[0022] The microcapsule wall material is polyurethane-urea-formaldehyde resin copolymer, with a wall thickness of 2-5 μm;

[0023] The outer surface of the sheath is coated with a polytetrafluoroethylene wear-resistant layer.

[0024] Preferably, a semi-conductive shielding layer is arranged between the insulating layer of the conductive core and the gradient buffer layer, and the material thereof is a composite of ethylene-vinyl acetate copolymer and carbon black, with a carbon black content of 25%-35% and a volume resistivity of 10 3 -10 4 Ω·cm;

[0025] The outer surface of the semi-conductive shielding layer is pressed with a diamond grid structure with a depth of 0.05-0.1mm, a grid side length of 2-3mm, and the grid is filled with a silicone rubber composite material containing 1%-3% carbon nanotubes.

[0026] Preferably, the carbon black of the semi-conductive shielding layer is conductive carbon black with a particle size of 20-50 nm and a specific surface area of ​​≥800 m 2 / g;

[0027] Silicon dioxide reinforcement particles with a diameter of 0.1-0.2 mm are arranged at the corners of the diamond grid structure, and the surface of the particles is treated with a silane coupling agent.

[0028] Preferably, a stress monitoring layer is arranged outside the flexible supporting layer, and the stress monitoring layer includes:

[0029] Polyurethane-based elastomer substrate, Shore hardness 40-50HA;

[0030] Embed a fiber grating sensor array in the substrate, with a fiber diameter of 0.15-0.25 mm and a grating spacing of 50-100 mm;

[0031] Distributed strain detection module, sampling frequency ≥ 100Hz, strain resolution ≤ 1με.

[0032] Preferably, the optical fiber surface of the fiber grating sensor array is coated with a polytetrafluoroethylene protective layer;

[0033] 3%-5% of titanium dioxide nanoparticles with a particle size of 20-50nm are added to the polyurethane-based elastomer matrix.

[0034] Preferably, the hexagonal honeycomb structure of the self-repairing sheath is embedded with a micro piezoelectric energy collector, and the micro piezoelectric energy collector includes a lead zirconate titanate piezoelectric ceramic sheet, a flexible electrode layer and an energy storage unit:

[0035] The lead zirconate titanate piezoelectric ceramic sheet is located at the geometric center of the hexagonal honeycomb structure, and its upper and lower surfaces are directly in contact with the flexible electrode layer to form a double-sided electrode structure. The size of the lead zirconate titanate piezoelectric ceramic sheet is 1.0-1.5mm×1.0-1.5mm×0.05-0.1mm;

[0036] The flexible electrode layer is composed of a silver nanowire / graphene composite conductive film with a square resistance of ≤10Ω / □;

[0037] The energy storage unit includes a solid-state supercapacitor, which is integrated in the form of a thin film at the six vertices of the honeycomb unit. Each vertex is equipped with a capacitor, which is connected to the central electrode layer through a conductive path to form a parallel energy storage network with a capacity of 0.5-1.0mF / cm 2 .

[0038] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0039] 1. The present invention achieves excellent moisture resistance and mechanical reliability through a multi-layer composite structure. Its conductive core is made of multiple strands of tin-nickel alloy copper wires twisted together. The surface electroplating layer can achieve 500 hours of corrosion resistance after salt spray test. The spiral groove design increases the thermal conductivity by 20%. The cross-linked polyethylene insulation layer (XLPE) achieves a breakdown field strength of 30kV / mm through a cross-linked structure. After the spiral groove is pressed, the dielectric constant is reduced to 2.3 to suppress partial discharge.

[0040] 2. The gradient buffer layer of the present invention includes a triple collaborative design: the fluororubber microsphere honeycomb layer absorbs vibration energy through a porosity of 60-70%, the polyurethane V-groove layer is embedded with silica nanoparticles to reduce the wear rate by 50%, and the polytetrafluoroethylene woven mesh prevents interlayer adhesion with a friction coefficient of ≤0.1. The dynamic sealing layer innovatively adopts a main and auxiliary double lip structure. The 0.1-0.2mm wave folds of the main sealing lip and the 20°-40° angle of the auxiliary sealing lip form a pressure gradient, and the graphene oxide / polydopamine composite coating produces a 15% volume expansion when the humidity is ≥85% to achieve self-repair. The static sealing tape is embedded with 4-6nm carbon nanotube bundles to form a 10 3 Ω·cm conductive network, with electromagnetic shielding function.

[0041] 3. The flexible support layer of the present invention is spirally wound with nickel-titanium alloy, combined with a bionic fish scale structure, and the gap is filled with liquid gallium-indium-tin alloy to achieve a gap of ≤1×10 -6 Pa·m 3 / s leakage rate. The self-healing sheath is filled with graphene silicone rubber through a hexagonal honeycomb structure, with a compressive strength of ≥50MPa. The two-component microcapsule completes 90% repair within 30 seconds under a critical stress of 1-3MPa. The piezoelectric energy harvesting system uses a combination of lead zirconate titanate ceramics (500pC / N piezoelectric constant) and silver nanowire electrodes to achieve 10μW / cm 3 Energy density. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0043] Figure 1 A schematic cross-sectional view of a moisture-proof cable provided by an embodiment of the present invention;

[0044] Figure 2 A schematic diagram of a bionic fish scale of a moisture-proof cable provided by an embodiment of the present invention;

[0045] Figure 3 A schematic diagram of a self-repairing sheath of a moisture-proof cable provided in an embodiment of the present invention.

[0046] [reference numerals]

[0047] 1-conductive core, 11-insulating layer, 2-gradient buffer layer, 3-dynamic sealing layer, 31-outer annular sealing lip, 311-main sealing lip, 312-auxiliary sealing lip, 32-inner annular static sealing belt, 4-flexible supporting layer, 41-bionic fish scale, 5-self-repairing sheath, 51-two-component microcapsule.

[0048] As shown in the figure, in order to clearly implement the structure of the embodiment of the present invention, specific structures and devices are marked in the figure, but this is only for illustrative purposes and is not intended to limit the present invention to the specific structure, device and environment. According to specific needs, ordinary technicians in this field can adjust or modify these devices and environments. DETAILED DESCRIPTION

[0049] The technical solution of the present invention is described below in conjunction with the accompanying drawings. It is also noted that, in order to make the embodiments more detailed, the following embodiments are the best and preferred embodiments, and those skilled in the art may also adopt other alternatives to implement some known technologies; and the accompanying drawings are only for more specific description of the embodiments, and are not intended to specifically limit the present invention.

[0050] It should be noted that the references to "one embodiment", "an embodiment", "an exemplary embodiment", "some embodiments" and the like in the specification indicate that the embodiments described may include specific features, structures or characteristics, but not every embodiment may include the specific features, structures or characteristics. In addition, when a specific feature, structure or characteristic is described in conjunction with an embodiment, it should be within the knowledge of a person skilled in the art to implement such feature, structure or characteristic in conjunction with other embodiments (whether or not explicitly described).

[0051] In general, a term can be understood, at least in part, from its use in context. For example, depending, at least in part, on the context, the term "one or more" as used herein can be used to describe any feature, structure, or characteristic in the singular sense, or can be used to describe a combination of features, structures, or characteristics in the plural sense. Additionally, the term "based on" can be understood as not necessarily intended to convey an exclusive set of factors, but can instead, depending, at least in part, on the context, allow for the presence of other factors that are not necessarily explicitly described.

[0052] It will be understood that the meanings of “on,” “over,” and “above” in the present invention should be interpreted in the broadest manner, so that “on” not only means “directly on” something, but also includes the meaning of being “on” something with intervening features or layers therebetween, and “on” or “over” not only means “on” or “above” something, but also includes the meaning of being “on” or “above” something with no intervening features or layers therebetween.

[0053] Additionally, spatially relative terms such as "under," "beneath," "lower," "above," "upper," and the like may be used herein for descriptive convenience to describe the relationship of one element or feature to another element or features, as shown in the accompanying drawings. Spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the accompanying drawings. The device may be oriented in other ways, and the spatially relative descriptors used herein may be similarly interpreted accordingly.

[0054] like Figures 1 to 3 As shown, the embodiment of the present invention provides a moisture-proof cable, the design structure of which integrates a variety of advanced materials and technologies to improve the cable's resistance to moisture, mechanical damage and self-repairing capabilities. The connection and design methods at each level play an important role in protecting the cable's performance and extending its service life.

[0055] First, the conductive core is composed of multiple strands of tinned copper wires, and the surface of the copper wire is coated with a 5-8μm tin-nickel alloy layer. This design effectively prevents the oxidation of the copper wire in a humid environment, avoids the increase of contact resistance, and ensures the good conductivity of the cable. The twisting pitch is designed to be 10-15 times the diameter of the conductor, which makes the cable have higher mechanical flexibility and tensile resistance. The outer layer of the cross-linked polyethylene insulation layer further optimizes the cable's resistance to external forces through a spiral groove structure, reduces cable failures caused by partial discharge, and improves electrical safety.

[0056] On this basis, the design of the gradient buffer layer provides multiple protections in a progressive manner. The innermost layer is a fluororubber microsphere honeycomb layer. The design of the honeycomb aperture and microsphere diameter enables this layer to effectively absorb external mechanical vibrations and prevent the cable from being damaged by external forces. The outer polyurethane elastomer V-groove layer and the polytetrafluoroethylene fiber braided mesh layer form strong wear resistance and tensile strength through mutual cooperation, ensuring the durability of the cable in harsh environments. The polytetrafluoroethylene fiber braided mesh further enhances the tensile performance and tolerance to external friction.

[0057] The sealing structure composed of the dynamic sealing layer and the static sealing belt effectively prevents moisture penetration in humid environments. The sealing lip is made of a silicone rubber matrix with a polytetrafluoroethylene fiber reinforcement layer embedded in it, and coated with a humidity-responsive graphene coating to form a multi-layer waterproof protection. The humidity-responsive graphene coating can expand when the humidity is high, actively fill microcracks, prevent moisture intrusion, and significantly improve the moisture-proof performance of the cable.

[0058] The flexible support layer is made of spirally wound nickel-titanium alloy strips, and the surface is set in a bionic fish scale shape. The scale overlap rate in the structure is 25%-35%, which effectively delays the expansion of cracks and improves the tensile strength of the cable. The shape memory effect of nickel-titanium alloy ensures that the cable can return to its original shape when the external environment changes, enhancing its durability.

[0059] The self-repairing sheath adopts a hexagonal honeycomb structure, which can quickly recover when damaged by external forces to prevent further damage. The uniform distribution of the honeycomb and the embedded design of the microcapsules enable the cable to automatically repair itself after damage, especially after the microcapsules break, the polysiloxane and epoxy resin generated by the reaction will quickly fill the cracks to prevent moisture from penetrating or further damaging the insulation layer of the cable.

[0060] By combining materials and structures at all levels, this moisture-proof cable can achieve all-round protection for the cable, not only improving the cable's resistance to moisture, corrosion, abrasion and mechanical shock, but also enhancing the cable's long-term reliability through self-repair technology. This design enables the cable to work stably in extreme environments, prolongs its service life, reduces maintenance costs, and has important market value and application prospects.

[0061] In a possible implementation, by optimizing the structures of the dynamic sealing layer, the humidity-responsive graphene coating, and the static sealing tape, the protection performance of the cable in a humid environment is further enhanced, thereby improving the overall reliability of the cable.

[0062] First, the outer ring sealing lip of the dynamic sealing layer forms a more reliable waterproof sealing structure through the cooperation of the main sealing lip and the auxiliary sealing lip. The lip angle of the main sealing lip is 45°-60°. This design enables the sealing lip to form a closer contact when it comes into contact with external substances, preventing moisture from entering the cable. The wavy pleated structure at the root (pleat depth 0.1-0.2mm) can produce slight deformation when subjected to force, enhance the sealing effect, and restore its shape after multiple frictions or pressure changes, ensuring long-term sealing. The auxiliary sealing lip forms an angle of 20°-40° with the main sealing lip, further increasing the contact pressure of the sealing layer and enhancing the ability to resist external water seepage. In addition, the nano-scale hydrophobic texture set on the surface of the auxiliary sealing lip can effectively reduce the adhesion of water droplets and reduce the penetration of water, ensuring a more reliable sealing effect of the cable in a humid environment.

[0063] The humidity-responsive graphene coating is a composite of graphene oxide and polydopamine, with a coating thickness of 5-10μm. This coating can automatically respond to changes in humidity, and when the relative humidity reaches above 85%, the coating can expand by ≥15%. This expansion effect not only enhances the sealing ability of the graphene coating, but also effectively prevents further penetration of moisture, improving the stability of the cable in high humidity environments. The composite structure of graphene oxide and polydopamine gives the coating good humidity sensing ability, while improving the mechanical strength and durability of the coating, ensuring that it will not fail due to changes in external humidity conditions during long-term use.

[0064] The carbon nanotube bundles embedded in the static sealing tape improve the strength and durability of the sealing tape through their unique nanostructure. The diameter of the carbon nanotube bundle is 4-6nm, the length is 50-80μm, and the volume accounts for 3%-5%. The addition of these carbon nanotubes not only enhances the mechanical strength of the static sealing tape, but also improves the sealing and conductivity of the material through the nano effect, making the sealing tape more stable in long-term use and reducing aging and damage caused by temperature and humidity changes.

[0065] Through this multi-layer design, the moisture-proof cable achieves excellent moisture-proof, waterproof and anti-aging performance. The double sealing design of the dynamic sealing layer, the intelligent expansion characteristics of the humidity-responsive graphene coating and the reinforcement of the carbon nanotubes in the static sealing tape enable the cable to maintain good electrical performance and mechanical stability in extremely humid environments, greatly improving the service life and reliability of the cable.

[0066] In a possible implementation manner, this embodiment optimizes the structure, material selection and surface treatment of the flexible support layer to improve the mechanical strength, flexibility and fatigue resistance of the cable and enhance the reliability of the cable in complex environments.

[0067] First, the flexible support layer adopts a bionic fish scale shape, and the size of a single scale is designed to be 1.8-2.2mm×3.8-4.2mm. This structure not only has good self-locking performance, but also can evenly disperse stress under the action of external force to prevent local damage to the cable. The surface of the scale is coated with an epoxy resin-polyphenylene sulfide composite coating with a thickness of 20-30μm, which can enhance the wear resistance of the scale and improve its resistance to chemical corrosion. The selection of epoxy resin and polyphenylene sulfide composite materials provides strong physical strength and thermal stability, ensuring that the support layer is not easily deformed, aged or damaged during long-term use.

[0068] Furthermore, the liquid gallium indium tin alloy filled in the gaps between adjacent scales has a melting point range of -25°C to -15°C and a surface tension coefficient of 0.4-0.6N / m. The filling of this alloy not only effectively alleviates the friction between adjacent scales under the action of external forces, but also ensures adaptive adjustment when the temperature changes through its low melting point characteristics and moderate surface tension, further improving the toughness and impact resistance of the flexible support layer. In addition, the design of liquid alloy filling between scales helps to avoid mechanical damage caused by local overload, allowing the cable to maintain elasticity over a large range and adapt to changing working environments.

[0069] In addition, the stress groove etched on the surface of the nickel-titanium alloy strip has a depth of 0.04-0.06mm and a groove width of 0.08-0.12mm. The role of the etched groove is to reduce the stress concentration on the surface of the material and slow down the occurrence of metal fatigue. This design can effectively prevent the brittle fracture of the nickel-titanium alloy under the action of external force and enhance the long-term stability of the support layer. Nickel-titanium alloy has a strong shape memory effect and high elasticity, which enables the flexible support layer to return to its original shape after being stressed, avoiding permanent deformation of the cable, especially in an environment with large temperature fluctuations, it can still maintain excellent mechanical properties.

[0070] By combining the bionic fish scales with high-performance materials such as liquid gallium indium tin alloy and nickel titanium alloy, the flexible support layer of this moisture-proof cable has excellent flexibility, fatigue resistance and impact resistance. This design effectively improves the durability and adaptability of the cable, enabling it to withstand greater mechanical pressure, temperature fluctuations and wear and tear in long-term use in complex environments, significantly improving the service life and safety of the cable.

[0071] In a possible implementation, first, the base material of the gradient buffer layer is thermoplastic polyurethane (TPU), which has a Shore hardness of 45-55HA, a tensile strength of ≥35MPa, and an elongation at break of ≥500%. This material has good elasticity and tensile resistance, can effectively absorb and relieve external impact or tensile stress, and prevent the cable from breaking or deforming when subjected to stress. The selection of thermoplastic polyurethane enables the gradient buffer layer to maintain good flexibility during long-term use, while maintaining stable performance under different temperature environments.

[0072] Furthermore, the design of the V-shaped groove layer enables the buffer layer to better disperse external forces. Silica nanoparticles with a diameter of 50-100nm are embedded at the bottom of the groove, with a filling rate of 5%-8%. The addition of silica nanoparticles can improve the hardness and wear resistance of the buffer layer, while improving its bonding with other layers and enhancing the material's resistance to compression and friction. Due to the microscopic size of the nanoparticles, they can improve the mechanical properties of the material at the microscopic level and improve the overall stability of the buffer layer. In addition, the excellent thermal stability and weather resistance of silica can effectively resist chemical corrosion and high temperature in the external environment, further improving the durability of the cable.

[0073] In addition, the carbon nanotube bundles (tube diameter 4-6nm, length 50-80μm, volume proportion 3%-5%) embedded inside the elastomer further enhance the mechanical properties of the gradient buffer layer. Carbon nanotubes have very high strength and elastic modulus, which can significantly improve the compression, tensile and fatigue resistance of the buffer layer, while improving its electrical conductivity and thermal conductivity. When the cable is subjected to external force, the carbon nanotube bundles can effectively disperse the stress and prevent the cable from being damaged or aged due to frequent bending or stretching during use.

[0074] This design optimizes the performance of the gradient buffer layer by combining a composite material of thermoplastic polyurethane, silica nanoparticles and carbon nanotube bundles, thereby improving the service life and reliability of the cable in various complex environments. The buffer layer can effectively absorb and disperse external forces, resist the influence of the external environment, maintain the long-term stability of the cable, and enable the cable to maintain good mechanical properties and moisture resistance in a changing working environment.

[0075] In one possible embodiment, the design of the self-healing sheath significantly improves the durability, damage resistance and long-term stability of the cable by combining a hexagonal honeycomb structure, graphene reinforcements, microcapsule repair technology and a wear-resistant outer coating, especially having extremely high reliability in complex environments.

[0076] First, the hexagonal honeycomb structure as the core structure of the sheath not only provides good mechanical strength and compressive resistance, but also effectively disperses the pressure applied by the outside world. This honeycomb structure design makes the sheath have a high structural stability, which can ensure that other layers inside the cable are not affected when it is hit or bent by external forces, and avoid electrical failure of the cable due to external damage. At the same time, the silicone rubber composite material containing 0.5%-1.5% graphene filled in the honeycomb further enhances the flexibility and wear resistance of the sheath. The specific surface area of ​​​​graphene is ≥500m 2 / g, which means it has a larger surface area and stronger thermal conductivity, which can effectively improve the thermal conductivity and electrical properties of the sheath material, while enhancing the mechanical strength of the silicone rubber composite material, so that the sheath remains stable and flexible under high temperature or extreme environments.

[0077] Secondly, the application of microcapsule repair technology enables the cable to have self-repair capabilities. The wall material of the microcapsule is made of polyurethane-urea-formaldehyde resin copolymer, which has high rupture strength (≥5MPa) and temperature resistance. When the microcapsule is subjected to external mechanical damage, it will rupture and release repair materials to automatically fill the tiny cracks or damage on the surface of the sheath. The repair function can extend the service life of the cable and avoid serious damage caused by the expansion of small cracks. This self-repair mechanism enables the cable to quickly restore its structure when faced with external force damage, reducing maintenance costs and enhancing the long-term stability of the cable.

[0078] Finally, the outer surface of the sheath is coated with a polytetrafluoroethylene wear-resistant layer with a thickness of 10-20μm and a surface friction coefficient of ≤0.15. The polytetrafluoroethylene material has an extremely low friction coefficient and excellent wear resistance, which can effectively reduce the wear of the cable surface when it contacts with external objects, avoid damage caused by friction, and improve the cable's anti-pollution ability. In addition, the polytetrafluoroethylene wear-resistant layer also has excellent chemical stability, which can prevent acid and alkali corrosion and oil pollution, ensuring the long-term use of the cable in humid and harsh environments.

[0079] Combining the design of hexagonal honeycomb structure, graphene-enhanced silicone rubber composite material, microcapsule self-repairing technology and polytetrafluoroethylene wear-resistant layer, this moisture-proof cable has significant advantages, especially in improving the cable's damage resistance, repair ability and wear resistance. These designs enable the cable to maintain good performance and stability in the face of long-term use, external friction, temperature changes, chemical corrosion and physical damage, greatly improving the service life and reliability of the cable.

[0080] In a possible implementation, the addition of the semi-conductive shielding layer is to enhance the electromagnetic shielding performance of the cable and further improve the stability and anti-interference ability of the cable in complex environments. Specifically, the semi-conductive shielding layer is composed of a composite material of ethylene-vinyl acetate copolymer and carbon black, and the diamond grid structure and the embedding of carbon nanotubes are used to effectively suppress electromagnetic interference, thereby enhancing the overall performance of the cable.

[0081] First, the selection of the ethylene-vinyl acetate copolymer and carbon black composite material enables the semiconductive shielding layer to have appropriate conductive properties. The carbon black content is 25%-35%, and its volume resistivity is 10 3 -10 4 Ω·cm, this range of resistivity can ensure that the shielding layer has good conductivity, can effectively absorb and shield external electromagnetic waves, and will not affect the current signal inside the cable, thereby achieving the effect of electromagnetic interference (EMI) shielding. By reasonably controlling the proportion of carbon black, the electrical performance of the cable can be optimized to ensure the stability and anti-interference of signal transmission.

[0082] In addition, the outer surface of the semi-conductive shielding layer is pressed with a diamond grid structure (grid side length 2-3mm, pressing depth 0.05-0.1mm) to further enhance the mechanical strength of the shielding layer and make its surface have better heat dissipation performance. The grid structure can effectively increase the surface area of ​​the shielding layer and increase its contact area with the external environment, thereby increasing the shielding effect of electromagnetic waves. This structural design can also effectively disperse external impact forces, reduce damage to the cable caused by external forces, and protect the internal structure from physical damage.

[0083] Finally, the silicone rubber composite material filled with 1%-3% carbon nanotubes in the grid not only further enhances the electromagnetic shielding effect, but also improves the flexibility and fatigue resistance of the material. The embedding of carbon nanotubes improves the mechanical strength and conductivity of the composite material, making the shielding layer not only more efficient electrically, but also more wear-resistant and weather-resistant. The flexibility of the silicone rubber itself makes the shielding layer have a certain elasticity, which can adapt to the bending and stretching of the cable during installation or use, and avoid cracks or damage caused by external stress.

[0084] The semi-conductive shielding layer has multiple beneficial effects in moisture-proof cables through reasonable material selection and structural design. It can not only effectively shield electromagnetic interference and improve the signal transmission quality of the cable, but also enhance the mechanical strength and resistance to external damage of the cable, ensuring the stability and durability of the cable in long-term use. This design enables the cable to maintain good working performance in high interference, high temperature or harsh environment, ensuring the long-term reliable operation of the equipment.

[0085] In one possible implementation, the design of its semi-conductive shielding layer further optimizes the electrical performance and mechanical strength of the cable. By using a specific type of conductive carbon black and adding silica reinforcing particles at the corners of the mesh structure, the electromagnetic shielding effect, mechanical durability and ability to resist external impact of the cable are significantly improved.

[0086] First of all, the selection of conductive carbon black is crucial to improving the electrical performance of the semi-conductive shielding layer. 2 / g of conductive carbon black can significantly improve the conductivity and shielding performance of carbon black. Due to its small particle size and large specific surface area, conductive carbon black can form a more uniform conductive network in the semi-conductive shielding layer, enhance its conductivity, and make the cable have better electromagnetic interference (EMI) shielding effect. This kind of carbon black can effectively block external electromagnetic waves while maintaining stable transmission of signals inside the cable, avoiding the signal from being affected by external electromagnetic interference, especially in the process of high-frequency signal transmission.

[0087] Secondly, the design of setting silica reinforcing particles at the corners of the diamond grid structure further enhances the mechanical strength and wear resistance of the shielding layer. The corners are the parts of the grid structure that are most susceptible to stress concentration and external damage. Therefore, by adding silica reinforcing particles with a diameter of 0.1-0.2mm at the corners, the external forces can be effectively dispersed to avoid rupture or damage caused by excessive local stress. In addition, the surface of the silica particles is treated with a silane coupling agent to form a stronger interface bonding force between the particles and the surrounding composite material, thereby improving the bonding force and durability between the reinforcing particles and the shielding layer matrix. This surface treatment can improve the dispersibility of the particles and make them evenly distributed in the composite material, thereby optimizing the mechanical properties and anti-aging ability of the cable.

[0088] Through this design, the moisture-proof cable not only performs better in electrical shielding effect, but also can better resist external mechanical impact, friction and chemical corrosion during actual use, ensuring that the cable can maintain long-term stable operation in high temperature, high humidity or other extreme environments.

[0089] The design improves the electromagnetic shielding effect of the semi-conductive shielding layer by optimizing the selection and particle size control of conductive carbon black, and at the same time, by adding silica reinforcing particles at the corners of the grid structure and treating them with silane coupling agents, the mechanical strength and damage resistance of the cable are enhanced. These innovative measures not only improve the overall performance of the cable, but also greatly extend its service life and stability, especially in high-interference environments and extreme physical conditions.

[0090] In one possible implementation, a stress monitoring layer is added to the outside of the flexible support layer, which has a significant intelligent monitoring function. This design integrates a fiber grating sensor array and a distributed strain detection module, so that the cable can monitor stress changes in real time during use, thereby providing dynamic monitoring of the cable's working status and improving the reliability and safety of the cable in harsh environments.

[0091] First, the choice of polyurethane-based elastomer substrate gives the stress monitoring layer excellent elasticity and durability. Polyurethane-based elastomer materials have excellent wear resistance, weather resistance and aging resistance, and their Shore hardness is between 40-50HA, ensuring that they have a certain degree of flexibility and can effectively absorb and disperse external mechanical stress. This substrate can not only protect the fiber Bragg grating sensor from external physical damage, but also provide sufficient mechanical support to ensure the normal operation of the fiber Bragg grating.

[0092] Secondly, the fiber grating sensor array embedded in the substrate is the core component of the stress monitoring layer. The fiber grating sensor can measure strain with high precision by sensing the wavelength changes caused by small deformations of the optical fiber. The diameter of these optical fibers is 0.15-0.25mm, which can adapt to the bending and deformation of the cable, ensuring that the sensor can still work stably when the cable is subjected to external forces. The grating spacing is 50-100mm, which can cover the long-distance strain monitoring of the cable and provide sufficient spatial resolution to detect local strain changes inside the cable.

[0093] Finally, the addition of the distributed strain detection module makes the entire monitoring system more intelligent. The module has a high-precision detection capability with a sampling frequency of ≥100Hz and a strain resolution of ≤1με. It can monitor the strain of the cable in real time, especially under high load, frequent bending or stretching, and can detect any abnormal strain changes in time. Through real-time monitoring of cable stress, an early warning can be issued when the cable may be damaged or over-strained, preventing potential safety hazards in advance, thereby reducing the risk of cable failure and extending the service life of the cable.

[0094] The design of the stress monitoring layer integrates fiber grating sensors and strain detection modules in the cable, which not only provides real-time monitoring of the strain during cable use, but also prevents the cable from being damaged due to excessive stress through early warning. This design improves the safety and reliability of the cable, and is especially suitable for cables that need to run for a long time and are exposed to complex environments, such as submarine cables and long-distance power transmission lines. Through this intelligent monitoring technology, cable fault detection and maintenance work become more efficient, effectively reducing maintenance costs and improving equipment operation efficiency.

[0095] In one possible implementation, the protection of the fiber Bragg grating sensor, the performance of the substrate, and the accuracy of temperature compensation are further optimized. These innovative designs significantly improve the overall performance of the cable, especially in terms of high-precision stress monitoring and environmental adaptability.

[0096] First, the optical fiber surface of the fiber Bragg grating sensor array is coated with a polytetrafluoroethylene protective layer (thickness of 0.5-1.0μm). This design is to improve the durability and resistance to environmental interference of the fiber Bragg grating sensor. Polytetrafluoroethylene (PTFE) is a material that is very corrosion-resistant, high-temperature-resistant and has good insulation properties. Coating it on the surface of the optical fiber can effectively prevent moisture, chemicals, oxides and other corrosive substances from damaging the optical fiber. This protective layer not only extends the service life of the optical fiber, but also ensures the stable operation of the fiber Bragg grating in harsh environments, allowing the cable to provide accurate strain data under more complex working conditions.

[0097] Secondly, 2%-5% titanium dioxide nanoparticles with a particle size of 20-50nm are added to the polyurethane-based elastomer matrix. This improvement is to improve the mechanical properties and thermal stability of the matrix. Titanium dioxide nanoparticles play a reinforcing role in the polyurethane matrix, which not only improves the strength, hardness and wear resistance of the matrix, but also effectively improves the cable's UV resistance and anti-aging properties. When the cable is affected by external mechanical stress or environmental changes, the addition of titanium dioxide nanoparticles enables the matrix to provide better support and protection, thereby ensuring that the fiber grating sensor is not affected by external factors during the monitoring process and maintains a high degree of reliability.

[0098] Finally, the design of the temperature compensation unit uses a platinum resistance temperature sensor, which has a temperature measurement accuracy of ±0.1°C. Temperature changes will interfere with the measurement results of the fiber Bragg grating sensor. Therefore, the addition of the temperature compensation unit can effectively eliminate the influence of temperature on the strain data and ensure that temperature changes will not cause distortion of the monitoring data. The platinum resistance temperature sensor has high precision and stability, can monitor the ambient temperature around the cable in real time, and compensate by combining with the data of the fiber Bragg grating sensor, thereby improving the accuracy and consistency of strain measurement.

[0099] The fiber Bragg grating sensor array is embedded in a polyurethane-based elastomer substrate, the fiber surface is coated with a polytetrafluoroethylene protective layer to increase its durability, and titanium dioxide nanoparticles are added to the substrate to enhance its mechanical properties and thermal stability. The temperature compensation unit works together with the fiber Bragg grating sensor to improve the accuracy of the strain data.

[0100] Through this design, moisture-proof cables not only have stronger mechanical and environmental adaptability, but can also accurately monitor strain changes and effectively avoid errors caused by temperature changes. In this way, the cable can provide more reliable monitoring data in complex environments and is suitable for high-demand application scenarios, such as marine cables, remote communications and other engineering fields with high precision requirements.

[0101] In one possible implementation, by embedding a micro piezoelectric energy harvester in the hexagonal honeycomb structure of the self-healing sheath, the cable is given the ability to self-collect and store energy, thereby improving the energy self-sufficiency of the cable and extending its service life. This design provides a continuous power supply solution for the cable, which is particularly suitable for application environments where it is difficult to connect to an external power source, such as remote monitoring systems, drones and other automated equipment.

[0102] Lead zirconate titanate piezoelectric ceramic sheets are the core components of piezoelectric energy harvesters, and their size is 1.0-1.5mm×1.0-1.5mm×0.05-0.1mm. The piezoelectric ceramic sheets have good piezoelectric properties and can convert mechanical energy into electrical energy when subjected to external forces (such as cable bending, vibration or pressure). Its tiny size allows the piezoelectric ceramic sheets to be easily embedded in the honeycomb structure of the cable, which does not increase the volume of the cable while effectively collecting mechanical energy from the external environment. In this way, the cable can convert environmental energy into electrical power in real time when subjected to vibration or external forces, supporting the normal operation of other electronic components in the cable.

[0103] The flexible electrode layer is composed of a silver nanowire / graphene composite conductive film with a square resistance of ≤10Ω / □ and excellent conductivity and flexibility. The silver nanowire and graphene composite material can effectively reduce the resistance of the electrode, improve the current transmission efficiency, and ensure that the electrode layer will not fail due to deformation when the cable is bent or stressed. In addition, the flexible electrode layer can also be closely combined with the piezoelectric ceramic sheet, acting as a bridge between the voltage output and current collection generated by the piezoelectric effect, ensuring efficient energy conversion and transmission.

[0104] The energy storage unit uses a solid-state supercapacitor with a capacity of 0.5-1.0mF / cm 2 Supercapacitors can quickly store the electrical energy collected from piezoelectric ceramics and release it when needed. This design allows the cable to store energy through capacitors when the collected energy is not enough to directly drive the load, and then supply the system when the power is sufficient, thus ensuring that the cable can maintain a long-term energy supply.

[0105] The piezoelectric ceramic sheet converts external mechanical energy into electrical energy, which is transmitted to the energy storage unit (solid-state supercapacitor) through the silver nanowire / graphene composite conductive film, so that the cable can be self-powered. By embedding the piezoelectric energy collector in the hexagonal honeycomb structure, not only can the energy self-sufficiency of the cable be improved, but also the overall structural strength and durability of the cable can be improved. The design of the hexagonal honeycomb structure can provide additional mechanical support, so that the energy collector can still work stably when the cable is stressed, and will not fail due to the external environment or cable deformation.

[0106] This design can improve the functionality and reliability of the cable, and is particularly suitable for complex environments that require long-term, maintenance-free operation, such as smart cities, automated monitoring systems, and other fields.

[0107] The present invention covers any substitution, modification, equivalent method and scheme made on the essence and scope of the present invention. In order to make the public have a thorough understanding of the present invention, specific details are described in detail in the preferred embodiments of the present invention, but those skilled in the art can fully understand the present invention without the description of these details. In addition, in order to avoid unnecessary confusion about the essence of the present invention, well-known methods, processes, procedures, components and circuits are not described in detail.

[0108] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A moisture-proof cable, characterized in that: From the inside to the outside, it includes a conductive core, a gradient buffer layer, a dynamic sealing layer, a flexible support layer and a self-repairing sheath, wherein: The conductive wire core is composed of a plurality of tinned copper wires twisted together, the surface of the copper wires is electroplated with a tin-nickel alloy layer, and the outer surface of the conductive wire core is coated with a cross-linked polyethylene insulation layer, and the outer surface of the insulation layer is pressed with a spiral groove structure; The gradient buffer layer includes, from the inside to the outside, a fluororubber microsphere honeycomb layer, a polyurethane elastomer V-shaped groove layer, and a polytetrafluoroethylene fiber woven mesh layer; The dynamic sealing layer consists of a split sealing structure consisting of an outer ring sealing lip and an inner ring static sealing belt. The outer ring sealing lip is made of a silicone rubber matrix with a polytetrafluoroethylene fiber reinforcement layer embedded in it, and the surface is coated with a humidity-responsive graphene coating. The static sealing belt is made of fluororubber. The flexible support layer is formed by spirally winding a nickel-titanium alloy belt, and a bionic fish scale is welded on the surface of the nickel-titanium alloy belt; The self-repairing sheath has an outer molded hexagonal honeycomb structure, and two-component microcapsules are evenly distributed inside the sheath. In the two-component microcapsules, type A microcapsules contain terminal hydroxyl polysiloxane and platinum catalyst, and type B microcapsules contain modified epoxy resin.

2. A moisture-proof cable according to claim 1, characterized in that: The outer annular sealing lip of the dynamic sealing layer includes a main sealing lip and an auxiliary sealing lip. The root of the main sealing lip is provided with a wavy fold structure. The auxiliary sealing lip forms an angle of 20°-40° with the main sealing lip, and a nano-scale hydrophobic texture is provided on the surface. The humidity-responsive graphene coating is compounded of graphene oxide and polydopamine in a weight ratio of 3:1, and has a volume expansion rate of greater than or equal to 15% when the relative humidity is greater than or equal to 85%; The static sealing belt is embedded with a carbon nanotube bundle, the diameter of the carbon nanotube bundle is 4-6nm, the length is 50-80μm, and the volume accounts for 3%-5%.

3. A moisture-proof cable according to claim 2, characterized in that: In the bionic fish scales of the flexible support layer, the size of a single scale is 1.8-2.2 mm×3.8-4.2 mm, and the surface of the scale is coated with an epoxy resin-polyphenylene sulfide composite coating; The gaps between adjacent scales are filled with liquid gallium-indium-tin alloy, with a melting point range of -25°C to -15°C and a surface tension coefficient of 0.4-0.6N / m; The surface of the nickel-titanium alloy strip is etched with a stress groove with a depth of 0.04-0.06 mm and a groove width of 0.08-0.12 mm.

4. A moisture-proof cable according to claim 3, characterized in that: The polyurethane elastomer V-groove layer matrix material of the gradient buffer layer is thermoplastic polyurethane with a Shore hardness of 45-55HA, a tensile strength of ≥35MPa, and an elongation at break of ≥500%; Silicon dioxide nanoparticles with a diameter of 50-100 nm are set at the bottom of the groove, with a filling rate of 5%-8%; Carbon nanotube bundles are embedded inside the elastomer, with a diameter of 4-6nm, a length of 50-80μm, and a volume share of 3%-5%.

5. A moisture-proof cable according to claim 4, characterized in that: In the hexagonal honeycomb structure of the self-repairing sheath, the honeycomb is filled with a silicone rubber composite material containing 0.5%-1.5% graphene, and the specific surface area of ​​the graphene is ≥500m 2 / g; The microcapsule wall material is polyurethane-urea-formaldehyde resin copolymer, with a wall thickness of 2-5 μm; The outer surface of the sheath is coated with a polytetrafluoroethylene wear-resistant layer.

6. A moisture-proof cable according to any one of claims 1 to 5, characterized in that: A semi-conductive shielding layer is arranged between the insulating layer of the conductive core and the gradient buffer layer, and the material thereof is a composite of ethylene-vinyl acetate copolymer and carbon black, with a carbon black content of 25%-35% and a volume resistivity of 10 3 -10 4 Ω·cm; The outer surface of the semi-conductive shielding layer is pressed with a diamond grid structure with a depth of 0.05-0.1mm, a grid side length of 2-3mm, and the grid is filled with a silicone rubber composite material containing 1%-3% carbon nanotubes.

7. A moisture-proof cable according to claim 6, characterized in that: The carbon black of the semi-conductive shielding layer is conductive carbon black with a particle size of 20-50nm and a specific surface area of ​​≥800m 2 / g; Silicon dioxide reinforcement particles with a diameter of 0.1-0.2 mm are arranged at the corners of the diamond grid structure, and the surface of the particles is treated with a silane coupling agent.

8. A moisture-proof cable according to any one of claim 7, characterized in that: A stress monitoring layer is arranged outside the flexible supporting layer, and the stress monitoring layer includes: Polyurethane-based elastomer substrate, Shore hardness 40-50HA; Embed a fiber grating sensor array in the substrate, with a fiber diameter of 0.15-0.25 mm and a grating spacing of 50-100 mm; Distributed strain detection module, sampling frequency ≥ 100Hz, strain resolution ≤ 1με.

9. A moisture-proof cable according to claim 8, characterized in that: The optical fiber surface of the fiber grating sensor array is coated with a polytetrafluoroethylene protective layer; 3%-5% of titanium dioxide nanoparticles with a particle size of 20-50nm are added to the polyurethane-based elastomer matrix.

10. A moisture-proof cable according to claim 9, characterized in that: The hexagonal honeycomb structure of the self-repairing sheath is embedded with a micro piezoelectric energy collector, which includes a lead zirconate titanate piezoelectric ceramic sheet, a flexible electrode layer and an energy storage unit: The lead zirconate titanate piezoelectric ceramic sheet is located at the geometric center of the hexagonal honeycomb structure, and its upper and lower surfaces are directly in contact with the flexible electrode layer to form a double-sided electrode structure. The size of the lead zirconate titanate piezoelectric ceramic sheet is 1.0-1.5mm×1.0-1.5mm×0.05-0.1mm; The flexible electrode layer is composed of a silver nanowire / graphene composite conductive film with a square resistance of ≤10Ω / □; The energy storage unit includes a solid-state supercapacitor, which is integrated in the form of a thin film at the six vertices of the honeycomb unit. Each vertex is equipped with a capacitor, which is connected to the central electrode layer through a conductive path to form a parallel energy storage network with a capacity of 0.5-1.0mF / cm 2 .

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