Equipotential shielding fabric based on universal conductive composite yarn and method for manufacturing the same

Abstract

The application provides an equipotential shielding fabric based on a general conductive composite yarn and a preparation method thereof, and belongs to the technical field of electromagnetic radiation shielding, and aims to solve the problem that the existing live working shielding fabric adopts a secondary attaching process to add conductive fibers, which is easy to be hooked, broken and fallen off, and has poor shielding stability. In the application, the metal conductive fiber with a weight ratio of not less than 15% and the elastic base fiber are pretreated through an anti-oxidation coating and a twisting plying process, and then are synchronously and integrally mixed by a multi-channel knitting equipment, so that the metal conductive fiber is embedded in the loop structure of the elastic base fiber, and an integrally formed fabric without a splicing seam is formed. The method realizes a full-domain continuous low-resistance conductive path, and the direct current resistance can be stably reached to 1Ω~5.5Ω, so that the risk of hooking, breaking and falling off caused by the conductive wire floating on the surface is fundamentally avoided, and the equipotential shielding effect with the functions of flame retardation, high elasticity, adhesion and long-term stability is achieved.

Description

Technical Field

[0001] This invention belongs to the field of electromagnetic radiation shielding technology, specifically relating to an equipotential shielding fabric based on universal conductive composite yarn and its preparation method. Background Technology

[0002] Live-line working shielding fabric is a key protective equipment in scenarios such as high-voltage transmission line maintenance and substation operation and maintenance. Its core function is to bring the human body into an equipotential system through a continuous conductive network, thereby shielding the human body from the harm of power frequency electric fields.

[0003] Currently, most shielding gloves and fabrics in the industry employ a process where, after the base fabric is woven, conductive silver wires or fibers are attached to the fabric surface as floats via a subsequent manual hook-stitching process. While this process achieves basic conductive connectivity, the conductive wires are completely exposed on the fabric surface. Under repeated bending, friction, wearing and pulling, and in daily working environments, they are highly susceptible to snagging, breakage, and detachment, leading to localized disruptions in the conductive network. This results in a rapid decline in shielding performance over time, posing serious safety hazards. Furthermore, the subsequent hook-stitching process is a secondary, additional step, inevitably creating needle holes and localized stress concentration points on the fabric surface. This not only compromises the structural integrity of the fabric itself but also makes it difficult to ensure uniform coverage of the conductive wires across the entire stress-bearing area of ​​the palm and fingers, easily creating shielding blind spots. Although some low-voltage antistatic glove technologies attempt to embed a low proportion of flexible carbon fiber conductive filaments during the weaving process, the proportion of conductive fibers is typically only two to four percent. Furthermore, carbon fiber itself is flexible, and its material properties, conductivity mechanism, and process requirements differ fundamentally from the rigid metal conductive fibers required for high-voltage live-line work scenarios. Therefore, this type of technology does not solve the problems of filament breakage, oxidation, and tension mismatch when a high proportion of rigid metal conductive fibers directly participates in high-speed knitting, nor does it address the low-resistance, high-stability equipotential shielding requirements of shielding clothing systems. There has long been a technological bias in the existing technology, namely that conductive metal fibers such as silver, stainless steel, copper, and iron, due to their brittleness, easy oxidation and blackening, and significant modulus differences compared to aramid and elastic yarns, cannot be directly used as the main yarn in knitting at a high proportion of more than 15%. Otherwise, it would inevitably lead to frequent filament breakage, stiff fabrics, loss of elasticity, and inability to mass-produce. Therefore, the industry has consistently avoided moving the metal conductive function forward to the weaving process, relying instead on the compromise of subsequent stitching.

[0004] Therefore, there is an urgent need to develop a shielding fabric that can introduce conductive fibers during the weaving process of the base fabric. Summary of the Invention

[0005] This application provides an equipotential shielding fabric based on general conductive composite yarn and its preparation method, aiming to solve the problems of existing live-line work shielding fabrics that use a secondary additional process to add conductive fibers, which are prone to snagging, breaking, and falling off, resulting in poor shielding stability.

[0006] To solve the above problems, the technical solution adopted in this application is as follows: In the first aspect, this application proposes an equipotential shielding fabric based on universal conductive composite yarn, which is a one-piece molded structure without splicing seams, formed by synchronously and integrally weaving multiple heterogeneous yarns through a multi-channel knitting device; the multiple heterogeneous yarns include metal conductive fibers and elastic matrix fibers, the weight ratio of the metal conductive fibers is not less than 15%, and the metal conductive fibers are embedded in the coil structure of the elastic matrix fibers to form a continuous conductive path throughout the fabric.

[0007] Furthermore, the conductive metal fiber includes at least one of silver fiber, stainless steel fiber, copper fiber, and iron fiber.

[0008] Furthermore, the elastic matrix fiber is an aramid flame-retardant and high-temperature resistant fiber.

[0009] Furthermore, the multi-path heterogeneous yarn also includes elastic yarn, which includes at least one of spandex elastic yarn and elastic core-spun elastic yarn.

[0010] Furthermore, by weight percentage, the conductive metal fiber accounts for 15% to 25%, the elastic matrix fiber accounts for 65% to 80%, and the elastic yarn accounts for 3% to 10%.

[0011] Furthermore, the surface of the metal conductive fiber is provided with an anti-oxidation protective coating.

[0012] Furthermore, the conductive metal fiber and the elastic matrix fiber are twisted together and then fed into the multi-channel knitting equipment.

[0013] Furthermore, when the fabric has a cuff area, the cuff area of ​​the fabric is woven with high-elasticity yarn by automatically switching the yarn ratio to form a dense rib closure.

[0014] Furthermore, the metal conductive fiber is embedded within the coil structure of the elastic matrix fiber during the weaving stage.

[0015] Furthermore, the DC resistance is 1Ω to 5.5Ω.

[0016] Secondly, this application also proposes a shielding glove composed of the equipotential shielding fabric described in the first aspect, including a palm and finger body area and a wrist area. The glove is formed by synchronously and integrally blending multiple heterogeneous yarns through a multi-channel knitting device. The multiple heterogeneous yarns include metal conductive fibers and elastic matrix fibers. The weight percentage of the metal conductive fibers is not less than 15%, and the metal conductive fibers are embedded in the glove fabric structure and interwoven with the elastic matrix fibers to form a continuous conductive path throughout the entire area. The glove is integrally formed without splicing seams from the fingertips to the wrist.

[0017] Furthermore, the wrist opening area has a densely ribbed closure; a conductive lining connecting strip is provided on the outer side of the wrist opening area, the conductive lining connecting strip has a built-in metal lead, and the end of the metal lead is crimped with a conductive terminal.

[0018] Thirdly, this application also proposes a method for preparing the equipotential shielding fabric based on universal conductive composite yarn as described in the first aspect, comprising the following steps: Step 1: Pre-treating the metal conductive fiber and the elastic matrix fiber to form an anti-oxidation protective layer on the surface of the metal conductive fiber, and / or twisting the metal conductive fiber and the elastic matrix fiber together; Step 2: Simultaneously feeding the treated metal conductive fiber, the elastic matrix fiber, and the elastic yarn as multiple heterogeneous yarns into a multi-channel knitting device, controlling the feeding tension of each yarn to keep the tension difference between the metal conductive fiber and the elastic matrix fiber within a preset process tolerance range; Step 3: Embedding the metal conductive fiber inside the coil structure of the elastic matrix fiber through integrated blending to form a continuous conductive path throughout, resulting in a seamless integrally formed fabric; Step 4: Performing low-temperature relaxation hot air setting on the fabric, with the setting temperature not exceeding 80°C.

[0019] Furthermore, in step 3, when the fabric has a cuff area, the elastic core-spun yarn is automatically fed into the cuff area to form a dense rib closure.

[0020] One or more technical solutions proposed in this application have at least the following technical effects: Metal conductive fibers, comprising no less than 15% by weight, are combined with elastic matrix fibers and elastic yarns to form a multi-path heterogeneous yarn system. This proportion breaks through the industry's conventional low-proportion embedding mode, providing sufficient conductive cross-section for forming a low-resistance equipotential shielding network. However, when a high proportion of rigid metal fibers directly participates in high-speed knitting, their brittle nature and easy oxidation characteristics can lead to frequent fiber breakage and blackening failure. To address this, an anti-oxidation protective coating is pre-applied to the surface of the metal conductive fibers, and they are twisted together with the elastic matrix fibers to form a core-sheath composite yarn. The anti-oxidation coating chemically blocks the oxidation path of the metal layer, while the twisted strands physically encapsulate the metal fibers with elastic matrix fibers. The synergistic effect of these two processes ensures that the metal fibers are neither oxidized nor corroded nor mechanically damaged during subsequent high-speed weaving, thus guaranteeing that the high proportion of metal fibers can enter the weaving process intact.

[0021] In the process setup of multi-channel knitting equipment, pre-treated composite yarns and elastic yarns are fed in simultaneously as multiple heterogeneous yarns. Due to the significant difference in modulus between conductive metal fibers and elastic matrix fibers such as aramid, the equipment independently controls the feeding tension of each yarn, keeping the tension difference within the preset process tolerance range. This tension coordination mechanism ensures that heterogeneous yarns with different moduli can be uniformly looped in the same looping system without local breakage or coil deformation. During the looping process, conductive metal fibers are wrapped and locked inside the fabric by the coil structure of elastic matrix fibers, forming an embedded conductive network. This embedded structure is not a simple position transfer, but is deeply bound to the integrated blending process. It is precisely because of the multi-channel synchronous feeding and tension coordination control that the metal fibers can be precisely wrapped by the matrix coils at the moment of looping, thereby completely eliminating the risk of snagging, breakage, and detachment caused by the conductive fibers floating on the surface in the subsequent hook and stitch process. At the same time, it avoids the shielding blind spots caused by the needle holes of the seams, so that the fabric forms a continuous and seamless integrated structure from the fingertips to the wrist.

[0022] In the wrist area of ​​the shielding glove, the weaving equipment automatically switches the yarn ratio, increasing the feed of elastic core-spun yarn to weave a denser rib closure. This structure forms a gradient elasticity synergy system with the spandex elastic yarn in the palm and finger body area: the body area relies on spandex to allow flexible bending of the five fingers, while the wrist area relies on the high resilience of the elastic core-spun yarn to achieve a durable tight seal. Together, they prevent electric fields from intruding from the wrist gaps. At the same time, the conductive lining connecting strip sewn on the outside of the wrist area is directly connected to the integrated embedded conductive network of the glove body through built-in metal leads and crimped conductive terminals. The crimping process of the terminals ensures a low-resistance connection between the metal leads and the conductive strip of the outer shielding suit, so that the glove is no longer an isolated shielding unit, but forms a continuous equipotential body with the whole-body shielding suit system.

[0023] After weaving, the fabric undergoes a low-temperature relaxation hot air setting treatment, with the setting temperature not exceeding 80 degrees Celsius. This upper temperature limit, together with the anti-oxidation coating of the metal conductive fiber, forms a thermal protection synergy: if the anti-oxidation coating is removed, even low-temperature setting cannot completely prevent the slow oxidation of the metal layer; and if the low-temperature setting constraint is removed, the anti-oxidation coating may also fail at high temperatures. Together, they ensure that the metal conductive layer maintains chemical stability and conductive activity during the finishing process. Under this synergistic protection, the DC resistance of the fabric is stably in the range of two to four ohms, which is significantly lower than the resistance value of products with subsequent hook-and-sew processes. Moreover, after repeated bending, friction, and long-term wear, the resistance drift is minimal, achieving long-term stability of shielding performance. Attached Figure Description

[0024] Figure 1 This is a schematic flowchart of the method for preparing equipotential shielding fabric based on general conductive composite yarn in this application. Detailed Implementation

[0025] 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 a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0026] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0027] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0028] Current shielding gloves and fabrics generally employ a process where, after the base fabric is woven, conductive silver wires or fibers are attached to the fabric surface as floats via a subsequent manual hook-stitching process. While this process achieves basic conductive connectivity, the conductive wires are completely exposed on the fabric surface. Under repeated bending, friction, wearing and pulling, and in daily working environments, they are highly susceptible to snagging, breakage, and detachment, leading to localized disruptions in the conductive network. This results in a rapid decline in shielding performance over time, posing serious safety hazards. Furthermore, the subsequent hook-stitching process is a secondary, additional step, inevitably creating needle holes and localized stress concentration points on the fabric surface. This not only compromises the structural integrity of the fabric itself but also makes it difficult to ensure uniform coverage of the conductive wires across the entire stress-bearing area of ​​the palm and fingers, easily creating shielding blind spots. Although some low-voltage antistatic glove technologies attempt to embed a low proportion of flexible carbon fiber conductive filaments during the weaving process, the proportion of conductive fibers is typically only two to four percent. Furthermore, carbon fiber itself is flexible, and its material properties, conductivity mechanism, and process requirements differ fundamentally from the rigid metal conductive fibers required for high-voltage live-line work scenarios. Therefore, this type of technology does not solve the problems of filament breakage, oxidation, and tension mismatch when a high proportion of rigid metal conductive fibers directly participates in high-speed knitting, nor does it address the low-resistance, high-stability equipotential shielding requirements of shielding clothing systems. There has long been a technological bias in the existing technology, namely that conductive metal fibers such as silver, stainless steel, copper, and iron, due to their brittleness, easy oxidation and blackening, and significant modulus differences compared to aramid and elastic yarns, cannot be directly used as the main yarn in knitting at a high proportion of more than 15%. Otherwise, it would inevitably lead to frequent filament breakage, stiff fabrics, loss of elasticity, and inability to mass-produce. Therefore, the industry has consistently avoided moving the metal conductive function forward to the weaving process, relying instead on the compromise of subsequent stitching.

[0029] This application addresses the technical bias that high-proportion rigid metal conductive fibers are brittle, easily oxidized, and have a significant difference in modulus compared to elastic matrix fibers, making them difficult to directly participate in high-speed knitting. It proposes using metal conductive fibers, elastic matrix fibers, and elastic yarns as multiple heterogeneous yarns. After pretreatment with an anti-oxidation coating and twisted ply bonding, these yarns are synchronously and integrated through a multi-channel knitting machine. This allows the metal conductive fibers to be embedded within the loop structure of the elastic matrix fibers rather than floating on the surface. Simultaneously, heterogeneous tension is used to collaboratively control loop uniformity, and a low-temperature relaxation hot air setting at no more than 80 degrees Celsius is used to protect the metal conductive layer. This creates a continuous and long-lasting stable low-resistance conductive path throughout the entire fabric without seams, achieving a fusion of shielding function and the fabric's structural integrity.

[0030] This application describes an equipotential shielding fabric constructed by simultaneously weaving multiple heterogeneous yarns into a seamless, one-piece structure using a multi-channel knitting machine. Specifically, conductive metal fibers, elastic matrix fibers, and optional elastic yarns are used as multiple functional yarns, fed synchronously and at a uniform speed by a fully automated multi-channel computer-controlled circular knitting machine, forming the entire fabric in a single, one-time process from start to finish. This configuration allows each component yarn to participate in the weaving process simultaneously during loop formation, rather than weaving the base first and then adding conductive fibers later. This synergistic effect eliminates traditional seams and secondary stitching processes, resulting in a fabric with a complete structure, no electromagnetic leakage points, and continuous shielding boundaries.

[0031] In some embodiments, the weight percentage of conductive metal fibers is not less than 15%. Specifically, at least one of silver, stainless steel, copper, or iron fibers can be selected and blended with elastic matrix fibers at a weight ratio of 15% to 25%. This ratio is significantly higher than the 2% to 4% conductive fiber ratio in existing low-voltage antistatic fabrics. Combined with the skeletal support of the elastic matrix fibers, a sufficiently dense conductive cross-section is formed within the fabric, generating a low-resistance and globally continuous conductive network. This allows the fabric's DC resistance to stably reach 1Ω to 5.5Ω, meeting the stringent requirements of equipotential shielding for high-voltage live-line work.

[0032] In some implementations, the conductive metal fibers are embedded within the coil structure of the elastic matrix fibers. Specifically, the conductive metal fibers are wrapped and locked into the fabric structure by the coils of the elastic matrix fibers during the weaving stage, rather than floating on the fabric surface as loose threads. This embedded structure, in conjunction with the integrated blending process, ensures that the metal fibers are precisely wrapped by the matrix coils at the moment of loop formation. This results in the conductive fibers being protected from external mechanical snagging and friction damage, fundamentally eliminating the risk of localized shielding failure caused by the breakage and detachment of conductive fibers.

[0033] In some embodiments, the elastic matrix fiber is aramid flame-retardant and high-temperature resistant fiber. Specifically, aramid fiber accounts for 65% to 80% of the fabric substrate by weight, and is simultaneously blended with conductive metal fibers and elastic yarns. The high strength, flame retardancy, and arc resistance of aramid, combined with the conductivity of the conductive metal fibers, provide a mechanical protective carrier for the metal fibers and endow the fabric with basic flame-retardant and high-temperature resistant protective capabilities, resulting in the technical effect of no continuous combustion upon exposure to open flame, no melting and dripping, and resistance to damage over long-term wear.

[0034] In some embodiments, the multi-layer heterogeneous yarn also includes elastic yarn, which includes at least one of spandex elastic yarn and elastic core-spun elastic yarn. Specifically, spandex elastic yarn is incorporated into the palm and finger body area at approximately 5% of the yarn composition, while elastic core-spun elastic yarn is used in the wrist rib area at approximately 5% of the yarn composition. The spandex and elastic core-spun yarn work together, with the former providing elasticity and resilience to the palm and finger body area, and the latter forming a highly elastic and dense rib in the wrist area. This produces a technical effect of flexible finger movement, a tight and sealed wrist, and lasting resilience without loosening, preventing electric fields from penetrating through the wrist gaps.

[0035] In some embodiments, the surface of the metal conductive fiber is provided with an anti-oxidation protective coating. Specifically, an anti-oxidation protective layer is applied to the surface of the metal conductive fiber before it enters the weaving process. This coating works synergistically with the brittle nature of the metal fiber to chemically block the oxidation and blackening path of the metal layer under high-speed weaving friction and humid and hot environments. This results in a reduced fiber breakage rate and maintains the chemical stability of the conductive layer, ensuring that the metal fiber maintains low resistance characteristics in subsequent processes.

[0036] In some embodiments, conductive metal fibers and elastic matrix fibers are twisted together and then fed into a multi-channel knitting machine. Specifically, brittle metal filaments and aramid yarns are twisted together in multiple strands to form a composite yarn with a core-sheath structure. The twisting and twisting process works synergistically with an anti-oxidation coating. The former physically coats the metal fibers with elastic matrix fibers, while the latter chemically protects the metal surface. Together, they ensure that the metal fibers are protected from mechanical damage and oxidative corrosion during high-speed knitting, resulting in improved weaving feasibility and reduced fabric skipping and breakage.

[0037] In some implementations, the DC resistance of the fabric ranges from 1Ω to 5.5Ω. Specifically, this is achieved through a combination of factors: a high proportion of at least 15% conductive metal fibers; an embedded conductive network structure; a composite pretreatment involving an anti-oxidation coating and twisted strands; and an integrated blending process with synergistic control of heterogeneous tension. This multi-factor synergy results in a tightly bound, low-contact-resistance interface between the metal fibers and the elastic matrix fibers, producing a resistance value far below the 15Ω standard limit and approximately 40% lower than traditional post-stitching processes, while simultaneously ensuring long-term stability of the resistance value.

[0038] In some embodiments, the shielding glove includes a palm and finger body area and a wrist area, which are synchronously and integrally woven from multiple heterogeneous yarns using a multi-channel knitting machine, forming a seamless integral shape from the fingertips to the wrist. Specifically, the palm and finger body area of ​​the glove is synchronously woven from aramid, conductive metallic yarn, and spandex. The conductive metallic fibers are embedded within the glove's fabric structure and interwoven with the elastic matrix fibers to form a continuous conductive path throughout the entire area. This design ensures a continuous conductive network in the finger folding areas and between the fingers, which, combined with the seamless integral structure, produces a technical effect of no blind spots and consistent conductivity between the left and right gloves.

[0039] In some embodiments, the wrist cuff area features a densely ribbed seam, and a conductive lining connecting strip with an embedded metal lead wire is provided on the outer side of the wrist cuff area. The lead wire end is crimped with a conductive terminal. Specifically, during the weaving stage, the wrist cuff area is automatically fed with elastic core-spun yarn to create a dense ribbed seam. The outer side is smoothly sewn with the conductive lining connecting strip containing the embedded metal lead wire, and the end is crimped with a brass locking conductive terminal using a special mold. The dense ribbed seam and the conductive lining connecting strip work together; the former seals the electric field intrusion channel at the wrist level from the fabric body level, while the latter provides a reliable low-resistance connection with the conductive strip of the full-body shielding suit from the system connection level, resulting in the technical effect of the glove and shielding suit system forming a complete human body equipotential shielding system.

[0040] In some embodiments, the preparation method includes pre-treating the conductive metal fibers and elastic matrix fibers to form an anti-oxidation protective layer on the surface of the conductive metal fibers, and / or twisting the conductive metal fibers and elastic matrix fibers together. Specifically, an anti-oxidation coating is first applied to the surface of the conductive metal yarn, and then it is twisted together with the aramid matrix yarn. The anti-oxidation coating and the twisted strands work synergistically to address the risks of chemical oxidation and mechanical breakage of the metal fibers, resulting in a technical effect that enables high-proportion rigid metal fibers to be knitted at high speeds.

[0041] In some embodiments, the preparation method includes simultaneously feeding the processed multi-channel heterogeneous yarns into a multi-channel knitting device, controlling the feeding tension of each yarn to keep the tension difference between the conductive metal fibers and the elastic matrix fibers within a preset process tolerance range. Specifically, due to the significant difference in modulus between the conductive metal fibers and the aramid matrix fibers, the device implements independent tension control for each yarn, strictly limiting the tension difference within the allowable process range. This tension coordination mechanism, in conjunction with the multi-channel synchronous feeding setting, enables heterogeneous yarns with vastly different moduli to be uniformly looped in the same looping system, resulting in a smooth fabric surface, consistent loop density, and no localized breakage of the metal fibers or deformation of the loops.

[0042] In some embodiments, the preparation method includes embedding conductive metal fibers within the coil structure of elastic matrix fibers through integrated weaving, forming a continuous conductive path throughout the fabric, resulting in a seamless, one-piece molded fabric. Specifically, multiple yarns are simultaneously looped in a multi-channel knitting machine, and the conductive metal fibers are enveloped and locked by the coil structure of the elastic matrix fibers during the looping process. This setup, combined with pre-treatment and tension control, ensures that a high proportion of the conductive metal fibers are fully embedded only when the metal fibers are protected against oxidation and twisting, and the tension is properly matched. This results in a fabric with uniform conductivity throughout, no seams, and no blind spots.

[0043] In some embodiments, the preparation method includes low-temperature relaxation hot air setting of the fabric, with the setting temperature not exceeding 80°C. Specifically, hot air not exceeding 80°C is used to relax and set the woven fabric. This upper temperature limit works in conjunction with the anti-oxidation protective coating. Without the anti-oxidation coating, even low-temperature setting cannot completely prevent the slow oxidation of the metal layer; without the constraint of low-temperature setting, the anti-oxidation coating may also fail at high temperatures. Together, they ensure that the conductive metal layer maintains chemical stability and conductive activity during the finishing process, resulting in a smooth fabric pattern, elimination of internal stress, and no damage to the conductive layer.

[0044] In some implementations, when the fabric is a shielding glove, the elastic core-spun yarn is automatically fed into the wrist area during the integrated blending process to form a denser rib closure. Specifically, the multi-channel knitting equipment automatically adjusts the yarn ratio when the needles reach the wrist area, increasing the feeding amount of elastic core-spun yarn. This automatic switching setting works in conjunction with the integrated blending process to ensure seamless connection between the wrist rib and the glove body in the same weaving process, eliminating the need for secondary cutting and sewing. This results in the technical effects of durable elastic tightening at the wrist, sealing the electric field intrusion channel, and improving production efficiency.

[0045] Example 1 This embodiment uses silver conductive filaments and aramid staple fiber yarns twisted together to prepare shielding gloves. Silver conductive filaments with a linear density of 22 dtex are selected as the conductive metal fiber, aramid 1313 flame-retardant staple fiber with a density of 21 Ne is selected as the elastic matrix fiber, 20 D spandex bare yarn is selected as the elastic yarn, and 70 D elastic core-spun yarn is selected as the special yarn for the wrist cuff ribbing. By mass percentage, the silver conductive filaments account for 18%, aramid 1313 accounts for 72%, spandex bare yarn accounts for 5%, and elastic core-spun yarn accounts for 5%. In the raw material pretreatment stage, silver conductive filaments are first impregnated and coated with a layer of silicone-modified polyurethane anti-oxidation protective coating, with the coating thickness controlled between 0.8μm and 1.2μm. After drying at a low temperature of 60℃, two silver conductive filaments are twisted together with one aramid 1313 yarn, with the twist set at 380 twists / m, forming a core-sheath composite conductive yarn, in which the aramid is wrapped in the outer layer and the silver filaments are located in the core layer. A fully automatic multi-channel computerized circular knitting machine is used for integrated blending and weaving. This machine is equipped with a four-way independent yarn feeding system, feeding the composite conductive yarn, aramid base yarn, spandex bare yarn, and elastic core-spun yarn respectively. During weaving, the feeding tension of the composite conductive yarn is set to 0.22 N, the tension of the aramid base yarn is 0.28 N, and the tension of the spandex bare yarn is 0.15 N. The tension difference among the three is controlled within the process tolerance range of 0.13 N, and the machine speed is set to 280 r / min. The palm and finger area is constructed using a three-way synchronous blend of composite conductive yarn, aramid base yarn, and bare spandex yarn, forming a dense single-sided plain weft knit structure with a density of 32 stitches / inch. When the knitting needles reach the wrist area, the equipment automatically switches to a fourth yarn feed system, increasing the feeding ratio of elastic core-spun yarn to create a 2×2 dense rib finish with a rib height of 18mm. After weaving, the glove blank undergoes low-temperature relaxation hot air setting in a 75℃ hot air setting machine for 12 minutes. The finished product was tested, and the DC resistance was 2.6Ω, far below the standard limit of 15Ω. Flame retardant performance testing showed a 0-second afterflame time, a 0.5-second smoldering time, and no melting drips. The tear strength was 85 N in the warp and 78 N in the weft. After 5000 cycles of friction at 9 kPa on a Martindale abrasion tester, the DC resistance increased to 3.1Ω, an increase of only 19%, indicating a stable conductive network structure.

[0046] Example 2 This embodiment uses stainless steel fibers to prepare the shielding fabric. Stainless steel filament bundles with a diameter of 8 μm and a linear density of 55 dtex are selected as the conductive metal fibers. 20 Ne aramid 1313 yarn is selected as the elastic matrix fiber, and 20 D spandex bare yarn and 70 D elastic core-spun yarn are selected as the elastic components. By mass percentage, stainless steel fiber accounts for 20%, aramid 1313 for 70%, spandex bare yarn for 5%, and elastic core-spun yarn for 5%. Since the rigidity of stainless steel fibers is significantly higher than that of silver fibers, a double-layer anti-oxidation coating process is used in the pretreatment stage. First, a layer of nano-silica sol is coated on the surface of the stainless steel filament bundle, followed by a layer of silicone-modified acrylate topcoat, with the total coating thickness controlled at 1.5 μm. Subsequently, three stainless steel filament bundles are twisted together with two aramid 1313 yarns at a twist of 420 twists / m to form a highly cohesive composite conductive yarn. The weaving equipment used was a multi-channel computerized circular knitting machine. The feed tension of the composite conductive yarn was 0.25 N, the aramid base yarn tension was 0.30 N, and the spandex tension was 0.16 N, with the tension difference controlled within 0.11 N. The rotation speed was reduced to 260 r / min to minimize the risk of yarn breakage. The fabric structure was a high-density single-sided plain knit with a density of 30 stitches / inch. Finishing involved 78℃ low-temperature relaxation hot air setting for 15 minutes. The finished fabric had a DC resistance of 3.2Ω. Flame retardancy tests showed a 0 s afterflame time and a 0.8 s smoldering time. After 5000 cycles of Martindale abrasion resistance testing, the resistance was 3.8Ω, an increase of 18.8%. When this fabric was made into shielding gloves, elastic core-spun yarn was automatically woven into the wrist area to form a dense rib. A conductive lining with an internal copper metal lead was sewn onto the outside, with brass terminals crimped to the ends of the leads. The conductivity between the terminals and the glove body was 0.3Ω.

[0047] Example 3 The third embodiment uses copper fiber to prepare shielding gloves. Copper fiber filaments with a linear density of 68 dtex are selected as the conductive metal fiber, 21 Ne aramid 1313 yarn is selected as the elastic matrix fiber, and 20 D spandex bare yarn and 70 D elastic core-spun yarn are selected. By mass percentage, copper fiber accounts for 15%, aramid 1313 accounts for 77%, spandex bare yarn accounts for 4%, and elastic core-spun yarn accounts for 4%. Copper fiber surfaces are prone to oxidation and blackening; therefore, acid washing and activation are performed to remove the surface oxide film during pretreatment, followed by coating with a benzotriazole corrosion inhibitor and an organosilicon composite anti-oxidation coating, with a coating thickness of approximately 1.0 μm. Two copper fiber filaments are twisted together with one aramid yarn at a twist of 350 twists / m. During weaving on a multi-channel circular knitting machine, the tension of the composite conductive yarn is 0.24 N, the tension of the aramid base yarn is 0.29 N, and the tension of the spandex yarn is 0.15 N, with the tension difference controlled within 0.14 N, and the rotation speed is 290 r / min. The fabric density is 31 stitches / inch. Finishing involves 72°C low-temperature relaxation hot air setting for 10 minutes. The finished product's DC resistance is 3.8 Ω. Flame retardancy testing showed a 0-second afterflame time and a 0.6-second smoldering time. Tear strength was 82 N in the warp and 75 N in the weft. After repeated bending tests at a frequency of 1 bend / s for 1000 times, the resistance was 4.1 Ω, an increase of 7.9%, significantly lower than the resistance drift rate after bending in products using traditional post-stitching processes.

[0048] Example 4 This embodiment uses silver conductive filaments and aramid staple fiber yarns twisted together to prepare shielding socks. Silver conductive filaments with a linear density of 22 dtex are selected as the conductive metal fiber, aramid 1313 flame-retardant staple fiber with a density of 21 Ne is selected as the elastic matrix fiber, 20 D spandex bare yarn is selected as the elastic yarn, and 70 D elastic core-spun yarn is selected as the yarn specifically for the sock cuff ribbing. By mass percentage, the silver conductive filament accounts for 12%, aramid 1313 accounts for 78%, spandex bare yarn accounts for 5%, and elastic core-spun yarn accounts for 5%. This proportion of conductive filament is lower than the 18% in the aforementioned glove embodiment, due to cost control considerations, and aims to verify the process feasibility and resistance performance boundaries under a lower proportion of metal fibers.

[0049] In the raw material pretreatment stage, silver conductive filaments are first impregnated and coated with a layer of silicone-modified polyurethane anti-oxidation protective coating, with the coating thickness controlled between 0.8 μm and 1.2 μm. After drying at a low temperature of 60 ℃, two silver conductive filaments are twisted together with one aramid 1313 yarn, with the twist set at 380 twists / m, forming a core-sheath composite conductive yarn. A fully automatic multi-channel computerized circular knitting machine is used for integrated blending and weaving, equipped with a four-way independent yarn feeding system. During weaving, the feed tension of the composite conductive yarn is set to 0.22 N, the tension of the aramid base yarn is 0.28 N, and the tension of the spandex bare yarn is 0.15 N. The tension difference among the three is controlled within the process tolerance range of 0.13 N, and the machine speed is set to 280 r / min. The main body area of ​​the sock is formed by the simultaneous blending of the composite conductive yarn, aramid base yarn, and spandex bare yarn, creating a dense single-sided plain knit structure with a density of 32 stitches / inch. When the knitting needles reach the sock cuff area, the equipment automatically switches to the fourth yarn feeding system, increasing the feeding ratio of elastic core-spun yarn to knit a 2×2 dense rib cuff with a rib height of 22 mm. After knitting, the sock blank undergoes low-temperature relaxation hot air setting in a 75 ℃ hot air setting machine for 12 minutes.

[0050] The finished product was tested by Guangzhou Hengli Testing Co., Ltd., report number 01-2026070801, sample receipt date 2026-07-08, test date 2026-07-08, and the test was conducted according to the Preventive Testing Procedure for Live Working Tools, Devices and Equipment DL / T 976-2017. The DC resistance test value of sample number 012626800214 was 4.7 Ω, and the DC resistance test value of sample number 012626800215 was 5.1 Ω. The standard resistance value for both samples is ≤15 Ω, and both test results meet the requirements, therefore the test conclusion is qualified. The ambient temperature was 23 ℃, and the ambient humidity was 49%. This resistance value is higher than the 2.6 Ω and 3.3 Ω of the glove product in the first embodiment, directly attributed to the reduction in the proportion of silver conductive filaments from 18% to 12%, resulting in a corresponding decrease in conductive cross-sectional density and thus an increase in resistance. However, even at this lower ratio, the resistance value of the shielding socks is still far below the standard limit of 15 Ω, verifying the adaptability and reliability of the integrated blending process of this application under different metal fiber ratios.

[0051] If the proportion of conductive wire is increased to 15% or more, referring to the ratio range of the first to third embodiments, a more excellent resistance value can be achieved. For example, with the 18% ratio set in the first embodiment, the DC resistance of the shielding sock is expected to reach the range of 3Ω to 4Ω; if it is further increased to 20%, referring to the stainless steel fiber scheme of the second embodiment, the resistance is expected to drop to about 3.2Ω. This shows that the integrated blending process of this application has wide ratio adaptability. Users can flexibly adjust the proportion of metal conductive fiber within the range of 12% to 25% according to the balance between cost constraints and performance requirements, and the product can be guaranteed to meet the basic resistance requirements of equipotential shielding for live-line work. When the application scenario has more stringent requirements for resistance performance, only the proportion of metal fiber needs to be increased to achieve lower resistance without changing the core process route, which reflects the versatility and scalability of the technical solution of this application.

[0052] Comparative Example 1 This comparative example uses a traditional manual crochet process to prepare shielding gloves. The same raw material specifications and weight ratios as Example 1 were used: 18% silver conductive filaments, 72% aramid 1313, 5% spandex, and 5% elastic core-spun yarn. However, the manufacturing process was different: first, the glove base was woven using aramid, spandex, and elastic core-spun yarn; then, the silver conductive filaments were manually crocheted to the surface of the fabric in the palm and finger areas using a crochet hook, with the conductive filaments distributed intermittently along the longitudinal direction of the fingers. The initial DC resistance of this comparative example glove was 4.6 Ω. After 5000 cycles of Martindale abrasion resistance testing, multiple breaks and detachments of the surface conductive filaments occurred, and the resistance rose to 18.5 Ω, exceeding the standard limit of 15 Ω, thus being deemed unqualified. After 1000 repeated bending cycles, the resistance rose to 22 Ω, and three obvious filament breaks and one detached conductive filament appeared in the palm and finger areas. Although the flame retardant performance is comparable to that of the example, the shielding performance decays rapidly with use and cannot meet the long-term stability requirements of equipotential shielding for live-line work.

[0053] The above description is merely an exemplary embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the technical concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. An equipotential shielding fabric based on universal conductive composite yarn, characterized in that, The fabric is constructed by simultaneously and integrally weaving multiple heterogeneous yarns into a seamless, one-piece structure using a multi-channel knitting machine. The multiple heterogeneous yarns include conductive metal fibers and elastic matrix fibers. The conductive metal fibers account for no less than 15% of the weight of the conductive metal fibers, and the conductive metal fibers are embedded within the coil structure of the elastic matrix fibers, forming a continuous conductive path throughout the fabric.

2. The equipotential shielding fabric based on universal conductive composite yarn according to claim 1, characterized in that, The conductive metal fiber includes at least one of silver metal fiber, stainless steel fiber, copper fiber, and iron fiber; and / or, the elastic matrix fiber is aramid flame-retardant and high-temperature resistant fiber.

3. The equipotential shielding fabric based on universal conductive composite yarn according to claim 1, characterized in that, The multi-path heterogeneous yarn also includes elastic yarn, which includes at least one of spandex elastic yarn and elastic core-spun elastic yarn; By weight percentage, the conductive metal fiber accounts for 15% to 25%, the elastic matrix fiber accounts for 65% to 80%, and the elastic yarn accounts for 3% to 10%.

4. The equipotential shielding fabric based on universal conductive composite yarn according to claim 1, characterized in that, The surface of the metal conductive fiber is provided with an anti-oxidation protective coating; And / or, the conductive metal fiber and the elastic matrix fiber are twisted together and then fed into the multi-channel knitting equipment.

5. The equipotential shielding fabric based on universal conductive composite yarn according to claim 1, characterized in that, When the fabric has a cuff area, the cuff area of ​​the fabric is woven with high-elasticity yarn by automatically switching the yarn ratio to form a dense rib closure. And / or, the metal conductive fiber is embedded within the coil structure of the elastic matrix fiber during the weaving stage.

6. The equipotential shielding fabric based on universal conductive composite yarn according to any one of claims 1 to 5, characterized in that, The DC resistance is 1Ω~5.5Ω.

7. A shielding glove composed of the equipotential shielding fabric described in any one of claims 1-6, comprising a palm and finger body area and a wrist area, characterized in that, The glove is formed by synchronously and integrally blending multiple heterogeneous yarns through a multi-channel knitting device. The multiple heterogeneous yarns include conductive metal fibers and elastic matrix fibers. The conductive metal fibers account for no less than 15% of the weight of the conductive metal fibers. The conductive metal fibers are embedded in the glove fabric structure and interwoven with the elastic matrix fibers to form a continuous conductive path throughout the entire area. The glove is integrally formed without splicing from the fingertips to the wrist.

8. The shielding glove according to claim 7, characterized in that, The wrist opening area has a dense ribbed closure; a conductive lining connecting strip is provided on the outer side of the wrist opening area, the conductive lining connecting strip has a built-in metal lead wire, and the end of the metal lead wire is crimped with a conductive terminal.

9. A method for preparing an equipotential shielding fabric based on a universal conductive composite yarn as described in any one of claims 1-6, characterized in that, Includes the following steps: Step 1: Perform a pre-composite treatment on the metal conductive fiber and the elastic matrix fiber to form an anti-oxidation protective layer on the surface of the metal conductive fiber, and / or, twist the metal conductive fiber and the elastic matrix fiber together. Step 2: The processed metal conductive fibers, elastic matrix fibers, and elastic yarns are fed into a multi-channel knitting equipment as multiple heterogeneous yarns. The feeding tension of each yarn is controlled so that the tension difference between the metal conductive fibers and the elastic matrix fibers is kept within the preset process tolerance range. Step 3: By integrating the metal conductive fibers into the coil structure of the elastic matrix fibers through integrated weaving, a continuous conductive path is formed throughout the entire area, resulting in a seamless integral fabric. Step 4: Perform low-temperature relaxation hot air setting on the fabric, with the setting temperature not exceeding 80℃.

10. The preparation method according to claim 5, characterized in that, In step 3, when the fabric has an armhole area, the elastic core-spun yarn is automatically fed into the armhole area to form a dense rib closure.

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