Skeleton airway air blowing micro-cable and preparation method thereof

Abstract

The application discloses a skeleton airway air blowing micro cable and a preparation method thereof, and belongs to the technical field of optical cable preparation, which comprises: a traction optical unit; an extrusion die is arranged, and a first flow channel and a second flow channel are arranged in the extrusion die; an air blowing pipeline is arranged, and a material injection hole is formed in the air blowing pipeline in a radial direction; the optical unit twisted into a bundle is introduced into the first flow channel, the air blowing pipeline is introduced into the second flow channel, and airflow is blown into the air blowing pipeline; an outer sheath is extruded and formed, the sheath material enters the air blowing pipeline from the material injection hole, and the sheath material forms a skeleton protrusion in the air blowing pipeline and is cooled and shaped. The preparation method of the skeleton airway air blowing micro cable in the application has a simple forming mode, on the basis of embedding the air blowing pipeline in the extrusion die, the forming of the skeleton protrusion in the air blowing hole can be realized only by simply forming the material injection hole, the skeleton protrusion can increase the friction with airflow during laying, and the laying distance of the air blowing micro cable is greatly increased.

Description

Technical Field

[0001] This invention belongs to the field of optical cable manufacturing technology, specifically relating to a skeleton air-blown microcable and its manufacturing method. Background Technology

[0002] With the arrival of the 5G era, data is growing explosively, and massive amounts of data need to be processed through dense networking.

[0003] Air-blown microcables are optical cables that can be installed using air-blowing methods. They offer advantages such as high fiber density, small diameter, light weight, and high air-blowing installation efficiency, making them widely used in backbone networks, local area networks, and access networks, effectively saving pipeline resources. While air-blown microcables boast high installation efficiency, their small size and flexible structure mean they can easily accumulate at the bottom of the pipeline during installation. This results in only a small amount of airflow providing propulsion, wasting significant air-blowing energy. Furthermore, the surface of the microcable can easily rub against the inner wall of the pipeline, hindering the air-blowing process. Additionally, once the pipeline is installed using air-blowing technology, pipeline resources are occupied, preventing secondary expansion and hindering subsequent network upgrades. Summary of the Invention

[0004] In view of one or more of the above-mentioned defects or improvement needs of the prior art, the present invention provides a skeleton air channel air-blown microcable and its preparation method, so as to solve the problem that the existing air-blown microcable wastes a lot of air-blowing kinetic energy during the air-blowing process, resulting in a short air-blowing distance.

[0005] To achieve the above objectives, the present invention provides a method for preparing a skeleton airway air-blown microcable, which includes the following steps: S1, Traction Light Unit; S2. Set up an extrusion die, and arrange the first flow channel and the second flow channel in the extrusion die respectively; S3. Install an air blowing pipe and open injection holes radially along the air blowing pipe; S4. A stranded optical unit is introduced into the first flow channel, and an air blowing pipe is introduced into the second flow channel, and airflow is blown into the air blowing pipe. S5. Extrusion molding of the outer sheath: The sheath material enters the air blowing pipe from the injection hole, and the sheath material forms a skeleton protrusion in the air blowing pipe, which is then cooled and shaped.

[0006] As a further improvement of the present invention, step S3 specifically includes: Pull the air blowing pipe, drill holes radially along the air blowing pipe, form injection holes on the circumferential surface of the air blowing pipe, and grind the injection holes.

[0007] As a further improvement of the present invention, in step S3, the injection hole is drilled using a conical drilling device so that a conical injection hole with a wider outer side and a narrower inner side is formed on the surface of the air blowing pipe.

[0008] As a further improvement of the present invention, the air blowing pipe in step S3 is made of PBE, PC or PET.

[0009] As a further improvement of the present invention, step S3 specifically includes: covering the surface of the air blowing pipe with a PE film, drilling holes along the radial direction of the air blowing pipe, and attaching the PE film to the circumferential inner wall of the injection hole with the drilling equipment.

[0010] As a further improvement of the present invention, step S4 further includes: A closed cavity is set at the front end of the extrusion die. The closed cavity is fitted around the outer periphery of the air blowing pipe. Molding material is injected into the closed cavity. The molding material enters the air blowing pipe through the injection hole and moves along the extension direction of the air blowing pipe with the airflow.

[0011] As a further improvement of the present invention, the diameter of the injection hole in this application is 0.1~1mm.

[0012] This application also includes a skeletal airway air-blowing microcable, which comprises: At least one optical unit is provided with an outer sheath disposed on the outer periphery of the optical unit. The outer sheath has a plurality of air blowing holes along the axial direction. The plurality of air blowing holes have skeleton protrusions formed along the radial direction of the holes. The skeleton protrusions are randomly arranged along the axial direction of the air blowing holes and block the radial portion of the holes.

[0013] As a further improvement of the present invention, the air blowing hole is formed by an air blowing pipe disposed in the outer sheath, and a plurality of injection holes are formed on the air blowing pipe arranged along the axial direction. The sheath material of the outer sheath passes through the injection holes and extends into the air blowing pipe to form the skeleton protrusion.

[0014] As a further improvement of the present invention, the outer sheath surface has a plurality of radially protruding air-blowing ridges, and the plurality of air-blowing ridges are arranged spirally wound along the axial direction of the outer sheath.

[0015] The aforementioned improved technical features can be combined with each other as long as they do not conflict with each other.

[0016] In summary, the beneficial effects of the above-described technical solutions conceived by this invention compared with the prior art include: (1) The skeleton air channel air blowing micro cable of the present invention forms an air blowing hole in the sheath layer of the air blowing micro cable and forms a skeleton protrusion in the air blowing hole. During the air blowing process, the air blowing hole itself can be filled with airflow. The air blowing micro cable is pushed forward by the friction between the airflow and the inner wall of the air blowing hole, so as to increase the air blowing distance of the air blowing micro cable. At the same time, the skeleton protrusion inside the air blowing hole will also obstruct the flow of airflow, thereby increasing the pushing distance of the airflow on the air blowing micro cable and greatly increasing the laying distance of the air blowing micro cable.

[0017] (2) The method for preparing the skeleton air-blown microcable of the present invention involves embedding an air-blown pipe in an extrusion mold and opening a material injection hole on the air-blown pipe. When the outer sheath is extruded and formed on the outer periphery of the optical unit, part of the sheath material enters the inner cavity of the air-blown pipe through the material injection hole and forms a protruding structure inside the air-blown pipe. Then, the protruding structure is accelerated and cooled by airflow. Finally, the outer sheath is cooled and formed as a whole to form a skeleton protrusion inside the air-blown pipe. The method for preparing the skeleton air-blown microcable of the present application has a simple forming method. Based on embedding the air-blown pipe in the extrusion mold, the skeleton protrusion inside the air-blown hole can be formed simply by opening a material injection hole. The skeleton protrusion can increase the friction with the airflow during laying, which can greatly increase the laying distance of the air-blown microcable.

[0018] (3) The method for preparing the skeleton air channel air-blown micro cable of the present invention, by coating the surface of the air-blown pipe with a PE film and setting the injection hole to a conical shape, can ensure that the sheath material flows stably from the outside of the air-blown pipe into the inside of the air-blown pipe to form a skeleton protrusion inside the air-blown pipe, and can also limit the amount of material entering the inside of the air-blown pipe, avoiding problems such as blockage of the air-blown pipe caused by excessive sheath material inside the air-blown pipe, thus greatly improving the forming rate of the skeleton air channel air-blown micro cable and ensuring product yield.

[0019] (4) The method for preparing the skeleton air channel air-blown micro cable of the present invention involves setting a sealed cavity at the front end of the extrusion die and introducing molding material into the injection hole through the sealed cavity. The molding material can adhere to the inner wall of the injection hole and the inside of the air-blown pipe. When the sheath material flows into the air-blown pipe through the injection hole, the molding material can accelerate the shaping of the sheath material to form skeleton protrusions in the air-blown pipe, avoiding excessive sheath material flowing into the air-blown pipe and causing the air-blown pipe to be blocked, thus ensuring the molding of the skeleton air channel air-blown micro cable and effectively improving the product yield. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of the skeleton airway air-blowing microcable in an embodiment of the present invention; Figure 2 This is an extrusion schematic diagram of the preparation method of the skeleton airway air-blown microcable in an embodiment of the present invention.

[0021] In all the accompanying drawings, the same reference numerals denote the same technical features, specifically: 1. Optical unit; 2. Outer sheath; 3. Air blow hole; 4. Frame protrusion; 5. Air blow ridge; 6. Water barrier strip; 7. Extrusion die; 8. Air blow pipe. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0023] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0024] 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 invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0025] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0026] In this invention, unless otherwise explicitly 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 is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply 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 that the first feature is at a lower horizontal level than the second feature.

[0027] Example: Please see Figure 1 , Figure 2 In a preferred embodiment of the present invention, the skeleton air channel air blowing microcable includes at least one optical unit 1. The optical unit 1 is provided with an outer sheath 2 on its outer periphery. The outer sheath 2 is provided with a plurality of air blowing holes 3 along the axial direction. The plurality of air blowing holes 3 are provided with skeleton protrusions 4 along the radial direction of the channel. The skeleton protrusions 4 are arranged along the axial direction of the air blowing holes 3 and block the radial portion of the channel of the air blowing holes 3.

[0028] The air-blowing microcable with a skeleton air duct in this invention has air-blowing holes 3 formed inside the sheath layer of the air-blowing microcable, and a radially extending skeleton protrusion 4 formed within the air-blowing holes 3. During the laying of the air-blowing microcable, the air-blowing holes 3 themselves can be used to introduce airflow, and the friction between the airflow and the inner wall of the air-blowing holes 3 is used to propel the air-blowing microcable forward, thereby increasing the air-blowing distance of the air-blowing microcable; at the same time, the skeleton protrusion 4 inside the air-blowing holes 3 also obstructs the flow of airflow, increasing the friction between the airflow and the skeleton air duct air-blowing microcable, thereby further increasing the propulsion distance of the air-blowing microcable.

[0029] Optionally, the outer sheath 2 of this application is provided with a plurality of optical units 1, which can be arranged in a reinforced twisted arrangement or loosely placed inside the outer sheath 2.

[0030] Preferably, the outer sheath 2 in this application can be made of one of PE (polyethylene), PP (polypropylene), PVC (polyvinyl chloride) or LSZH (low smoke halogen-free material).

[0031] As a further preferred embodiment of the present invention, multiple reinforcing cores are embedded axially inside the outer sheath 2. These reinforcing cores can be one or more of steel wire, GFRP (glass fiber reinforced material), KFRP (aramid fiber reinforced material), or aramid fiber. Furthermore, the outer periphery of the optical unit 1 is also covered with a water-blocking tape 6, water-blocking yarn, or coated with water-blocking paste to ensure the water-blocking capability of the air-blown microcable.

[0032] Furthermore, in this application, the air-blowing hole 3 is formed by an air-blowing pipe 8 disposed within the outer sheath 2. Simultaneously, multiple injection holes are formed on the air-blowing pipe 8 arranged axially. The sheathing material of the outer sheath 2 extends into the air-blowing pipe 8 through the injection holes and forms the aforementioned skeleton protrusion 4. As an optional embodiment of this application, this application mainly embeds the air-blowing pipe 8 within the outer sheath 2 and opens injection holes on the air-blowing pipe 8. The skeleton protrusion 4 is formed by extruding the sheathing material into the air-blowing pipe 8. This forming method has a simple structure and does not significantly increase the difficulty of the air-blown micro-cable manufacturing process, achieving rapid forming of the skeleton protrusion 4 within the air-blowing pipe 8.

[0033] Furthermore, as a preferred embodiment of the present invention, the outer sheath 2 of this application has a plurality of radially protruding air-blowing ridges 5, which are spirally wound along the axial direction of the outer sheath 2. To increase the air-blowing distance of the air-blowing microcable, in addition to changing the friction between the airflow and the air-blowing hole 3, the friction between the airflow and the surface of the outer sheath 2 can also be increased. Based on this, the present application arranges spirally wound air-blowing ridges 5 on the surface of the outer sheath 2. When the air-blowing ridges 5 abut against the pipe wall, a gap is formed between the air-blowing ridges 5 and the pipe, reducing the contact area between the air-blowing microcable and the pipe, thereby reducing the friction between the air-blowing microcable and the pipe and increasing the air-blowing distance of the air-blowing microcable. Specifically, the air-blowing ridge 5 structure on the surface of the outer sheath 2 can be achieved by changing the shape of the extrusion die 7; simply changing the extrusion shape of the extrusion die 7 to have a protruding structure is sufficient. Meanwhile, after the outer sheath 2 is cooled and formed, the outer sheath 2 is driven to rotate or swing radially by the rotating structure. The formed outer sheath 2 rotates with the rotating structure, and the outer sheath 2 that has just been extruded from the extrusion die 7 swings accordingly, thereby forming air blown ridges 5 arranged in a spiral on the surface of the outer sheath 2.

[0034] Furthermore, this application also includes a method for preparing a skeleton airway air-blown microcable, which is used to prepare the above-mentioned skeleton airway air-blown microcable, and includes the following steps: S1, Traction Light Unit 1; S2. Set up an extrusion die 7, and arrange the first flow channel and the second flow channel in the extrusion die 7 respectively; S3. Install air blowing pipe 8 and open injection holes radially along air blowing pipe 8; S4. A stranded optical unit 1 is introduced into the first flow channel, and an air blowing pipe 8 is introduced into the second flow channel, and airflow is blown into the air blowing pipe 8. S5. Extrusion molding of outer sheath 2. Sheath material enters air blowing pipe 8 from injection hole. Sheath material forms skeleton protrusion 4 in air blowing pipe 8 and cools and solidifies.

[0035] The method for preparing the skeleton air-blown microcable in this application involves embedding an air-blown pipe 8 within an extrusion die 7 and creating injection holes in the air-blown pipe 8. During the extrusion molding of the outer sheath 2 around the optical unit 1, some sheath material enters the inner cavity of the air-blown pipe 8 through the injection holes, forming a protruding structure within the air-blown pipe 8. The protruding structure is then rapidly cooled by airflow, and finally, the outer sheath 2 is cooled and molded as a whole, forming a skeleton protrusion 4 within the air-blown pipe 8. The skeleton protrusion 4 obstructs airflow during the laying of the skeleton air-blown microcable, increasing the friction between the airflow and the skeleton air-blown microcable, thereby improving the laying distance of the skeleton air-blown microcable.

[0036] Furthermore, in step S1 of this application, the optical unit 1 can be formed by stranding a reinforcing core, or it can be directly placed into the outer sheath 2. Correspondingly, when the outer sheath 2 reserves space for the optical unit 1 to move, the outer sheath 2 needs to be formed by vacuum sizing.

[0037] Furthermore, as a preferred embodiment of the present invention, step S3 in this application specifically includes: The air-blowing pipe 8 is pulled, and holes are drilled radially along the air-blowing pipe 8 to form injection holes on the circumferential surface of the air-blowing pipe 8. The injection holes are then polished. When forming injection holes on the surface of the air-blowing pipe 8, drilling equipment is mainly used to drill holes on the surface of the air-blowing pipe 8. At the same time, the circumferential sidewalls of the injection holes are polished to improve the smoothness of the injection hole surface, so as to facilitate the sheath material to enter the interior of the air-blowing pipe 8 from the injection holes, thereby facilitating the formation of the skeleton protrusion 4.

[0038] Furthermore, as a preferred embodiment of the present invention, the injection holes on the surface of the air-blowing pipe 8 are drilled using a conical drilling device. The conical drilling device can form a conical injection hole with a wider outer diameter and a narrower inner diameter on the surface of the outer sheath 2. This application aims to increase the probability of sheath material entering the interior of the air-blowing pipe 8 to form the skeleton protrusion 4 within the air-blowing pipe 8; on the other hand, it needs to limit the amount of material entering the air-blowing pipe 8 to prevent excessive sheath material from causing blockage. Therefore, this application forms a conical injection hole on the surface of the air-blowing pipe 8. The structure of the wider outer diameter and narrower inner diameter allows the sheath material to smoothly enter the injection hole, and the narrow aperture connected to the inner wall of the air-blowing pipe 8 can limit the amount of material entering the air-blowing pipe 8, ensuring the formation of the skeleton air passage.

[0039] Furthermore, as a preferred embodiment of the present invention, the air-blowing pipe 8 in step S3 is made of materials with relatively high modulus such as PBT, PC, and PET. To retain sufficient air-blowing space and minimize the size of the air-blowing pipe 8, the thickness of the air-blowing pipe 8 is between 0.05 and 0.3 mm. Since the present application requires drilling holes in the outer wall of the air-blowing pipe 8, the air-blowing pipe 8 needs to have a certain degree of hardness to ensure the formation of the injection hole. At the same time, when the outer sheath 2 is extruded and formed in the extrusion mold 7, the sheath material will apply a certain pressure to the air-blowing pipe 8. Using materials with relatively high modulus such as PBT, PC, and PET can enable the air-blowing pipe 8 to have shape retention ability, thereby achieving stable formation of the air-blowing hole 3.

[0040] Furthermore, as an optional embodiment of the present invention, step S3 in this application specifically includes: A PE film is wrapped around the surface of the air blowing pipe 8, and holes are punched radially along the air blowing pipe 8. The PE film is then attached to the circumferential inner wall of the injection hole by the punching equipment.

[0041] When forming injection holes on the surface of the air-blowing pipe 8 using a drilling device, the drilling device will bring some PE film into the inner wall of the injection hole. PE itself has a friction coefficient of only 0.03~0.2, which can significantly increase the flow rate of the sheath material in the injection hole, facilitating the formation of the skeleton protrusions 4 inside the air-blowing pipe 8. In a conventional air-blowing pipe 8 structure, the sheath material tends to get stuck at the injection hole when injected, resulting in less sheath material entering the air-blowing pipe 8. This leads to smaller skeleton protrusions 4 formed inside the air-blowing pipe 8, making it impossible to form a stable skeleton protrusion 4 structure on the inner wall of the air-blowing pipe 8, thus affecting the air-blowing effect of the air-blowing micro-cable.

[0042] Furthermore, as a preferred embodiment of the present invention, step S4 in this application further includes: setting a closed cavity at the front end of the extrusion mold 7, fitting the closed cavity around the outer periphery of the air blowing pipe 8, injecting molding material into the closed cavity, the molding material entering the interior of the air blowing pipe 8 through the injection hole, and moving along the extension direction of the air blowing pipe 8 with the airflow. Since the air blowing pipe 8 in this application needs to be embedded in the outer sheath 2, the air blowing pipe 8 and the light unit 1 have the same extension structure. Conventional methods can only inject airflow in the second flow channel, and cannot inject airflow or molding material into the dynamic air blowing pipe 8. Based on this, this application sets a closed cavity with a three-way structure, where two ports are used for the air blowing pipe 8 to pass through, and the other port is used for the injection of airflow and molding material. The airflow and molding material enter the interior of the air blowing pipe 8 through the injection hole, and are transported to the extrusion mold 7 with the air blowing pipe 8, thereby accelerating the molding of the sheath material entering the air blowing pipe 8, so as to form a skeleton protrusion 4 inside the air blowing pipe 8. Meanwhile, the sheath material entering the air blowing pipe 8 does not need to form a circular tubular structure like the outer sheath 2. The skeleton protrusion 4 can be quickly formed by molding material to avoid the problem of the sheath material blocking the air blowing pipe 8.

[0043] Optionally, the main function of the molding material in this application is to achieve rapid curing of the sheathing material within the air-blowing pipe 8. As one optional embodiment, the molding material in this application is a powder with high specific heat capacity, such as sand powder, graphene, ceramics, etc. It does not react with the sheathing material and can cool the sheathing material, thereby achieving cooling and molding of the sheathing material within the air-blowing pipe 8.

[0044] Furthermore, as a preferred embodiment of the present invention, the diameter of the injection hole in this application is 0.1~1mm. Here, the diameter of the injection hole refers to the size of the hole on the inner wall of the air blowing pipe 8. By controlling the size of the injection hole, the amount of material entering the sheath inside the air blowing pipe 8 can be controlled, ensuring the formation of the skeleton protrusion 4 and avoiding blockage of the air blowing pipe 8.

[0045] Example 1: Six optical units (1) were fabricated using 250μm optical fibers. Water-blocking tape (6) was wrapped around the outer periphery of each unit. The outer sheath (2) was extruded to a thickness of 1.5mm. The height of the air-blowing ridge (5) was 0.2~0.4mm, and the cable diameter was 12mm. The air-blown microcable was then air-blown through a 20mm / 16mm pipe using a PLUMETT 600 air blower with a maximum air-blowing pressure of 8 bar. The maximum air-blowing distance of the microcable within the pipe was measured.

[0046] Example 2: Six optical units 1 were fabricated using 250μm optical fibers. Water-blocking tape 6 was wrapped around the outer periphery of each optical unit 1. The outer sheath 2 was extruded to a thickness of 1.5mm. The height of the air-blowing ridge 5 was 0.2~0.4mm, and the cable diameter was 12mm. Four 0.8mm / 0.6mm air-blowing channels 8, fabricated using PC, were embedded within the outer sheath 2. The air-blown microcable was then air-blown through these 20mm / 16mm channels using a PLUMETT 600 air-blowing machine with a maximum air-blowing pressure of 8 bar. The maximum air-blowing distance of the microcable within the channels was measured.

[0047] Example 3: Six optical units 1 were fabricated using 250μm optical fibers. Water-blocking tape 6 was wrapped around the outer periphery of each unit 1. The outer sheath 2 was extruded to a thickness of 1.5mm. The height of the air-blowing ridges 5 ranged from 0.2 to 0.4mm, and the cable diameter was 12mm. Four 0.8mm / 0.6mm air-blowing channels 8, fabricated using PC, were embedded within the outer sheath 2. Each air-blowing channel 8 had a spirally arranged injection hole on its outer periphery, spaced 10mm apart axially, with a hole diameter of 0.2mm. The air-blown microcable was then air-blown within the 20mm / 16mm channels using a PLUMETT 600 air-blowing machine at a maximum air-blowing pressure of 8 bar. The maximum air-blowing distance of the microcable within the channels was measured.

[0048] Example 4: Six optical units 1 were fabricated using 250μm optical fibers. Water-blocking tape 6 was wrapped around the outer periphery of each unit 1. The outer sheath 2 was extruded to a thickness of 1.5mm. The height of the air-blowing ridge 5 was 0.2~0.4mm, and the cable diameter was 12mm. Four 0.8mm / 0.6mm air-blowing channels 8, fabricated using PC, were embedded within the outer sheath 2. Each air-blowing channel 8 had a spirally arranged injection hole on its outer periphery, spaced 10mm apart axially. The injection holes had a tapered structure, wider at the outer edge and narrower at the inner edge, with an inner diameter of 0.2mm. The air-blown microcable was then air-blown within the 20mm / 16mm channels using a PLUMETT 600 air-blowing machine at a maximum air-blowing pressure of 8 bar. The maximum air-blowing distance of the microcable within the channels was measured.

[0049] Example 5: Six optical units 1 were fabricated using 250μm optical fibers. Water-blocking tape 6 was wrapped around the outer periphery of each unit 1. The outer sheath 2 was extruded to a thickness of 1.5mm. The height of the air-blowing ridge 5 was 0.2~0.4mm, and the cable diameter was 12mm. Four 0.8mm / 0.6mm air-blowing channels 8, fabricated using PC, were embedded within the outer sheath 2. The channels were covered with a 0.1mm thick PE film. Each channel 8 had a spirally arranged injection hole on its outer periphery, with the hole having a tapered structure that was wider at the outer edge and narrower at the inner edge. The axial spacing of the injection holes was 10mm, and the inner diameter of the injection hole was 0.2mm. The air-blown microcable was then air-blown within the 20mm / 16mm channels using a PLUMETT 600 air-blowing machine with a maximum air-blowing pressure of 8 bar. The maximum air-blowing distance of the microcable within the channels was measured.

[0050] Example 6: Six optical units 1 are fabricated using 250μm optical fibers. Water-blocking tape 6 is wrapped around the outer periphery of each unit 1. The outer sheath 2 is extruded to a thickness of 1.5mm. The height of the air-blowing ribs 5 is 0.2~0.4mm, and the cable diameter is 12mm. Four 0.8mm / 0.6mm air-blowing pipes 8, fabricated using PC, are embedded within the outer sheath 2. The air-blowing pipes 8 are covered with a 0.1mm thick PE film. Each air-blowing pipe 8 has a spirally arranged injection hole on its outer periphery, with the injection hole having a tapered structure that is wider at the outer edge and narrower at the inner edge. The axial spacing of the injection holes is 10mm, and the inner diameter of the injection hole is 0.2mm. A molding material, consisting of sand and gravel powder, is introduced into the injection hole. The air-blown microcable was air-blown in a 20mm / 16mm pipe using a PLUMETT600 air blower with a maximum air-blowing pressure of 8 bar. The maximum air-blowing distance of the microcable in the pipe was obtained.

[0051] The air blowing distances in the air blowing pipelines for Examples 1-6 described above are shown in the table below:

[0052] The above comparison shows that the method for preparing the skeleton air duct air-blown microcable in this application can effectively form the skeleton protrusion 4 structure inside the air-blown pipe 8. Furthermore, by treating the surface of the injection hole, adjusting the shape of the injection hole, covering the surface of the air-blown pipe 8 with a PE film, and injecting molding material, the forming length of the skeleton protrusion 4 inside the air-blown pipe 8 can be effectively increased. This increases the friction between the airflow and the skeleton air duct air-blown microcable without clogging the air-blown pipe 8, and significantly increases the laying distance of the skeleton air duct air-blown microcable.

[0053] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing a skeleton airway air-blown microcable, characterized in that, Includes the following steps: S1, Traction Light Unit; S2. Set up an extrusion die, and arrange the first flow channel and the second flow channel in the extrusion die respectively; S3. Install an air blowing pipe and open injection holes radially along the air blowing pipe; S4. A stranded optical unit is introduced into the first flow channel, and an air blowing pipe is introduced into the second flow channel, and airflow is blown into the air blowing pipe. S5. Extrusion molding of the outer sheath: The sheath material enters the air blowing pipe from the injection hole, and the sheath material forms a skeleton protrusion in the air blowing pipe, which is then cooled and shaped.

2. The method for preparing the skeleton airway air-blown microcable according to claim 1, characterized in that, Step S3 specifically includes: Pull the air blowing pipe, drill holes radially along the air blowing pipe, form injection holes on the circumferential surface of the air blowing pipe, and grind the injection holes.

3. The method for preparing the skeleton airway air-blown microcable according to claim 2, characterized in that, In step S3, the injection hole is drilled using a tapered drilling device to form a tapered injection hole that is wider on the outside and narrower on the inside of the air blowing pipe.

4. The method for preparing the skeleton airway air-blown microcable according to claim 1, characterized in that, In step S3, the air blowing pipe is made of PBE, PC or PET.

5. The method for preparing the skeleton airway air-blown microcable according to claim 1, characterized in that, Step S3 specifically includes: A PE film is wrapped around the surface of the air blowing pipe, and holes are punched along the radial direction of the air blowing pipe. The PE film is then attached to the inner wall of the injection hole by the punching equipment.

6. The method for preparing the skeleton airway air-blown microcable according to claim 1, characterized in that, Step S4 further includes: A closed cavity is set at the front end of the extrusion die. The closed cavity is fitted around the outer periphery of the air blowing pipe. Molding material is injected into the closed cavity. The molding material enters the air blowing pipe through the injection hole and moves along the extension direction of the air blowing pipe with the airflow.

7. The method for preparing the skeleton airway air-blown microcable according to claim 1, characterized in that, The diameter of the injection hole is 0.1~1mm.

8. A skeleton airway air-blown microcable, characterized in that, include: At least one optical unit, an outer sheath disposed on the outer periphery of the optical unit, the outer sheath having a plurality of air blowing holes along the axial direction, the plurality of air blowing holes having skeleton protrusions formed along the radial direction of the holes, the skeleton protrusions being arranged along the axial direction of the air blowing holes and blocking the radial portion of the holes. The air blowing hole is formed by an air blowing pipe disposed inside the outer sheath. The air blowing pipe has a plurality of injection holes arranged along the axial direction. The sheath material of the outer sheath passes through the injection holes and extends into the air blowing pipe to form the skeleton protrusion.

9. The skeleton airway air-blown microcable according to claim 8, characterized in that, The outer sheath surface has a plurality of radially protruding air-blowing ridges, which are spirally wound along the axial direction of the outer sheath.

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