High-frequency wire and preparation method thereof

Abstract

The invention relates to a high-frequency wire and a preparation method thereof, in particular to a wire coping with a skin effect and suitable for high-frequency alternating current and a preparation method thereof, which can reduce the use amount of a metal power transmission material and enable the wire to be light and flexible. The high-frequency wire is of a multi-layer structure, and a core layer of the high-frequency wire is made of chemical fibers, drafted to be close to the ultimate stretch rate and shaped; a copper and / or carbonaceous and / or silver and / or gold conductive layer is plated on the surface outside the core layer; the thickness of the conductive layer is equivalent to the skin depth of a corresponding material under the application frequency; the preparation method comprises the steps of core making, surface treatment, primary plating, conductive layer plating and post-treatment, and the conductive layer is fixed outside the non-conductive core layer to form a hollow wire with electrical characteristics.

Description

TECHNICAL FIELD

[0001] The present application relates to a high-frequency wire and a preparation method thereof, and more particularly to a wire and a preparation method thereof for coping with skin effect and suitable for high-frequency alternating current, which can reduce the amount of metal power transmission material and make the wire lightweight and flexible. BACKGROUND

[0002] Generally, electric machines (including motors, generators and transformers) and power inductors are both composed of copper and iron, i.e., both include a magnetic core (iron) and a winding (copper), and work in an electric-magnetic interactive environment to realize the conversion between electricity and magnetism.

[0003] With the development of power electronics technology, electric machines and power inductors have entered a high-frequency working environment from a traditional power frequency working environment. In the high-power and high-voltage application scenarios, the working frequency is increased from the traditional power frequency (50 / 60 Hz) to 20 KHz level based on the basic requirement of avoiding audible noise under the primary technology level of switching power supply. In the small-power switching power supply application scenarios, the primary level is 40 / 50 Hz. In recent years, with the breakthrough in the performance of power components and the rapid development of control circuit technology, the working frequency in the high-power and high-voltage application scenarios has been increased to more than 40 KHz, and the working frequency in the small-power switching power supply application scenarios has broken through the MHz level. The beneficial effects are that the electric machines and power inductors are greatly reduced in size and weight, and the cost and efficiency are greatly reduced.

[0004] As is known to all, alternating current has skin effect in a wire, and the higher the frequency, the more obvious the skin effect, and the lower the resistivity of the wire, the more obvious the skin effect. That is, when the alternating current flows through the wire, the current density of the outer layer of the wire is greater than that of the inner layer (the current is concentrated in the outer layer of the wire and flows), and the higher the frequency, the higher the concentration. Taking a copper wire as an example, at 20 KHz, the skin depth is 467 um (the current is basically concentrated in the outer layer of the wire within 467 um, and the current density is very low within a radius of 467 um), and the skin depth at 100 KHz is only 209 um.

[0005] As mentioned above, because of the conductor carrying alternating current, its inner layer is "useless", therefore, in the traditional technology, in order to reduce the cost or reduce the weight, the conductor is designed as a hollow structure, or a copper-clad aluminum structure, or a flat structure. However, ① because the conductor needs to be wound on the magnetic core in a winding manner in the application of motor and power inductor and other products, the cavity of the hollow conductor will inevitably be irreversibly squeezed during the winding process, making the hollow conductor become a nearly solid structure, the original design intention is lost, or the winding process is greatly difficult, the cost rises, or the practicability is poor; ② although the copper-clad aluminum has a lower material cost than the full copper, the manufacturing process is more complex, and because the ductility of aluminum is much lower than that of copper, there is a big difference in parameters such as expansion coefficient, although the copper-clad aluminum conductor has been widely used in KW level and above power motor and power inductor and other products, its contribution to weight reduction is not great, and in small power applications, due to the difficulty of manufacturing process of small diameter copper-clad aluminum conductor, the yield is reduced due to factors such as ductility, so there is little progress; ③ the flexibility of the flat structure conductor is greatly reduced, the winding difficulty is greatly increased, and special equipment is needed to cooperate according to different process requirements, therefore, the flat structure conductor is currently only used in medium and high power applications, and the cost is high in the case of insufficient batch.

[0006] The conductive fiber technology has appeared in the textile industry many years ago, which is to plate a conductive layer such as copper or silver on the surface of an insulating chemical fiber to make the fiber have conductive performance. In principle, the structure of the conductive fiber is exactly matched with the application needs of high-frequency current, and can be suitable for the conductive demand under the skin effect. However, due to the limitations of manufacturing method and cost, etc., when the existing conductive fiber is subjected to external force operations such as bending, impact, extrusion and friction, the conductive layer on the surface will be broken due to the difference in ductility between the fiber core and the surface plating layer, making the conductive layer of the conductive fiber become conductive segments or conductive particles, which destroys the performance of a single conductive fiber. Therefore, the conductive fiber in the existing technology can only be used in the form of conductive segments or conductive particles to form a network structure after being woven into a conductive cloth, which is used for electromagnetic shielding and radiation protection in special environments, or is applied to antibiosis by using the heavy metal characteristics of the surface conductive layer. In short, the application range of the conductive fiber product in the existing technology is extremely narrow.

[0007] In the existing technology, the plating process of the conductive fiber adopts the weaving immersion plating method, that is, the fiber to be plated is woven into a sock or cloth, immersed in the plating solution for a period of time, then taken out, and then unwound into a fiber roll for use. The reason for adopting this process is that the plating process is slow, which takes dozens of minutes or even hours, and if the fiber is plated in a fiber state, a large-sized plating tank is needed, which not only needs to occupy a large space, but also needs a large amount of plating solution to fill the plating tank. Under the current condition of small batch, no manufacturer can make such investment, and the idle rate is too high after investment, and the input-output is too low.

[0008] Because the existing plating technology is woven immersion plating, the plating process is static immersion plating, and the plating layer is like a dust layer deposited on the surface of the object in a closed environment, the adhesion and the strength of the plating layer itself are weak, which leads to the plating layer being easily broken. Moreover, due to the use of woven immersion plating, there are a large number of intersection points between the fibers, the gap at each intersection point is small, and the contact space with the plating solution is much smaller than other positions, so the plating layer thickness at each intersection point is different from other positions, resulting in uneven plating layer, affecting the overall conductivity and overall strength of the plating layer. If the plating time is lengthened to compensate, although the plating thickness can be increased, the uneven plating problem cannot be solved, and if the plating time continues to be lengthened, the plating layer at the intersection point may be adhered, and the plating layer at the intersection point may be torn when the fibers are disassembled after the plating is completed, affecting the overall conductivity and overall strength of the plating layer, and the plating thickness is also limited.

[0009] Therefore, in the prior art, the weight ratio of the plating layer of the conductive fiber is less than 20%, and the thickness upper limit is only about 0.3um. Obviously, the plating layer with such thickness cannot bear the task of transmitting current even if the plating layer does not break, and does not have the conditions to replace the existing enameled wire in the motor and power inductor.

[0010] In summary, the conductive fiber of the prior art meets the transmission requirements of high-frequency current in structure, but its process and product performance are far from replacing the enameled wire in the prior art. Therefore, the key to solving the above problems is to implement low-cost, lightweight, high-strength and high-flexibility of the inner layer of the wire, and the conductivity of the inner layer of the wire does not need to be concerned. Due to the large-scale popularization of high-frequency applications, it is determined that the market demand is great, the application range is wide, and the market needs a lighter, more suitable for winding application, and more wire diameter specifications of the wire to replace the traditional enameled wire. SUMMARY

[0011] The present application provides a temperature characteristic detection device and method to solve the problems of the prior art.

[0012] According to the actual needs, one or more embodiments of the present application provide a temperature characteristic detection device and method to solve the limitations and defects of the current technology listed in the background art, and provide a practical solution. The technical scheme of the present application is as follows: The application provides a high-frequency wire and a preparation method thereof. The high-frequency wire is a multi-layer structure. A core layer is made of chemical fiber, which is stretched to a limit elongation and is shaped. A conductive layer made of copper and / or carbon and / or silver and / or gold is plated on the surface of the core layer. The thickness of the conductive layer is equal to the skin depth of the corresponding material at the application frequency. The preparation method comprises the following steps. Core preparation: high polymer chemical materials are selected, and fibers are prepared by using a spinning process. The fibers are stretched to a limit elongation by using a drawing process and are shaped to prepare drawn yarns. Surface treatment: the drawn yarns pass through a cleaning solution to remove oil stains and impurities on the surface of the drawn yarns, and then are wound on a water-resistant and corrosion-resistant inner cylinder to form a plating cylinder. Primary plating: a primary plating solution is placed in a sealed container, and the plating cylinder is placed in the primary plating solution for more than 20 minutes. During the process, the sealed container is subjected to changing pressure to change the internal pressure of the primary plating solution, so that the primary plating solution fully contacts and flows with the surface of the drawn yarns on the plating cylinder and exchanges, and a complete and easy-to-plate film is formed on the surface of the drawn yarns. Conductive layer plating: the conductive plating solution is placed in a plating tank, and the drawn yarns on the plating cylinder pass through multiple guide rollers in the plating tank in a multiple-turn manner. The speed of the drawn yarns is controlled so that each point of the drawn yarns stays in the conductive plating solution for not less than the time required for the plating thickness, and the drawn yarns are aged and compensated in the conductive layer plating to form plated yarns. Post-processing: the plated yarns passing out of the plating tank pass through a cleaning solution and a drying area, and then are wound on a receiving cylinder to prepare a bare high-frequency wire.

[0013] In the scheme, 1) The description of “copper and / or carbon and / or silver and / or gold” refers to one of copper, carbon, silver and gold, or an alloy of any multiple materials.

[0014] 2) The chemical fiber is used as the core layer of the wire. The density of the chemical fiber is about 1-2 g / cm 3 , and the densities of copper, silver and gold are 8.96 g / cm 3 , 10.49 g / cm 3 and 19.32 g / cm 3, the density of copper, silver, gold is 5 times more than chemical fiber. Therefore, ① using chemical fiber as the core layer of the wire, can greatly reduce the weight of the wire without affecting the high-frequency conductivity, the higher the frequency of the current carried, the more significant the effect; ② compared with the aluminum core of the copper-clad aluminum wire in the prior art, the chemical fiber inner core in the present scheme has better flexibility, which can improve the flexibility of the final product (high-frequency wire) of the present scheme; ③ the solid core layer made of chemical fiber is not easy to deform compared with hollow wire during winding and bending (the deformation of hollow wire means that non-uniform extension occurs at the deformation site, that is, the cross-sectional area of the wire changes suddenly at the deformation site, which affects the consistency of impedance and also causes radiation and other hazards at the site under high-frequency current), and has a certain tensile strength, which is better than hollow wire.

[0015] 3) The chemical fiber used as the core layer is stretched close to the limit of the elongation rate and is shaped before plating the conductive layer, so that the axial ductility of the chemical fiber is close to the ductility of the plating material, which can greatly reduce the probability of plating layer fracture and peeling when the wire is subjected to external forces such as bending, impact and extrusion, and ensure the overall conductivity of the entire wire; 4) The thickness of the plating layer is comparable to the skin depth of the corresponding material at the application frequency, so that the plating layer is fully utilized. Since the cost of plating the conductive layer is positively related to the thickness of the plating layer, the thickness of the plating layer is comparable to the skin depth of the corresponding material at the application frequency, which is the most economical choice under the premise of optimal conductivity; 5) In the initial plating process, the entire bobbin is immersed in the plating solution, which can greatly improve the process execution speed, reduce the volume of the initial plating container, and reduce the initial plating cost. The key is that by applying pressure to the sealed container, the initial plating solution can flow between the fiber gaps in the bobbin and expel the air bubbles there, so that the initial plating solution is in close contact with all the fiber surfaces and flows, achieving the effect of forming a complete, uniform and easy-to-plating film on the fiber surface, which is conducive to improving the process execution effect of the subsequent plating of the conductive layer; 6) The conductive layer plating process adopts the method of multiple turns and control of wire speed, and the drawn yarn to be plated is immersed in the conductive plating solution, so that each point of the drawn yarn stays in the conductive plating solution for a sufficient time (i.e. each point of the whole drawn yarn stays in the conductive plating solution for a sufficient time), so that the conductive particles form a conductive layer on the surface of the drawn yarn to be plated. This scheme supports the use of small-size plating tank to realize uniform plating of long filaments in a disassembled plating (different from the existing technology of making socks or cloth) manner. The advantages of this scheme are: ①Supporting small-size plating tank, saving process space and cost; ②Using multiple flow turning and folding, folding and continuing to plating, so that the plating layer is subjected to multiple bending (the plating layer has stretching and extrusion) and then plating compensation, which can greatly strengthen the plating layer strength and ensure that the final product maintains the integrity of the plating layer and excellent conductive performance in the subsequent application of the winding process; ③In the disassembled plating manner, the drawn yarn to be plated does not contact and overlap, which can ensure uniform plating of the whole drawn yarn and make the plating layer thickness not limited by the intersection point in the existing weaving and plating technology, providing space conditions for thickening the plating layer; ④By adjusting the wire speed, the residence time of the drawn yarn in the plating tank can be adjusted, so as to control the plating tank thickness to adapt to the needs of different frequencies at the optimal cost.

[0016] In summary, the present scheme creatively proposes a solution to the existing technical problems listed in the background art, making it possible to apply conductive fibers (high-frequency wires) with chemical fibers as the core layer to high-frequency current transmission.

[0017] As a further technical scheme, the chemical fiber is made of polyester or polyimide. Among them, polyester is the most widely used fiber material in the textile industry, which has low cost and sufficient strength to reduce the cost of high-frequency wires with the technology of the present scheme; polyimide provides better welding resistance and moisture resistance performance with higher melting point and lower moisture return rate.

[0018] As a further technical scheme, the conductive layer is coated with an insulating paint layer; Correspondingly, the preparation method further comprises: Painting: passing the bare high-frequency wire through the painting device to coat the paint layer on the surface of the bare high-frequency wire; Curing: passing the bare high-frequency wire coated with the paint layer through the baking area or UV radiation area to cure the paint layer, and then passing through the cooling area to cool and set, forming a high-frequency wire with an insulating layer; Winding: winding the high-frequency wire with an insulating layer on the bobbin.

[0019] The present scheme provides a high-frequency wire with a paint outer layer, which directly targets the existing technology of enameled wire to make the finished product lightweight and high-softness, making the high-frequency wire more replaceable.

[0020] As a further technical solution, the conductive layer is further surrounded by an insulating yarn; Correspondingly, the preparation method further comprises: Wrapping: using a wrapping yarn process to wrap the insulating yarn on the outer layer of the bare high-frequency conductor; Winding: winding the high-frequency conductor with an insulating layer onto a bobbin.

[0021] The present solution provides a high-frequency conductor with a yarn-quality outer layer, making the finished product directly comparable to the yarn-covered wire of the prior art, lightweight and highly flexible, making the high-frequency conductor more replaceable.

[0022] As a further technical solution, the conductive layer is further plated with a non-conductive layer and / or non-conductive particles and / or non-conductive rings; Correspondingly, the preparation method further comprises: Secondary pre-plating: referring to the initial plating process, a layer of easy-to-plate layer (including glue for bonding the conductive layer) is plated on the surface of the bare high-frequency conductor; Plating an insulating layer: plating a polyester material insulating layer on the easy-to-plate layer on the surface of the bare high-frequency conductor in a whole layer or segmented or particle form.

[0023] The present solution provides a high-frequency conductor with a whole layer or segmented or particle insulating outer layer, i.e., the high-frequency conductor has a whole layer of insulating layer, or local insulation (part of the conductive layer is exposed), when the local insulation area is greater than the local exposure area, in the subsequent winding process, even if the winding is tightly wound, the local exposed parts of adjacent conductors will not come into contact. That is, the present solution uses less insulating layer to achieve insulation between conductors, which can achieve lighter weight and lower cost.

[0024] As a further technical solution, the plurality of yarn guides guide the yarn in multiple directions, causing the drawn yarn to bend in multiple directions, so that the entire drawn yarn continues to be plated with a conductive layer after bending in multiple directions during plating, i.e., bending during plating, and continuing to plate after bending, which can continuously compensate and repair the effects of bending on the plated layer, thereby strengthening the plated layer.

[0025] The present solution uses multiple yarn guides to guide the drawn yarn to bend in multiple directions continuously during plating, and each bending will cause the plated layer of the drawn yarn to stretch and compress continuously, and the entire plated layer will be subjected to aging exercise on both sides in the bending direction. The drawn yarn after bending continues to move in the conductive plating solution, which can compensate and repair the damage caused by aging exercise, so that the plated layer after compensation and repair has significantly improved strength compared to the plated layer of the prior art. The more the bending directions, the more complete the plating layer aging, compensation and repair, and the stronger the entire plated layer of the finished high-frequency conductor, which is more suitable for current transmission applications.

[0026] As a further technical solution, the guide wire device is a multi-guide wire port structure, supporting multiple drawn wires to be plated with a conductive layer at the same time, and the multiple drawn wires do not contact each other.

[0027] In the present solution, each guide wire device is provided with multiple guide wire ports, and each guide wire port can hang a drawn wire to be plated. Through different guide wire ports of the same guide wire device, different drawn wires to be plated are spatially separated to avoid contact and intersection of the drawn wires to be plated in the plating tank. The internal space of the plating tank can be fully utilized, supporting multiple drawn wires to be plated with a conductive layer at the same time, greatly improving the utilization rate of the plating tank and the process efficiency, and reducing the process cost.

[0028] As a further technical solution, the plating tank is provided with a fluid propulsion mechanism, which operates at low speed or intermittently to push the plating solution in the plating tank to flow slowly or intermittently, thereby improving the growth speed and uniformity of the plating layer.

[0029] The present solution provides a flow function for the conductive plating solution in the plating tank. If the relative speed between the drawn wire to be plated and the conductive plating solution is too large, it will affect the plating layer effect and the growth speed of the plating layer. In addition, in order to ensure the thickness of the plating layer, it is necessary to ensure the residence time of the drawn wire to be plated in the plating tank. Therefore, the wire speed of the drawn wire in the plating tank cannot be too fast, and the plating solution is relatively stable and has poor flowability. The adverse effect of the stable plating solution is that after the metal particles in the local plating solution adhere to the drawn wire to be plated, the concentration of the metal particles in the plating solution becomes smaller, the concentration of the entire plating solution is not uniform, and the subsequent growth speed and uniformity of the plating layer are directly affected. Based on this, the present solution provides a flow function for the conductive plating solution in the plating tank, which can make the plating solution flow slowly or intermittently to uniformize the concentration of the plating solution in the plating tank and improve the process speed and execution effect.

[0030] As a further technical solution, the core layer has a circular square or long circular square cross-sectional shape, which can increase the wire surface area of the high-frequency wire under a given winding space, that is, when the wire is wound on a skeleton to form a winding in subsequent applications, the winding space can be fully utilized to improve the current density and power density. Correspondingly, the spinning hole of the spinning plate is made into a circular square or long circular square shape in the spinning process.

[0031] When the wire is wound into a winding, if the cross section of the wire is circular, one point on the outer circumference of the wire contacts the adjacent wire, and a large amount of idle area is left between the adjacent wires. In the demand for high current density and high power density, the circular cross-section wire obviously wastes a lot of space, thereby limiting the further improvement of the current density and power density. In the present solution, the core layer adopts a circular square or long circular square cross-sectional structure. Compared with the circular cross-section wire, the circular square or long circular square cross-section wire has a larger surface area under the condition that the side length and the diameter are consistent (the occupied space is consistent), and after being plated with a conductive layer, the rated current-carrying capacity is larger, which can effectively improve the current density in the same space.

[0032] The reason for using the round square or long round square cross section instead of the square or rectangular cross section is that it is difficult to realize the true square or rectangular shape in actual manufacturing, and the existence of the round chamfer is more conducive to the transition of the plating layer and the strength of the entire plating layer.

[0033] As a further technical solution, the drawn yarn made by the core-making process has a cross section including a core layer, an intermediate layer and a shell layer, all of which are spinnable chemical materials, wherein: the core layer and the shell layer are connected by at least one connecting rib, most of the intermediate layer is embedded between the core layer and the shell layer, and the intermediate layer wraps the other part of the core layer except the connecting rib, and on the shell layer, a protruding window of the intermediate layer is provided; The intermediate layer is soluble in a liquid solvent; The core layer can be plated with a conductive layer, but is not soluble in a liquid solvent that can dissolve the intermediate layer; The shell layer cannot be plated with a conductive layer and is not soluble in a liquid solvent that can dissolve the intermediate layer; Correspondingly, the preparation method further comprises: In the core-making process, the spinning process is a composite spinning process, which forms the same fiber by once forming the molten core layer, intermediate layer and shell layer material through the same spinning hole; Dissolution: placing the drawn yarn made by the core-making process in a solvent that can dissolve the intermediate layer, so that the intermediate layer in the drawn yarn is dissolved in the solvent, and this process is performed between the core-making process and the surface treatment process.

[0034] This scheme adopts a one-time forming mode to integrally combine the outer insulating material of the high-frequency wire with the core layer, and the intermediate layer "supports out" (reserves) a space between the core layer and the shell layer; in the dissolution process, water or other solvents start from the protruding window of the intermediate layer to dissolve the intermediate layer, and the entire intermediate layer is removed; then, through the conductive layer plating process, the conductive plating solution enters the space reserved by the intermediate layer from the protruding window of the intermediate layer (the gap of the shell layer), and a conductive layer is plated on the surface of the core layer. The high-frequency wire made in this way has a conductive layer on the surface of the core layer inside the shell layer, which is equivalent to wrapping an insulating layer on the outer layer of the bare high-frequency wire.

[0035] Obviously, this scheme uses a one-time forming mode to make the skeleton of the high-frequency wire, which is simpler and lower in cost than painting and coating insulating yarn on the outer layer of the bare high-frequency wire.

[0036] Secondly, in the process of painting and coating insulating yarn on the outer layer of the bare high-frequency wire, there may be operations such as dismounting and rewinding the bobbin (the bobbin on which the high-frequency wire is wound), extrusion and bending, which will inevitably affect the plating layer. This scheme avoids the above operations and can effectively protect the plating layer.

[0037] As a further technical solution, the drawing yarn made by the core-making process has a multi-strand connected cross-section, that is, the multi-strands are connected by a connecting rib to form a whole, and / or the axial surface of the drawing yarn is provided with a groove to increase the surface area, thereby increasing the cross-sectional area of the plating layer and the current carrying capacity.

[0038] The axial surface area of the drawing yarn determines the surface area of the plating layer and also determines the current carrying capacity of the plating layer. In this scheme, the connecting rib is formed by the multi-strand connection of the core layer, which not only increases the cross-sectional area of the core layer, but also makes the high-frequency wire flat and increases the strength of the whole high-frequency wire. In the process of winding the winding, the surface of the traditional regular wire is easily rubbed and damaged. The structure of this scheme can protect the surface on the inside. Compared with the traditional regular wire, the surface of the high-frequency wire of this scheme is less likely to be damaged, and the current carrying capacity can be better guaranteed. BRIEF DESCRIPTION OF DRAWINGS

[0039] The application will be further described below with reference to the drawings and examples. In the drawings: Figure 1 A structure diagram of the drawing yarn passing through a multi-directional folding structure in the process of plating the conductive layer; Figure 2 A cross-sectional view of the guide wire when the multi-guide wire port is used; Figure 3 A structure diagram of a high-frequency wire with a single circular square cross-section; Figure 4 A structure diagram of a high-frequency wire with a double circular square cross-section (integrated strand type); Figure 5 A cross-sectional view of a high-frequency wire with an integrated insulation layer before dissolution; Figure 6 A cross-sectional view of a high-frequency wire with an integrated insulation layer after dissolution (skeleton). DETAILED DESCRIPTION

[0040] Example 1 - Basic preparation method of high-frequency wire Based on the demand for transporting high-frequency current, due to the skin effect in alternating current wires, the current is concentrated in the surface layer of the wire, and the core has a low current carrying ratio. Therefore, the hollow conductor scheme is considered, and the core manufacturing process includes: Core-making: selecting high molecular chemical materials, using spinning process to make fibers, and using drawing process to stretch the fibers to near the limit of elongation and to set the drawing yarn; Surface treatment: making the drawing yarn pass through a cleaning liquid to remove oil stains and impurities on the surface of the drawing yarn, and then winding it on a water-resistant and corrosion-resistant inner cylinder to form a plating wire cylinder; Initial plating: the initial plating solution is placed in a sealed container, and the wire cylinder to be plated is placed in the initial plating solution for more than 20 minutes. During this period, the sealed container is subjected to varying pressure to change the internal pressure of the initial plating solution, so that the initial plating solution fully contacts and flows with the surface of the drawn wire on the wire cylinder to be plated, and forms a complete and easy-to-plate film on the surface of the drawn wire; Conductive layer plating: the conductive plating solution is placed in a plating tank, and the wire cylinder to be plated is used as the supply cylinder. The drawn wire on the wire cylinder to be plated passes through multiple guide wires in the conductive plating solution in the plating tank in a multiple-turn manner. The speed of the wire is controlled so that each point segment of the drawn wire stays in the conductive plating solution for a time not less than the time required for the thickness of the plated layer. The drawn wire is plated in the conductive layer plating tank through multiple turns, aging and compensation of the plated layer, and forms a plated wire. Post-processing: the plated wire that has walked out of the plating tank passes through a cleaning solution and a drying area, and is then wound onto a wire collecting cylinder to form a bare high-frequency conductor.

[0041] In this embodiment, the high-molecular chemical material can be polyester or polyimide. The material has the characteristic that it can be plated with a conductive metal layer on the surface.

[0042] In applications where the winding framework has isolation grooves, the bare high-frequency conductor can be wound in a single layer in the isolation grooves, and the turns of the winding do not need to be isolated by an insulation layer.

[0043] The benefits of this embodiment are as follows: 1) The core layer of the conductor is made of chemical fibers made of high-molecular chemical materials. Since the density of the chemical fibers is approximately 1-2 g / cm 3 , the densities of copper, silver and gold are 8.96 g / cm 3 , 10.49 g / cm 3 and 19.32 g / cm 3 , respectively, which is more than 5 times the density of the chemical fibers. Therefore, ① the use of chemical fibers as the core layer of the conductor can significantly reduce the weight of the conductor without affecting the high-frequency conductive performance. The higher the frequency of the current carried, the more significant the effect (reason: the higher the frequency, the more significant the skin effect, i.e., the smaller the skin depth, and the thinner the effective surface layer of the conductor for conduction); ② compared to the aluminum core of the copper-clad aluminum conductor in the prior art, the chemical fiber core in this scheme has better flexibility, which can improve the flexibility of the final product (high-frequency conductor) of this scheme; ③ the solid core made of chemical fibers is less likely to deform during winding and bending than hollow conductors (deformation of hollow conductors means non-uniform extension at the deformation site, i.e., the cross-sectional area of the conductor changes abruptly at the deformation site, which affects the uniformity of the impedance and can cause radiation hazards at the site under high-frequency current), and has a certain tensile strength, which is better than that of hollow conductors.

[0044] 2) The chemical fiber used as the core layer is stretched close to the limit of the elongation rate before plating the conductive layer, and is shaped, so that the axial ductility of the chemical fiber is close to the ductility of the plating material, so that the conductive wire after plating can greatly reduce the probability of plating layer breakage and peeling when subjected to external forces such as bending, impact, and extrusion, and ensure the overall conductivity of the entire conductive wire; 3) The thickness of the plating layer is comparable to the skin depth of the corresponding material at the application frequency, so that the plating layer is fully utilized. Since the cost of plating the conductive layer is positively correlated with the thickness of the plating layer, the thickness of the plating layer is comparable to the skin depth of the corresponding material at the application frequency, which is the most economical choice under the premise of optimal conductive performance; 4) In the initial plating process, the entire bobbin is immersed in the plating solution, which can greatly improve the process execution speed, reduce the volume of the initial plating container, and reduce the cost of initial plating. The key is to use a pressure-changing method to drive the initial plating solution to flow between the fiber gaps in the bobbin and squeeze out the air bubbles between them, so that the initial plating solution is in close contact with all the fiber surfaces and flows, achieving the effect of forming a complete, uniform, and easy-to-plate film on the fiber surface, which is beneficial to improving the process execution effect of the subsequent plating of the conductive layer; 5) The plating process of the conductive layer uses multiple turns and controls the wire speed to immerse the stretched wire to be plated in the conductive plating solution, so that each point of the stretched wire to be plated stays in the conductive plating solution for a sufficient time (i.e., each point of the entire stretched wire stays in the conductive plating solution for a sufficient time), so that the conductive particles form a conductive layer on the surface of the stretched wire to be plated. This scheme supports the use of small-size plating tanks to achieve uniform plating of long filaments in a disassembled plating (different from the existing technology of making a bobbin or cloth) manner. The advantages of this scheme are: ① It supports small-size plating tanks, saving process space and cost; ② It uses multiple flow turns to bend and continue plating after bending, so that the plating layer is compensated after experiencing multiple bends (the plating layer has stretching and extrusion), which can greatly strengthen the plating layer and ensure that the final product maintains a complete plating layer and excellent conductive performance in subsequent application winding processes; ③ In the disassembled plating manner, the stretched wire to be plated does not contact and overlap, which can ensure uniform plating of the entire stretched wire and prevent the plating layer thickness from being limited by the intersection points in the existing weaving and plating technology, providing space conditions for thickening the plating layer; ④ By adjusting the wire speed, the residence time of the stretched wire in the plating tank can be adjusted, so that the plating tank thickness can be controlled to adapt to different frequency requirements at the optimal cost.

[0045] In summary, the present scheme creatively proposes a solution to the existing technical problems listed in the background technology, making it possible for chemical fiber conductive fiber (high-frequency conductive wire) to be used in high-frequency current transmission.

[0046] In other embodiments, to facilitate the replacement of existing enameled wire / covered wire by high-frequency conductive wire, the preparation method further includes, based on Embodiment 1: Painting: passing the bare high-frequency wire through a painting device to coat a paint layer on the surface of the bare high-frequency wire; curing: passing the bare high-frequency wire coated with the paint layer through a baking zone or a UV radiation zone to cure the paint layer, and then passing through a cooling zone to cool and set, forming a high-frequency wire with an insulating layer; or Wrapping: using a wrapping yarn process to wrap an insulating yarn on the outer layer of the bare high-frequency wire; or Secondary pre-plating: referring to the initial plating process, plating an easy-to-plate layer on the surface of the bare high-frequency wire; plating an insulating layer: plating a polyester material insulating layer on the easy-to-plate layer on the surface of the bare high-frequency wire in a whole layer, segmented or particle form.

[0047] This embodiment is based on Example 1, and an insulating layer (or insulating point segment) is prepared on the surface of the bare high-frequency wire to form a functionally complete high-frequency wire, so that the finished product directly targets the paint-coated wire of the prior art, is light in weight and high in softness, and has more replaceability. The process of manufacturing an insulating point segment on the surface of the bare high-frequency wire provides a high-frequency wire with a whole layer or segmented or particle form insulating outer layer, i.e., the high-frequency wire has a whole layer insulating layer or local insulation (part of the conductive layer is exposed), and when the local insulation area is greater than the local exposed area, in the subsequent winding process, even if the winding is tightly wound, the local exposed parts of adjacent wires will not contact. That is, this scheme realizes insulation between wires with less insulating layer, which can realize lighter weight and lower cost.

[0048] Example 2 - Multi-directional bending type aging compensation plating layer method As Figure 1 The figure shows the result of the multi-directional folding of the drawn wire to be plated in the conductive layer plating process. In the conductive layer plating process 1, the drawn wire 11 to be plated passes through a flume (not shown) and successively passes through a first horizontal axis wire guide 12, a second horizontal axis wire guide 13, a first vertical axis wire guide 14, and a second vertical axis wire guide 15.

[0049] The first horizontal axis wire guide 12 causes the drawn wire 11 to undergo a horizontal direction bending (first bending); the second horizontal axis wire guide 13 also provides a horizontal direction bending (second bending) to the drawn wire 11, and the bending direction is exactly opposite to the first bending; the first vertical axis wire guide 14 provides a vertical direction bending (third bending) to the drawn wire 11, and the second vertical axis wire guide 15 provides a fourth bending to the drawn wire 11, and the bending direction is opposite to the third bending.

[0050] The aforementioned four bends cause the drawing wire 11 to undergo opposite bends in both horizontal and vertical directions, resulting in four different and mutually perpendicular bending directions. These bends are completed continuously during the wire feeding process, meaning that every point and section of the entire drawing wire 11 undergoes the same treatment. The continuous bending of the drawing wire 11 during the conductive layer plating process induces aging damage to the forming plating layer. Then, it continues to undergo conductive layer plating, with the newly plated conductive layer compensating for and repairing any aging damage that may have occurred during the bending process. Compared to existing static plating techniques, the plating layer, after undergoing multi-directional continuous aging, compensation, and repair, is more robust, wear-resistant, and extrusion-resistant, making it more suitable for carrying current.

[0051] In this embodiment, the number and direction of the guide wires are used to clearly express the technical route of multiple reversals. In specific implementation, it is not limited to horizontal or vertical guide wires, nor is it limited to 4 reversals.

[0052] The advantages of implementing this embodiment are: 1) Multi-directional continuous folding causes the drawing wire to undergo continuous bending in multiple directions, which causes aging damage to the forming coating. Then, during the continued plating process, the coating is compensated and repaired. Actual tests have verified that this can strengthen the coating and make it more suitable for carrying current. 2) The more directions of bending, the more complete the aging, compensation and repair of the coating, and the better the strength of the entire coating of the high-frequency conductor, making it more suitable for current transmission applications.

[0053] Example 3 – A High-Efficiency Method for Supporting Multiple Drawing Wires to Enter the Plating Bath Simultaneously Figure 2 The diagram illustrates the structure of a wire guide with three wire guide ports. The wire guide 2 includes a common base 21, three wire guide hooks 22, a first wire guide cavity 23, a second wire guide cavity 24, a third wire guide cavity 25, a first wire guide port 26, a second wire guide port 27, a third wire guide port 28, a fixing foot 20, and a fixing hole 29.

[0054] In this embodiment, Figure 2 The multiple wire guides 2 shown are fixed in the plating tank (not shown) at the required angles for multiple wire guides, guiding the drawn wire through the plating tank. In use, the drawn wire is entered into the respective wire guide cavities (23, 24, 25) through each wire guide opening (26, 27, 28), and each wire guide cavity (23, 24, 25) constrains the drawn wire to move within a predetermined range. Since each wire guide 2 has three wire guide openings (26, 27, 28), 1) It can support three drawing wires to be guided by multiple wire guides 2 at the same time, so that the three drawing wires can run parallel through the plating tank. ① This avoids the situation where the drawing wires of each segment need to overlap and cross each other in the weaving plating technology; ② It allows multiple drawing wires to move in the plating tank without obstruction and complete the process of plating the conductive layer. Under the premise of ensuring the quality of the plating layer, the space of the plating tank can be fully utilized and the process efficiency can be improved. 2) It can also be used to fold the same drawing wire back and forth more times in the plating bath. Under the same wire feeding speed, a smaller plating bath space can be used to complete the process of plating a conductive layer.

[0055] In this embodiment, the guide wire device 2 is provided with no more than 3 guide wire ports and guide wire cavities, and can be increased or decreased as needed.

[0056] Example 4 – High-frequency conductors with increased current density, using single-strand round-square or oblong-square cross-sections. like Figure 3 As shown, in the core-making process, by designing the shape of the spinneret holes on the spinneret of the spinning process, the cross-section of the spun drawn yarn is made into a round square or an oblong square, which supports the final high-frequency conductor 3 to be made into a round square (rounded square) cross-section. Among them, the core layer 31 of the high-frequency conductor 3 is round square and is made of insulating polyester or polyimide material; the conductive layer 32 is generated by the conductive layer plating process and is made of conductive material; the insulating layer 33 is a varnish layer or a yarn layer and is insulating.

[0057] Compared to the commonly used enameled wire with a circular cross-section, the high-frequency conductor 3 produced in this embodiment has a larger surface area under the premise that the side length is equal to the diameter, and the conductive layer can carry a larger current; when it is wound into a winding, space can be fully utilized to improve current density and power density.

[0058] Example 5 – High-frequency conductor with integrated strand to improve current density like Figure 4 As shown, the integrated stranded high-frequency conductor 4 has a core layer composed of a first core 41 and a second core 42 connected together by a reinforcing rib 43. This structure is formed by a one-time spinning process. The outer wall of the core layer is plated with a conductive layer 44, and the outer wall of the conductive layer 44 is provided with an insulating layer 45. Compared with the single-strand round-square and oblong-square cross-section high-frequency conductors of Embodiment 4, the stranded high-frequency conductor of this embodiment has a larger surface area under the premise of the same cross-sectional area, that is, the cross-sectional area of ​​the conductive layer is larger, and the current density and power density are higher.

[0059] Comparing the present embodiment with embodiment 4, the present embodiment is equivalent to adding the groove 46 on the basis of the oblong square cross section of embodiment 4. Thus, in other embodiments, the same principle as embodiment 5 is used to provide grooves or protrusions on the outer edge of the cross section of the core layer, thereby changing the outer edge of the cross section from a straight line to a curved line, increasing the cross-sectional area of the cross section and the cross-sectional area of the conductive layer 44, and improving the current density and power density.

[0060] Embodiment 6 - High-frequency wire with integrated insulation layer In the core-making process, the spinning process is composite spinning, and the cross section of the drawn wire is designed to be Figure 5 , (this embodiment takes a circular cross section as an example), in which, as shown in Figure 5 , the drawn wire 5 is integrally composed of a core layer 51, three intermediate layers 52, and three shell layers 53, the core layer 51 and each shell layer 53 are connected by connecting ribs 54 (which are made of the same material as the core layer 51 or the shell layer 53, and preferably the same material as the core layer 51), and on each shell layer 53, there is a protruding window 55 corresponding to the intermediate layer 52, which is made of the same material as the intermediate layer 52. Among them: The intermediate layer 52 is soluble in a liquid solvent; The core layer 51 can be plated with a conductive layer, but is not soluble in a liquid solvent that can dissolve the intermediate layer 52; The shell layer 53 cannot be plated with a conductive layer and is not soluble in a liquid solvent that can dissolve the intermediate layer 52.

[0061] In the process of making high-frequency wire, the drawn wire shown in Figure 5 is placed in a liquid solvent that can dissolve the intermediate layer 52 for a period of time, so that the soluble intermediate layer 52 is completely dissolved in the solvent, leaving the insoluble core layer 51 and shell layer 53, forming a skeleton structure as shown in Figure 6 , that is, the treated drawn wire 5A is integrally formed by the core layer 51 and the shell layer 53, between the core layer 51 and the shell layer 53, the original intermediate layer 52 is dissolved to form three cavities 57, and on the shell layer 53, the protruding window 55 of the original intermediate layer 52 is dissolved to form an opening 57, which is in communication with the cavity 57.

[0062] In subsequent processes, the surface treatment, initial plating, and conductive layer plating processes described in embodiment 1 are performed, and the cleaning liquid, initial plating liquid, and conductive plating liquid used in the corresponding processes can all enter the cavity 57 through the opening 57 to treat the inner surface of the cavity 57. Since the core layer 51 can be plated with a conductive layer and the shell layer 53 cannot be plated, a plating layer (not shown) is finally formed on the platable surface 58 of the cavity 57. After the post-processing process, the entire process is completed, and the high-frequency wire is made.

[0063] The high frequency wire made by the embodiment has a non-conductive chemical fiber core, a conductive plating layer in the middle, and an insulating shell layer on the outside, which has the characteristics of enameled wire and cotton-covered wire and meets the needs of high frequency current transmission. Since the core layer and the shell layer are formed integrally in the core making process and no insulating layer coating, plating, winding and other processes are needed after the conductive layer is plated, the operation process of the plating layer is reduced, the damage to the plating layer is greatly reduced, the production efficiency is improved, and the product quality is improved.

[0064] In other embodiments, the technologies of embodiments 2, 3, 4, and 5 are introduced into the high frequency wire making technology of one-time forming an insulating layer, which can harvest the benefits of embodiments 2, 3, 4, and 5 on the basis of the benefits of the present embodiment.

[0065] The above describes specific embodiments of the present specification, and other embodiments are within the scope of the appended claims. In some cases, the structures and methods described in the claims can refer to the above-described specific embodiments to achieve the desired results. Those skilled in the art can easily achieve the desired results by referring to the above-described specific embodiments and their design ideas.

[0066] The above only describes one or more embodiments of the present specification and does not limit the present specification. Those skilled in the art can implement new embodiments by new combinations of the technical solutions of one or more embodiments of the present specification, or can make various modifications and changes. Any modifications, equivalent replacements, improvements, technical combinations, etc. within the spirit and principles of one or more embodiments of the present specification shall be included in the scope of the claims of the present specification.

Claims

1. A high-frequency wire and a preparation method thereof, characterized in that, the high-frequency wire is of a multi-layer structure, the core layer of which is chemical fiber stretched to near the ultimate tensile ratio and shaped, and the surface of which is plated with a copper-based and / or carbon-based and / or silver-based and / or gold-based conductive layer; the thickness of the conductive layer is equivalent to the skin depth of the corresponding material at the application frequency; the preparation method comprises: core preparation: selecting a high-molecular compound material, using a spinning process to make fiber, and using a drawing process to stretch the fiber to near the ultimate tensile ratio and shape it into drawn yarn; surface treatment: making the drawn yarn pass through a cleaning solution to remove oil stains and impurities on the surface of the drawn yarn, and then winding it onto a water-resistant and corrosion-resistant inner cylinder to form a plating cylinder; primary plating: placing the primary plating solution in a sealed container, placing the plating cylinder in the primary plating solution for more than 20 minutes, and applying varying pressure to the sealed container to change the internal pressure of the primary plating solution, so that the primary plating solution fully contacts and flows with the surface of the drawn yarn on the plating cylinder and forms a complete and easy-to-plate film on the surface of the drawn yarn; plating a conductive layer: placing the conductive plating solution in a plating tank, using the plating cylinder as a supply cylinder, and making the drawn yarn on the plating cylinder pass through multiple guide rollers in a multiple-turn manner to flow through the conductive plating solution in the plating tank, controlling the wire speed so that each point of the drawn yarn stays in the conductive plating solution for no less than the time required for plating thickness, and repeatedly turning, aging, and compensating the plating layer to form a plated wire; post-processing: making the plated wire pass through a cleaning solution and a drying area after leaving the plating tank, winding it onto a wire collecting cylinder, and producing a bare high-frequency wire.

2. A high frequency conductor according to claim 1, characterized in that The high-molecular compound material is made of polyester or polyimide.

3. A high frequency conductor according to claim 1, characterized in that In addition to the conductive layer, an insulating paint layer is also coated on the conductive layer; Correspondingly, the preparation method further comprises: painting: making the bare high-frequency wire pass through a painting device to coat a paint layer on the surface of the bare high-frequency wire; curing: making the bare high-frequency wire with the paint layer pass through a baking area or a UV radiation area to cure the paint layer, and then passing through a cooling area to cool and shape it, forming a high-frequency wire with an insulating layer; winding: winding the high-frequency wire with the insulating layer onto a wire cylinder.

4. A high frequency conductor according to claim 1, characterized in that In addition to the conductive layer, an insulating yarn is also wound around the conductive layer; Correspondingly, the preparation method further comprises: yarn covering: using a covering yarn process to cover the insulating yarn on the outer layer of the bare high-frequency wire; winding: winding the high-frequency wire with the insulating layer onto a wire cylinder.

5. A high frequency conductor according to claim 1, characterized in that In addition to the conductive layer, a non-conductive layer and / or non-conductive particles and / or non-conductive rings are also plated on the conductive layer; Correspondingly, the preparation method further comprises: secondary pre-plating: referring to the primary plating process, plating an easy-to-plate layer on the surface of the bare high-frequency wire; plating an insulating layer: plating an insulating layer made of polyester material on the easy-to-plate layer on the surface of the bare high-frequency wire in a whole layer, segmented, or particle form.

6. A high frequency conductor according to claim 1, characterized in that The guide direction of the multiple guide rollers guides the drawn yarn to produce multiple directional bends, so that the whole drawn yarn continues to be plated after multiple directional bends in the process of plating the conductive layer, that is, bending during plating and continuing to plate after bending, which can continuously compensate and repair the impact of bending on the plated layer, thereby strengthening the strength of the plated layer.

7. A high frequency conductor according to claim 1, characterized in that The guide roller is of a multi-guide port structure, supporting multiple drawn yarns to be plated simultaneously, and the multiple drawn yarns do not come into contact with each other.

8. A high frequency conductor according to claim 1, characterized in that The plating tank is provided with a fluid propulsion mechanism, which runs at low speed or intermittently to push the plating solution in the plating tank to flow slowly or intermittently, thereby increasing the growth speed and uniformity of the plating layer.

9. A high frequency conductor according to claim 1, characterized in that The shape of the cross section of the core layer is circular square or long circular square, which can increase the wire surface area of the high-frequency wire under a given winding space, that is, when the high-frequency wire is wound on a skeleton to form a winding in subsequent applications, the winding space can be fully utilized to increase the current density and power density; correspondingly, the spinning hole of the spinning plate is made into a circular square or a long circular square in the spinning process.

10. A high frequency conductor according to claim 1, characterized in that The drawn yarn made by the core-making process has a cross section including a core layer, an intermediate layer and a shell layer, which are all spinnable high molecular materials, wherein: the core layer and the shell layer are connected by at least one connecting rib, most of the intermediate layer is embedded between the core layer and the shell layer, and the intermediate layer wraps the other part of the core layer except the connecting rib, and on the shell layer, there is a protruding window of the intermediate layer; The intermediate layer is soluble in a liquid solvent; The core layer can be plated with a conductive layer, but cannot be dissolved in a liquid solvent that can dissolve the intermediate layer; The shell layer cannot be plated with a conductive layer and cannot be dissolved in a liquid solvent that can dissolve the intermediate layer; Correspondingly, the preparation method further includes: In the core-making process, the spinning process is a composite spinning process, which forms the same fiber by molding the molten core layer, intermediate layer and shell layer material through the same spinning hole at one time. Dissolution: the drawn yarn made by the core-making process is placed in a solvent that can dissolve the intermediate layer, so that the intermediate layer in the drawn yarn is dissolved in the solvent, and this process is performed between the core-making process and the surface treatment process.

11. A high frequency conductor according to claim 1, characterized in that The cross section of the drawn yarn made by the core-making process is a multi-strand connected type, that is, a plurality of strands are connected by ribs to form a whole, and / or the axial surface of the drawn yarn is provided with grooves to increase the surface area, thereby increasing the cross-sectional area of the plating layer and increasing the load flow.

Images