Data transmission line and double glue injection port extrusion die

Abstract

This application relates to a data transmission line and a dual-nozzle extrusion die. A foamed insulation layer is formed in a single co-extrusion process and covers the first and second conductors, with the first and second conductors separated by the foamed insulation layer. An outer sheath layer covers the foamed insulation layer. In a cross-section along the length of the data transmission line, the data transmission line has an axis of symmetry. The first and second conductors are axially symmetrical with respect to this axis, as are the foamed insulation layer and the outer sheath layer. This forms a dual-conductor single-stage foamed co-extrusion structure, ensuring that the foaming degree and concentricity of the outer insulation of the two conductors are consistent, thus guaranteeing the symmetry between the differential pairs in principle. It overcomes the technical bias of having to produce the core wires separately first, by incorporating the foamed insulation of the core wires as part of the foamed insulation layer, saving processes, improving production efficiency, and ensuring the symmetry of the core wires.

Description

Technical Field

[0001] This application relates to the field of communication cables, and in particular to data transmission lines and dual-nozzle extrusion molds. Background Technology

[0002] With the rapid development of the digital economy and communication technologies, the commercialization of 5G / 6G, the upgrading of computing power in high-speed data centers, and the intelligentization of the industrial internet have led to an explosive growth in demand for high-speed differential signal transmission cables. As the core carrier of differential signal transmission, the structural symmetry of the insulation layer and the dielectric constant of the material directly determine the key electrical performance of differential transmission, such as common-mode rejection ratio, latency, and transmission attenuation. High-frequency, high-speed differential signals place stringent requirements on the transmission medium, requiring the insulation layer to possess low dielectric constant, low dielectric loss, capacitance consistency, and structural symmetry. Traditional solid insulation layers, due to their high dielectric constant and large attenuation, can no longer meet the low-loss transmission requirements of high-frequency bands.

[0003] Traditional data cables have two symmetrical cores in a differential pair. Each core consists of a conductor covered with an insulating medium. To reduce overall cable attenuation, a common practice is to use a low-dielectric-constant foamed material as the insulating medium for each core. Then, an inner sheath is wrapped around the two foamed cores, followed by a shielding layer and an outer sheath to form a complete differential signal pair. A cross-sectional view of a traditional data cable along its length is shown below. Figure 1 As shown, the differential pair has two symmetrical core wires 110. Each core wire 110 includes a conductor 111 and a foamed insulator 112 covering the conductor 111. The foamed insulator 112 of the two core wires 110 is completely covered by an inner insulating layer 120. The inner insulating layer 120 is covered by a metal shielding layer 130. Two symmetrical ground wires 140 are provided outside the metal shielding layer 130, and an outer sheath 150 completely covers the metal shielding layer 130 and the two ground wires 140.

[0004] However, the data lines and their differential pairs obtained in actual production have the following problems.

[0005] First, there is a problem with the symmetry: In actual production, since the two core wires are made separately, that is, two single-core foamed core wires need to be produced, it is basically impossible to make their foaming degree and concentricity completely consistent, resulting in a problem with the symmetry between the differential wire pairs, which affects the quality of differential signal transmission.

[0006] Secondly, the strength is poor: because the foam material of the single-core foamed wire is filled with a large number of micropores, it will deform when subjected to force. When the single-core foamed wire needs to be processed later, whether it is an extruded inner liner or a tape-type inner liner, including the subsequent covering shielding layer and outer liner, it is easy to deform and be damaged during the process of passing through the guide roller or wrapping. Therefore, the operation space of its subsequent processes is small and the fault tolerance rate is low. Summary of the Invention

[0007] Therefore, it is necessary to provide a data transmission line and a dual-nozzle extrusion mold.

[0008] One embodiment of this application is a data transmission line, which includes a first conductor, a second conductor, a foamed insulating layer, and an outer sheath;

[0009] The foamed insulating layer is formed by one co-extrusion and covers the first conductor and the second conductor, and the first conductor and the second conductor are separated by the foamed insulating layer;

[0010] The outer skin layer covers the foamed insulation layer;

[0011] In a cross-section along the length of the data transmission line, the data transmission line has an axis of symmetry. The first conductor and the second conductor are arranged symmetrically with respect to the axis of symmetry. The foamed insulation layer itself is arranged symmetrically with respect to the axis of symmetry. The outer skin layer itself is arranged symmetrically with respect to the axis of symmetry.

[0012] The aforementioned data transmission line, through the cooperation of a first conductor, a second conductor, a foamed insulation layer, and an outer sheath, forms a dual-conductor, single-stage foamed co-extrusion structure. Encapsulating both conductors with foamed material in a single process ensures consistent foaming degree and concentricity of the outer insulation, thus guaranteeing the symmetry between the differential pairs in principle. Furthermore, it overcomes the technical bias of requiring separate production of the core wires, integrating the core wire's foamed insulation as part of the foamed insulation layer, forming it in a single co-extrusion process and encapsulating it around the first and second conductors. This saves on processes and improves production efficiency. This design maximizes the symmetry of the core wires, achieving two goals at once. Furthermore, the foamed insulation layer is a single unit, avoiding the two-layer design of the foamed insulation body and inner insulation layer found in traditional data cables. This improves the overall mechanical strength of the data transmission line, ensuring symmetry between differential pairs while significantly enhancing the overall mechanical strength and bending resistance. Additionally, the overall manufacturing process of the data transmission line is simple, eliminating the need for further processing of the single-core foamed wires. This fundamentally overcomes the problem of deformation and damage to the single-core foamed wires during guide wheel or wrapping processes, thus facilitating production.

[0013] In some embodiments, the foamed insulation layer includes a first inner skin layer, a second inner skin layer, and a foamed layer formed by a single co-extrusion process;

[0014] The first endothelial layer covers the first conductor, the second endothelial layer covers the second conductor, and the foam layer covers both the first and second endothelial layers, with the first and second endothelial layers separated by the foam layer.

[0015] As an example, the foamed insulation layer is formed by condensation to form the first inner skin layer and the second inner skin layer.

[0016] As an example, the thickness of the first inner skin layer is set by the temperature of the first conductor, the thickness of the second inner skin layer is set by the temperature of the second conductor, and the temperature of the first conductor is the same as the temperature of the second conductor.

[0017] In some embodiments, the first endothelial layer and the second endothelial layer have the same thickness and are no greater than 1 mm.

[0018] In some embodiments, the foamed insulation layer has a semi-closed or fully closed microporous structure formed by gas-filling foaming, and the microporous structure is filled with a preset gas.

[0019] As an example, the fully enclosed microporous structure means that each of the microporous structures is not interconnected; the semi-enclosed microporous structure means that at least two of the microporous structures are interconnected. As an example, the preset gas includes nitrogen, carbon dioxide, and inert gas.

[0020] In some embodiments, the foaming degree of the foamed insulation layer is not less than 20%; or,

[0021] The outer skin layer thickness is not less than 0.01 mm; or,

[0022] In the cross-section, the foamed insulation layer and the outer skin layer together form an outward protrusion, and the outward protrusion itself is arranged axially symmetrically with respect to the axis of symmetry.

[0023] For an embodiment with a foamed layer, as an example, the degree of foaming of the foamed layer is not less than 20%.

[0024] In some embodiments, the outer skin layer and the foamed insulation layer are co-extruded together in a single process and cover the first conductor and the second conductor.

[0025] In some embodiments, the data transmission line further includes a shielding layer that covers the outer sheath.

[0026] In some embodiments, the first conductor and the second conductor have a first distance along the direction of the center line connecting the center of the first conductor and the second conductor, and either the first conductor or the second conductor has a second distance from the shielding layer;

[0027] In the direction of the axis of symmetry, either the first conductor or the second conductor has a third distance from the shielding layer;

[0028] The first distance is not greater than the second distance; or,

[0029] The first distance is not greater than the third distance; or,

[0030] The second distance is equal to the third distance.

[0031] As an example, the data transmission line further includes a first ground wire and a second ground wire arranged symmetrically with respect to the axis of symmetry. The first ground wire and the second ground wire are located within the shielding layer and in contact with the shielding layer, and are co-extruded with the foamed insulation layer.

[0032] In some embodiments, the data transmission line further includes a first ground wire, a second ground wire, and a protective layer;

[0033] The first ground wire and the second ground wire are arranged symmetrically with respect to the axis of symmetry and are located outside the shielding layer;

[0034] The protective layer covers the shielding layer, the first ground wire, and the second ground wire, and the protective layer itself is arranged symmetrically with respect to the axis of symmetry.

[0035] In some embodiments, a dual-nozzle extrusion die is configured to prepare the data transmission line described in any embodiment;

[0036] The dual-injection-gate extrusion mold includes an inner mold and an outer mold arranged coaxially, and the inner mold is provided with a foam material injection port and an outer skin material injection port. Attached Figure Description

[0037] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 This is a cross-sectional view of a traditional data cable along its length.

[0039] Figure 2 This is a schematic diagram of the structure of the first embodiment of the data transmission line described in this application.

[0040] Figure 3 for Figure 2 A schematic cross-sectional view along the AA direction of the embodiment shown.

[0041] Figure 4 This is a cross-sectional schematic diagram of a second embodiment of the data transmission line described in this application.

[0042] Figure 5 for Figure 4 Another schematic diagram of the embodiment shown.

[0043] Figure 6 This is a cross-sectional schematic diagram of the third embodiment of the data transmission line described in this application.

[0044] Figure 7 This is a cross-sectional schematic diagram of the fourth embodiment of the data transmission line described in this application.

[0045] Figure 8 This is a cross-sectional schematic diagram of the fifth embodiment of the data transmission line described in this application.

[0046] Figure 9 This is a structural cross-sectional schematic diagram of an embodiment of the dual injection nozzle extrusion die described in this application.

[0047] Figure 10 for Figure 9 The illustrated embodiment is shown in the following diagram.

[0048] Reference numerals: Core wire 110, Conductor 111, Foamed insulator 112, Inner insulating layer 120, Metal shielding layer 130, Ground wire 140, Outer sheath layer 150, Data transmission line 200, First distance 201, Second distance 202, Third distance 203, Center connection direction 204, First conductor 210, Second conductor 220, Foamed insulating layer 230, First inner sheath layer 231, Second inner sheath layer 232, Foamed layer 233, Outer sheath layer 240, Shielding layer 250, Length direction 260, First ground wire 261, Second ground wire 262, Protective layer 270, Axis of symmetry 280, Outer protrusion 290, Double injection nozzle extrusion mold 300, Inner mold 310, Outer mold 320, Foamed material injection nozzle 330, Outer sheath material injection nozzle 340. Detailed Implementation

[0049] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0050] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on the other component or there may be an intermediate component. When a component is considered to be "connected to" another component, it can be directly connected to the other component or there may be an intermediate component present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application's specification are for illustrative purposes only and do not represent the only possible implementation.

[0051] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0052] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature and the second feature are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0053] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and or" as used in this application includes any and all combinations of one or more of the associated listed items.

[0054] In one embodiment of this application, a data transmission line includes a first conductor, a second conductor, a foamed insulating layer, and an outer sheath layer. The foamed insulating layer is formed by a single co-extrusion process and covers the first conductor and the second conductor, with the first conductor and the second conductor spaced apart by the foamed insulating layer. The outer sheath layer covers the foamed insulating layer. In a cross-section along the length direction of the data transmission line, the data transmission line has an axis of symmetry, with the first conductor and the second conductor arranged axially symmetrically with respect to the axis of symmetry, the foamed insulating layer itself arranged axially symmetrically with respect to the axis of symmetry, and the outer sheath layer itself arranged axially symmetrically with respect to the axis of symmetry. The aforementioned data transmission line, through the cooperation of a first conductor, a second conductor, a foamed insulation layer, and an outer sheath, forms a dual-conductor, single-stage foamed co-extrusion structure. Encapsulating both conductors with foamed material in a single process ensures consistent foaming degree and concentricity of the outer insulation, thus guaranteeing the symmetry between the differential pairs in principle. Furthermore, it overcomes the technical bias of requiring separate production of the core wires, integrating the core wire's foamed insulation as part of the foamed insulation layer, forming it in a single co-extrusion process and encapsulating it around the first and second conductors. This saves on processes and improves production efficiency. This design maximizes the symmetry of the core wires, achieving two goals at once. Furthermore, the foamed insulation layer is a single unit, avoiding the two-layer design of the foamed insulation body and inner insulation layer found in traditional data cables. This improves the overall mechanical strength of the data transmission cable, ensuring symmetry between differential pairs while significantly enhancing the overall mechanical strength and bending resistance. Additionally, the overall manufacturing process of the data transmission cable is simple, eliminating the need for further processing of the single-core foamed wires. This fundamentally overcomes the problem of deformation and damage to the single-core foamed wires during guide wheel or wrapping processes, thus facilitating production. The following section will combine... Figures 1 to 10 The data transmission line and the dual-nozzle extrusion mold are described in detail.

[0055] In some embodiments, a data transmission line 200, such as Figure 2 and Figure 3As shown, it includes a first conductor 210, a second conductor 220, a foamed insulating layer 230, and an outer skin layer 240. The foamed insulating layer 230 is formed by co-extrusion and covers the first conductor 210 and the second conductor 220, and the first conductor 210 and the second conductor 220 are spaced apart by the foamed insulating layer 230. The outer skin layer 240 covers the foamed insulating layer 230. In the cross-section along the length direction 260 of the data transmission line 200, the data transmission line 200 has an axis of symmetry 280. The first conductor 210 and the second conductor 220 are axially symmetrical with respect to the axis of symmetry 280. The foamed insulating layer 230 itself is axially symmetrical with respect to the axis of symmetry 280, and the outer skin layer 240 itself is axially symmetrical with respect to the axis of symmetry 280.

[0056] This structural design, through the cooperation of the first conductor 210, the second conductor 220, the foamed insulation layer 230, and the outer sheath layer 240, forms a dual-conductor one-time foamed co-extrusion structure. By encapsulating the two conductors with foamed material in a single process, it ensures that the foaming degree and concentricity of the outer insulation of the two conductors are consistent, thus guaranteeing the symmetry between the differential pairs in principle. Furthermore, it overcomes the technical bias of requiring separate production of the core wires. The foamed insulation of the core wire is incorporated as part of the foamed insulation layer 230, formed in a single co-extrusion process and encapsulated on the first conductor 210 and the second conductor 220, saving processes and improving efficiency. This design achieves two goals at once: improving production efficiency and ensuring the symmetry of the core wires. Furthermore, the foamed insulation layer 230 is a single unit, avoiding the two-layer design of the foamed insulation and inner insulation layer found in traditional data cables. This improves the overall mechanical strength of the data transmission line 200, ensuring symmetry between differential pairs and significantly enhancing the overall mechanical strength and bending resistance. Additionally, the overall process of the data transmission line 200 is simple, eliminating the need for further processing of the single-core foamed wires. This fundamentally overcomes the problem of deformation and damage to the single-core foamed wires during guide wheel or wrapping processes, thus facilitating production.

[0057] In each embodiment, the conductor includes the first conductor 210 and the second conductor 220. A portion of the data transmission line 200 structure is obtained by co-extruding the two conductors together with the material of the foamed insulating layer 230. The number of conductors is two, composed of single or multiple strands of metal wire. The conductor material includes, but is not limited to, silver-plated copper, tin-plated copper, bare copper, silver-plated copper-clad steel, and silver-plated copper-clad aluminum. The shape of the conductor in cross-section can be any of the following: circular, elliptical, flat, or other shapes.

[0058] This design, on the one hand, clearly defines the two conductors, the first conductor 210 and the second conductor 220, and co-extrudes the data transmission line 200 with the foamed insulation layer 230 material. It allows for flexible selection of single or multi-strand metal wires and various conductor materials such as silver-plated copper and tin-plated copper to adapt to different transmission scenarios and performance requirements, balancing conductivity and cost. On the other hand, the conductor cross-section can be selected in various shapes such as circular and elliptical. With the one-time co-extrusion of the foamed insulation layer 230, the coverage space of the foamed insulation layer 230 can be precisely matched to ensure that the spacing between the first conductor 210 and the second conductor 220 is uniform and stable. Furthermore, it simplifies the conductor material selection and molding adaptation process, eliminating the need for additional adjustments to adapt to different conductor specifications, improving production versatility and efficiency, while ensuring the differential transmission stability and structural adaptability of the data transmission line 200.

[0059] In each embodiment, such as Figure 3 As shown, the foamed insulation layer 230 is formed by a single co-extrusion process and covers the first conductor 210 and the second conductor 220. The first conductor 210 and the second conductor 220 are separated by the foamed insulation layer 230. By employing a dual-conductor single-stage foamed co-extrusion structure, the two conductors are simultaneously covered with foamed material, ensuring the symmetry between the differential pairs and significantly improving the overall mechanical strength and bending resistance of the line. In some embodiments, the foamed insulation layer 230 forms a semi-closed or fully closed microporous structure through a gas-filled foaming process, and the microporous structure is filled with a preset gas. For example, a fully closed microporous structure means that each microporous structure is not interconnected; a semi-closed microporous structure means that at least two microporous structures are interconnected. For example, the preset gas includes nitrogen, carbon dioxide, and an inert gas. In some embodiments, the degree of foaming of the foamed insulation layer 230 is not less than 20%; for embodiments having a foamed layer 233, as an example, the degree of foaming of the foamed layer 233 is not less than 20%.

[0060] This structural design, on the one hand, employs a one-time co-extrusion molding of the foamed insulation layer 230 to cover the first conductor 210 and the second conductor 220, ensuring that the two conductors are evenly spaced by the foamed insulation layer 230, thus guaranteeing the symmetry of the differential pair from the structural source and effectively reducing signal transmission loss and crosstalk. On the other hand, by inflating and foaming to form a semi-closed or fully closed microporous structure, with the micropores filled with preset gases such as nitrogen, carbon dioxide, and inert gases, the dielectric constant of the foamed insulation layer 230 can be significantly reduced, improving the stability of high-frequency signal transmission. Furthermore, limiting the foaming degree of the foamed insulation layer 230 and the foamed layer 233 to no less than 20% not only reduces the overall weight of the data transmission line 200 but also enhances the buffering and bending resistance of the foamed insulation layer 230, further improving the mechanical strength of the entire line. Moreover, the microporous structure design optimizes the overall toughness of the foamed insulation layer 230, effectively avoiding the problem of easy cracking of traditional foamed layers, thereby extending the service life of the data transmission line 200, while also simplifying the foaming process and helping to ensure production consistency.

[0061] As an example, the foamed insulation layer 230 is entirely wrapped around the two conductors and co-extruded in one step. Its overall shape is elliptical or near-elliptical. The materials of the foamed insulation layer 230 include, but are not limited to, foamed polyethylene (PE), foamed polypropylene (PP), foamed polystyrene (PS), foamed polyethylene terephthalate (PET), foamed polyphenylene ether (PPO), foamed polytetrafluoroethylene (PTFE), foamed fluoroethylene propylene (FEP), and foamed perfluoroalkoxy alkane (PFA). The interior of the foamed insulation layer 230 is filled with a large number of micropores. Each micropore is semi-closed or fully closed, meaning that micropores on adjacent cross-sections are not interconnected. The micropores are filled with gas, such as nitrogen, helium, or other inert gases, and the foaming degree is greater than or equal to 20%.

[0062] This structural design has several advantages. First, the foamed insulation layer 230 is co-extruded to cover two conductors in a single process, resulting in an elliptical or near-elliptical shape with a regular and symmetrical appearance. This facilitates uniform coverage by the outer sheath layer 240, ensuring the overall structural stability of the data transmission line 200. Second, the foamed insulation layer 230 uses various low-dielectric materials such as foamed polyethylene (PE) and foamed polypropylene (PP) to adapt to different high-frequency transmission scenarios, effectively reducing signal transmission loss. Third, the foamed insulation layer 230 is densely packed with semi-closed or fully closed micropores filled with nitrogen, helium, or other inert gases, with a foaming degree of ≥20%. This significantly reduces the dielectric constant of the insulation layer, increases the signal transmission rate, and reduces the weight of the line. Fourth, the interconnected structure of the micropores helps prevent gas loss, stabilizes insulation performance, and enhances the bending and aging resistance of the foamed insulation layer 230, thereby effectively extending the service life of the data transmission line 200.

[0063] contrast Figure 1 Traditional data cables have an insulating inner sheath outside the core wire 110. This can be understood as the core wire 110 having a first insulating medium, namely the foamed insulator 112 outside the conductor 111, while the core wire 110 has a second insulating medium outside, used to adjust the coupling ratio between the conductors 111. Since it is a two-stage manufacturing process, there will be a problem with the bonding strength. In contrast, the data transmission line 200 described in this application can be understood as a dual-conductor one-time foamed co-extrusion structure, which covers the two conductors with foamed material in one go, which can not only ensure the symmetry between the differential pairs, but also greatly improve the mechanical strength and bending resistance of the entire line. In various embodiments, the foamed insulating layer 230 uses the same material before extrusion, but its morphology changes after extrusion due to contact with the conductor. In some embodiments, the foamed insulating layer 230 includes a first inner skin layer 231, a second inner skin layer 232, and a foamed layer 233 formed by a single co-extrusion process; the first inner skin layer 231 covers the first conductor 210, the second inner skin layer 232 covers the second conductor 220, and the foamed layer 233 covers the first inner skin layer 231 and the second inner skin layer 232, with the first inner skin layer 231 and the second inner skin layer 232 separated by the foamed layer 233.

[0064] This structural design, on the one hand, abandons the traditional double-layer insulation structure of adding an inner sheath to the core wire 110 of the data cable, overcoming the defects of insufficient bonding strength and easy peeling between layers caused by the two-stage preparation of the traditional process, fundamentally solving the problem of delamination between the first and second insulation media, and significantly improving the overall structural stability of the data transmission line 200; on the other hand, it adopts a dual-conductor one-time foaming co-extrusion structure, covering the first conductor 210 and the second conductor 220 with foaming material in one go, ensuring the symmetry of the differential wire pairs from the source of the process, avoiding conductor offset and uneven spacing caused by step processing, and greatly improving the mechanical strength and bending resistance of the entire line; furthermore, the foamed insulation layer 230 has consistent material and differentiated morphology before and after extrusion, forming the first inner sheath layer 231, the second inner sheath layer 232 and the foaming layer 233 in one piece, with the inner sheath layer precisely adhering to the conductor and the foaming layer firmly separating the two conductors, taking into account both insulation protection and differential isolation effects; and on the other hand, it helps to simplify the production process, eliminating the need for additional processing of the inner sheath layer, reducing process errors, thereby effectively improving production efficiency and product consistency, and reducing manufacturing costs.

[0065] To save on extruder head space and improve the adhesion of the foamed insulation layer 230, as an example, the foamed insulation layer 230 is formed by condensation to create the first inner skin layer 231 and the second inner skin layer 232. The thickness of the first inner skin layer 231 and the second inner skin layer 232 can be easily controlled or adjusted by setting the condensation temperature. As an example, the thickness of the first inner skin layer 231 is set by the temperature of the first conductor 210, and the thickness of the second inner skin layer 232 is set by the temperature of the second conductor 220, with the temperatures of the first conductor 210 and the second conductor 220 being the same. For symmetry considerations, in some embodiments, the thickness of the first inner skin layer 231 and the second inner skin layer 232 are the same and not greater than 1 mm. As an example, the inner skin layer thickness is less than 1 mm, and its thickness is controlled by conductor pre-cooling to control the degree of condensation of the foamed material. The conductor pre-cooling temperature is not higher than 40°C, and the conductor acts as a condenser relative to the high-temperature liquid foamed insulation layer 230. As an example, the pre-cooling temperature of the conductor is not higher than 40°C; or, the pre-cooling temperature of the conductor is not higher than 30°C.

[0066] This structural design, on the one hand, allows the foamed insulation layer 230 to directly form the first inner skin layer 231 and the second inner skin layer 232 through condensation, eliminating the need for an additional extruder head, simplifying equipment configuration, reducing investment costs, and simultaneously improving the adhesion between the foamed insulation layer 230 and the first conductor 210 and the second conductor 220, avoiding the risk of interlayer delamination and enhancing structural reliability; on the other hand, the thickness of the first inner skin layer 231 and the second inner skin layer 232 can be precisely controlled by the condensation temperature, and with the same temperature control of the first conductor 210 and the second conductor 220, the thickness of the two inner skin layers is guaranteed to be consistent. This effectively avoids differential impedance imbalance and signal crosstalk issues, ensuring symmetrical and stable electrical performance. On the other hand, the thickness of the inner skin layer is limited to no more than 1 mm. Combined with a conductor pre-cooling process at no more than 40°C, the temperature difference between the high-temperature foaming material and the low-temperature conductor is used to achieve condensation and shaping, eliminating the need for additional cooling devices. This simplifies the process, shortens the molding cycle, and improves production efficiency. Furthermore, the two inner skin layers and the foaming layer 233 are integrally molded from the same source, eliminating the risk of interface delamination, resulting in good thermal stability and high insulation safety. At the same time, it ensures sufficient foaming space for the foaming layer 233, which helps maintain the advantages of low dielectric and lightweight design.

[0067] As an example, the inner skin layer covers the two conductors. Specifically, the inner skin layer includes a first inner skin layer 231 and a second inner skin layer 232. The first inner skin layer 231 covers the first conductor 210, and the second inner skin layer 232 covers the second conductor 220. The two conductors are located inside the foamed insulation layer 230 and are insulated by the first inner skin layer 231, the second inner skin layer 232, and the foamed layer 233. The first inner skin layer 231 and the second inner skin layer 232 are automatically formed by the condensation of foamed material on the surface of the conductors. The mechanism is that after the molten plastic is extruded from the die, the inner layer of the foamed material quickly comes into contact with the cold conductor, the temperature drops rapidly, and the surface resin quickly solidifies to form a dense layer, similar to a skin layer, hence the name inner skin layer. Furthermore, the lower the conductor temperature, the thicker this dense layer; while the other parts of the foamed material maintain a higher temperature to maintain the microporous structure of the foamed insulation layer 230. This structural design uses a condensation method to generate the inner skin layer, saving the extruder head and solving the problem of poor adhesion between the conductor and the foamed insulation layer 230 in conventional foaming lines. In practical applications, the thickness of the inner skin layer can be controlled by adjusting the conductor pre-cooling temperature, which in turn helps to control the adhesion between the conductor and the rubber compound.

[0068] In various embodiments, the outer skin layer 240 covers the foamed insulation layer 230. As an example, the outer skin layer 240 covers the foamed insulation layer 230, and the material of the outer skin layer 240 includes, but is not limited to, PE, PP, PS, PET, PPO, PTFE, FEP, PFA, etc. The selection of the material of the outer skin layer 240 should be based on the principle that its melting temperature and melt index are close to those of the material of the foamed insulation layer 230. To ensure sufficient strength and moisture protection for the foamed insulation layer 230, in some embodiments, the thickness of the outer skin layer is not less than 0.01 mm. As an example, the thickness of the outer skin layer is greater than 0.01 mm; or, the thickness of the outer skin layer is greater than 0.05 mm; or, the thickness of the outer skin layer is greater than 0.1 mm. In order to reduce the number of processes, improve mechanical strength and enhance the moisture-proof function of the foamed insulation layer 230, in some embodiments, the outer skin layer 240 and the foamed insulation layer 230 are co-extruded together in one step and cover the first conductor 210 and the second conductor 220. That is, an additional outer skin layer 240 is added and formed together with the foamed insulation layer 230 in one step. Compared with two molding steps, the mechanical strength of the entire line is further improved without adding any additional processes, while preventing moisture from invading the foamed insulation layer 230.

[0069] This structural design serves several purposes. First, the first inner skin layer 231 and the second inner skin layer 232 respectively encapsulate the first conductor 210 and the second conductor 220, placing the two conductors entirely within the foamed insulation layer 230. Reliable insulation is achieved through the inner skin layer and the foamed layer 233, effectively preventing leakage and signal interference between conductors and ensuring the stability of differential transmission. Second, the inner skin layer is automatically formed by the condensation of foamed material. The molten foamed material rapidly solidifies into a dense layer upon contact with the cold conductor, eliminating the need for an additional extruder head, simplifying equipment configuration, and reducing production costs. It also addresses the issue of poor adhesion between the conductor and the foamed insulation layer 230 in conventional foamed wires, preventing interface peeling. Furthermore, the inner skin layer can be precisely controlled by adjusting the conductor pre-cooling temperature. The thickness of the inner skin layer is adjusted as the conductor temperature decreases, allowing for flexible control of the adhesion between the conductor and the adhesive to meet different application requirements. On the other hand, the outer skin layer 240 covers the foamed insulation layer 230, using a material with similar melting parameters to ensure tight interlayer bonding. Its thickness is limited to at least 0.1 mm, providing sufficient mechanical strength and moisture protection to prevent moisture from penetrating the foamed insulation layer 230 and maintain the stability of the microporous structure. Furthermore, the outer skin layer 240 and the foamed insulation layer 230 are co-extruded in a single process, eliminating the need for additional steps. Compared to two-stage molding, this significantly improves the overall mechanical strength and bending resistance of the production line, simplifying the production process and increasing efficiency, thus balancing structural reliability, moisture resistance, and manufacturing economy.

[0070] To prevent the cable from concave under bending or twisting conditions, which could cause defects, in some embodiments, such as Figure 8 As shown, in the cross-section, the foamed insulating layer 230 and the outer skin layer 240 together form an outward protrusion 290, and the outward protrusion 290 itself is axially symmetrical with respect to the axis of symmetry 280. Figure 8 In the illustrated embodiment, the data transmission line 200 has two protruding portions 290 on the cross-section. In this embodiment, the foamed insulation layer 230 and the outer sheath layer 240 have two protruding portions 290, forming an egg-like shape, i.e., with certain protrusions at both the top and bottom, to ensure the bending resistance of the wire in the thickness direction.

[0071] This structural design, on the one hand, allows the foamed insulation layer 230 and the outer sheath layer 240 to jointly form an outward protrusion 290, which is symmetrically arranged relative to the axis of symmetry 280. This ensures that the cross-section of the data transmission line 200 is subjected to uniform stress, effectively preventing concave deformation when the cable is bent or twisted, and preventing structural collapse and poor performance. On the other hand, the overall formation of two outward protrusions 290, in an oval shape, symmetrically protruding from top to bottom, can significantly improve the bending resistance in the thickness direction of the wire, disperse bending stress, reduce stress concentration, and reduce the risk of cracking and breakage. Furthermore, the axially symmetrical outward protrusion structure ensures the symmetry of the differential line pair on both sides, maintains stable electrical performance, and avoids impedance imbalance and signal crosstalk caused by asymmetrical deformation. It has advantages in terms of structural stability, bending resistance, and transmission reliability.

[0072] In each embodiment, such as Figure 3 As shown, in a cross-section along the length direction 260 of the data transmission line 200, the data transmission line 200 has an axis of symmetry 280. The first conductor 210 and the second conductor 220 are symmetrically arranged with respect to the axis of symmetry 280. The foamed insulating layer 230 and the outer sheath layer 240 are also symmetrically arranged with respect to the axis of symmetry 280. It can be understood that the data transmission line 200 essentially has a plane of symmetry, which, in a cross-section along the length direction 260 of the data transmission line 200, is represented by the axis of symmetry 280.

[0073] This structural design serves several purposes. First, it ensures that the first conductor 210 and the second conductor 220 are symmetrically arranged relative to the axis of symmetry 280, guaranteeing symmetrical positions and uniform spacing between the two conductors. This fundamentally ensures the symmetry of the differential line pair, reducing signal transmission loss and crosstalk. Second, the foamed insulation layer 230 and the outer sheath layer 240 are also symmetrically arranged relative to the axis of symmetry 280, resulting in uniform insulation layer thickness and outer sheath coverage. This ensures balanced stress on the entire line structure, improving bending resistance and mechanical stability. Third, the fully symmetrical structural design avoids electrical performance imbalances caused by differences in the structure on one side, ensuring stable differential impedance and improving the quality of high-frequency signal transmission. Fourth, it simplifies molding control, reduces process errors, and improves production consistency and product yield.

[0074] To enhance signal shielding and prevent interference, in some embodiments, such as Figure 4 As shown, the data transmission line 200 further includes a shielding layer 250, which covers the outer sheath 240. In some embodiments, such as Figure 5 As shown, along the direction 204 of the line connecting the centers of the first conductor 210 and the second conductor 220, the first conductor 210 and the second conductor 220 have a first distance 201, and either the first conductor 210 or the second conductor 220 has a second distance 202 with the shielding layer 250. That is, the first conductor 210 has a second distance 202 with the shielding layer 250, or the second conductor 220 has a second distance 202 with the shielding layer 250. Due to the symmetry with respect to the axis of symmetry 280, these two second distances 202 are the same; on the axis of symmetry 280... In the direction, either the first conductor 210 or the second conductor 220 has a third distance 203 from the shielding layer 250. Similarly, the first conductor 210 has a third distance 203 from the shielding layer 250, or the second conductor 220 has a third distance 203 from the shielding layer 250. Due to the symmetry with respect to the axis of symmetry 280, these two third distances 203 are the same. The first distance 201 is not greater than the second distance 202; or, the first distance 201 is not greater than the third distance 203; or, the second distance 202 is equal to the third distance 203. As an example, the first distance 201 is not greater than the second distance 202 and the second distance 202 is equal to the third distance 203.

[0075] This structural design, on the one hand, adds a shielding layer 250 covering the outer skin layer 240, which can effectively block external electromagnetic interference and signal leakage, significantly improve the anti-interference capability of the data transmission line 200, ensure stable high-frequency signal transmission, and reduce the impact of the external electromagnetic environment on differential signals; on the other hand, based on the symmetrical layout of the axis of symmetry 280, the second distance 202 and the third distance 203 from the first conductor 210 and the second conductor 220 to the shielding layer 250 are equal, ensuring that the spatial position between the two conductors and the shielding layer 250 is symmetrical and the electrical coupling is consistent. Structurally, this ensures impedance balance of the differential line pairs and avoids signal leakage caused by distance differences. The design addresses issues such as signal skew and increased crosstalk. Furthermore, by limiting the first distance 201 to no greater than the second distance 202 or the third distance 203, or even making the second distance 202 equal to the third distance 203, the coupling strength between conductors and the isolation between conductors and the shielding layer can be reasonably controlled, balancing differential transmission efficiency and shielding effect, thus optimizing signal integrity. Additionally, the symmetrical distance parameter design is compatible with the one-time co-extrusion molding process, facilitating dimensional accuracy control, reducing processing difficulty, and improving product consistency and yield. Simultaneously, it ensures that the shielding layer 250 is subjected to uniform force and tightly adhered, effectively enhancing the overall mechanical stability and shielding reliability of the production line.

[0076] To improve signal transmission performance, for example, such as Figure 6 As shown, the data transmission line 200 also includes a first ground wire 261 and a second ground wire 262 arranged symmetrically with respect to the axis of symmetry 280. The first ground wire 261 and the second ground wire 262 are located inside the shielding layer 250 and in contact with the shielding layer 250. They are co-extruded with the foamed insulating layer 230. That is, the two conductors including the first conductor 210 and the second conductor 220 and the two ground wires including the first ground wire 261 and the second ground wire 262 are co-extruded with the foamed insulating layer 230 in one step to form a whole, and then the shielding layer 250 is wrapped on the outside. Figure 6 In the embodiment shown, the ground wire is partially embedded in the foamed insulation layer 230, that is, the molding method of co-extruding two ground wires and two conductors with the foamed insulation layer 230 is adopted. The ground wires include a first ground wire 261 and a second ground wire 262.

[0077] This structural design, on the one hand, adds a first ground wire 261 and a second ground wire 262, which are symmetrically arranged relative to the axis of symmetry 280. This effectively discharges interference charges, optimizes the return path, and significantly improves the anti-interference capability and signal transmission effect of the data transmission line 200. On the other hand, the first ground wire 261 and the second ground wire 262 contact the shielding layer 250, so that the ground wire and the shielding layer 250 form a reliable electrical connection, enhancing the shielding effectiveness and reducing external electromagnetic interference and internal signal leakage. Furthermore, the two conductors, the two ground wires, and the foamed insulation layer 230 are co-extruded into a whole in one step, with the ground wire semi-embedded in the foamed insulation layer 230. The structure is stable and the position is precise, avoiding later displacement, greatly simplifying the production process and improving production efficiency. Moreover, this integral co-extruded structure ensures structural symmetry and electrical consistency as much as possible, effectively reducing impedance fluctuations and signal crosstalk, while taking into account transmission performance, shielding effect, and manufacturing processability.

[0078] In various embodiments, the data transmission line 200 may be a complete differential signal transmission line, or it may be part of a differential signal transmission line. To improve signal transmission performance, in some embodiments, such as... Figure 7 As shown, the data transmission line 200 further includes a first ground wire 261, a second ground wire 262, and a protective layer 270; the first ground wire 261 and the second ground wire 262 are symmetrically arranged with respect to the axis of symmetry 280 and are located outside the shielding layer 250; the protective layer 270 covers the shielding layer 250, the first ground wire 261, and the second ground wire 262, and the protective layer 270 itself is symmetrically arranged with respect to the axis of symmetry 280. Figure 7 In the illustrated embodiment, that is, in Figure 5 Based on the embodiment shown, a first ground wire 261, a second ground wire 262, and a protective layer 270 are added. The protective layer 270 can also be called an outer sheath or other names, so that it can serve as a complete differential signal transmission line.

[0079] This structural design offers several advantages. First, it allows the data transmission line 200 to function as a complete differential signal transmission line or a component thereof, providing flexibility and adaptability to various transmission scenarios and assembly requirements. Second, the addition of a first ground wire 261 and a second ground wire 262, symmetrically positioned relative to the axis of symmetry 280 and arranged outside the shielding layer 250, optimizes the signal return path, further suppresses electromagnetic interference and signal crosstalk, and improves the quality and stability of high-frequency signal transmission. Third, the addition of a protective layer 270 covering the shielding layer 250, the first ground wire 261, and the second ground wire 262, with its own symmetrical arrangement, provides reliable mechanical protection and moisture and weather resistance, protecting the internal structure from external damage and environmental corrosion, and extending its service life. Fourth, the overall symmetrical structure ensures symmetrical and stable electrical performance, and the one-piece molding improves production efficiency, enabling the data transmission line 200 to possess complete differential transmission functionality, thereby meeting the requirements for finished cable applications.

[0080] In some embodiments, a dual-nozzle extrusion die 300, such as... Figure 9 As shown, it is configured to prepare the data transmission line 200 described in any embodiment; the dual-nozzle extrusion die 300 includes an inner die 310 and an outer die 320 arranged coaxially, and the inner die 310 is provided with a foam material injection port 330 and an outer skin material injection port 340. This structural design, on the one hand, facilitates the one-time co-extrusion molding and production of the data transmission line 200 with a foam insulation layer 230 and an outer skin layer 240, that is, the foam insulation layer 230 and the outer skin layer 240 are sequentially wrapped around the two conductors through the dual-nozzle extrusion die 300, which can be completed in one process; on the other hand, it is understood that, since it is suitable for preparing the data transmission line 200 described in any embodiment, the dual-nozzle extrusion die 300 also has beneficial technical effects that match the data transmission line 200, which will not be elaborated here.

[0081] Combination Figure 10The first conductor 210 and the second conductor 220 of the data transmission line 200 pass through the inner mold 310 and the outer mold 320. The material of the foamed insulation layer 230 is injected into the inner mold 310 through the foamed material injection port 330, and the material of the outer skin layer 240 is injected into the inner mold 310 through the outer skin material injection port 340. As an example, the dual-injection-port extrusion mold 300 has a partition plate between the inner mold 310 and the outer mold 320. The material of the outer skin layer 240 is injected into the partition plate through the outer skin material injection port 340, and then covers the foamed insulation layer 230 of the semi-finished data transmission line 200 after passing through the partition plate. As an example, a partition plate is added between the inner mold 310 and the outer mold 320. The material of the outer skin layer 240 is first injected into the partition plate through the outer skin material injection port 340. The material of the outer skin layer 240 first flows through the partition plate and then onto the semi-finished product of the foamed material covering the foamed insulation layer 230 to form the outer skin layer 240.

[0082] This structural design, on the one hand, utilizes a coaxially arranged inner mold 310 and outer mold 320 in the dual-nozzle extrusion die 300, and is equipped with a foam material injection nozzle 330 and an outer skin material injection nozzle 340. Through a single co-extrusion process, the foamed insulation layer 230 and the outer skin layer 240 can sequentially cover the first conductor 210 and the second conductor 220, significantly simplifying the production process, shortening the molding cycle, avoiding positioning deviations and poor interlayer bonding caused by step-by-step processing, and greatly improving production efficiency and product consistency. On the other hand, the dual-nozzle extrusion die 300 is compatible with the data transmission line 200 described in any embodiment, offering strong versatility and reducing the number of dual-nozzle extrusion dies 300 required for multi-specification production. This reduces equipment investment and mold change and debugging costs, facilitating large-scale flexible production. Furthermore, an isolation plate is added between the inner mold 310 and the outer mold 320, allowing the outer skin layer 240 material to be injected into the isolation plate through the outer skin material injection port 340 before evenly covering the semi-finished foamed insulation layer 230. This effectively isolates the two molten materials, preventing the foaming material and the outer skin material from mixing or flowing together. This ensures the integrity of the microporous structure of the foamed insulation layer 230 and the uniformity of the outer skin layer 240 thickness, improving the overall line's structural symmetry, mechanical strength, and appearance quality. Additionally, the simple mold structure and precise positioning effectively ensure the stability of the spacing and coaxiality between the two conductors, thus guaranteeing the electrical performance of the differential line pair is symmetrical and reliable from the source.

[0083] It should be noted that other embodiments of this application also include a data transmission line and a dual-nozzle extrusion mold formed by combining the technical features of the above embodiments.

[0084] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0085] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. Therefore, the patent protection scope of this application should be determined by the appended claims.

Claims

1. A data transmission line (200), characterized by, It includes a first conductor (210), a second conductor (220), a foamed insulating layer (230), and an outer skin layer (240); The foamed insulating layer (230) is formed by one co-extrusion and covers the first conductor (210) and the second conductor (220), and the first conductor (210) and the second conductor (220) are separated by the foamed insulating layer (230); The outer skin layer (240) covers the foamed insulating layer (230); In a cross-section along the length direction (260) of the data transmission line (200), the data transmission line (200) has an axis of symmetry (280), the first conductor (210) and the second conductor (220) are symmetrically arranged with respect to the axis of symmetry (280), the foamed insulating layer (230) itself is symmetrically arranged with respect to the axis of symmetry (280), and the outer skin layer (240) itself is symmetrically arranged with respect to the axis of symmetry (280).

2. The data transmission line (200) according to claim 1, characterized in that The foamed insulation layer (230) includes a first inner skin layer (231), a second inner skin layer (232), and a foamed layer (233) formed by one co-extrusion. The first inner skin layer (231) covers the first conductor (210), the second inner skin layer (232) covers the second conductor (220), the foam layer (233) covers the first inner skin layer (231) and the second inner skin layer (232), and the first inner skin layer (231) and the second inner skin layer (232) are separated by the foam layer (233).

3. The data transmission line (200) according to claim 2, characterized in that The first endothelial layer (231) and the second endothelial layer (232) have the same thickness and are no greater than 1 mm.

4. The data transmission line (200) according to claim 1, characterized in that The foamed insulation layer (230) has a semi-closed or fully closed microporous structure formed by air-filling foaming, and the microporous structure is filled with a preset gas.

5. The data transmission line (200) according to claim 1, characterized in that The degree of foaming of the foamed insulation layer (230) is not less than 20%; or, The thickness of the outer skin layer is not less than 0.01 mm.

6. The data transmission line (200) according to claim 1, characterized in that In the cross-section, the foamed insulating layer (230) and the outer skin layer (240) together form an outward protrusion (290), and the outward protrusion (290) itself is axially symmetrical with respect to the axis of symmetry (280); or, The outer skin layer (240) and the foamed insulation layer (230) are co-extruded together and cover the first conductor (210) and the second conductor (220).

7. The data transmission line (200) according to any one of claims 1 to 6, characterized in that, The data transmission line (200) further includes a shielding layer (250) which covers the outer skin layer (240).

8. The data transmission line (200) according to claim 7, characterized in that In the direction (204) of the center line connecting the first conductor (210) and the second conductor (220), the first conductor (210) and the second conductor (220) have a first distance (201), and either the first conductor (210) or the second conductor (220) has a second distance (202) from the shielding layer (250). In the direction of the axis of symmetry (280), either the first conductor (210) or the second conductor (220) has a third distance (203) from the shielding layer (250). The first distance (201) is not greater than the second distance (202); or, The first distance (201) is not greater than the third distance (203); or, The second distance (202) is equal to the third distance (203).

9. The data transmission line (200) according to claim 7, characterized in that The data transmission line (200) also includes a first ground wire (261), a second ground wire (262), and a protective layer (270). The first ground wire (261) and the second ground wire (262) are arranged symmetrically with respect to the axis of symmetry (280) and are located outside the shielding layer (250); The protective layer (270) covers the shielding layer (250), the first ground wire (261) and the second ground wire (262), and the protective layer (270) itself is symmetrical about the axis of symmetry (280).

10. A dual injection gate extrusion die (300) characterized by, Configured to prepare a data transmission line (200) as described in any one of claims 1 to 9; The dual-injection-gate extrusion mold (300) includes an inner mold (310) and an outer mold (320) arranged coaxially, and the inner mold (310) is provided with a foam material injection port (330) and an outer skin material injection port (340).

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