Air-blown fiber optic cable

Abstract

An air-blown fiber optic cable, comprising a cable core (1) and an outer jacket (3) covering the cable core (1); a protrusion (5) is provided on an outer wall of the outer jacket (3); a height direction of the protrusion (5) extends toward an outer side along a radial direction of the fiber optic cable; a length direction of the protrusion (5) extends along an axial direction of the air-blown fiber optic cable and extends helically around an outer surface of the outer jacket (3); gas moves forward in a helical direction of the protrusion (5) and generates a thrust component on the fiber optic cable in the axial direction, wherein a driving force Ff generated by the thrust component to move each meter of the fiber optic cable is greater than 50 N. Providing a protrusion (5) on an outer side of an outer jacket (3) reduces frictional force between a fiber optic cable and an outer conduit during deployment, ensuring successful deployment of the air-blown fiber optic cable. In addition, controlling a driving force Ff for propelling the fiber optic cable by gas to be greater than 50 N per meter allows for fiber optic cable deployment to be completed more quickly and smoothly, thereby saving time and labor.

Description

A type of air-blown optical cable

[0001] This application claims priority to Chinese Patent Application No. 202510356529.5, filed on March 25, 2025, entitled “An Air-blown Optical Cable”, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to optical cable products, and more particularly to an air-blown optical cable. Background Technology

[0003] Air-blown fiber optic cable is a technology that uses compressed gas (usually air) to propel optical fibers or electrical cables through a conduit. This technology is primarily used for fiber optic or cable cabling, especially in locations where manual laying is difficult, such as long-distance underground ducts. Air-blown fiber optic cables offer advantages such as efficient cable laying, reduced damage, long-distance cable laying, reduced labor intensity, and high scalability, making them widely used in the telecommunications industry and other fields requiring long-distance cable laying, particularly in the construction of fiber optic networks.

[0004] However, the current air-blown optical cable has low laying efficiency and cannot complete the laying of optical cable quickly and efficiently. Therefore, there is a need for an optical cable that can complete the laying quickly and efficiently. Summary of the Invention

[0005] This application overcomes the shortcomings of the prior art and provides an air-blown optical cable.

[0006] To achieve the above objectives, the technical solution adopted in this application is as follows: an air-blown optical cable includes a cable core and an outer sheath covering the cable core. A protruding strip is provided on the outer wall of the outer sheath. The height direction of the protruding strip extends outward along the radial direction of the optical cable, and the length direction of the protruding strip extends along the length direction of the air-blown optical cable, spiraling around the outer surface of the outer sheath. Gas advances along the spiral direction of the protruding strip, generating a thrust component on the optical cable in the axial direction. The thrust component drives a pushing force F per meter of optical cable to move. f The driving force F is greater than 50N per meter. f The calculation formula is: F f =S·μ(θ)·P P ·h;

[0007] in: μ(θ) = μ·sinθ;

[0008] F f This refers to the pushing force exerted on the optical cable during the air blowing process;

[0009] S is the total length of the convex strip after it is unfolded along the circumference of the optical cable from the starting point of the convex strip.

[0010] μ(θ) is the compound friction multiplier;

[0011] r is the radius of the optical cable sheath;

[0012] p is the pitch;

[0013] L is the total length of the optical cable;

[0014] θ is the acute angle between the spiral protrusion and the axial direction of the optical cable;

[0015] P P Given the pressure inside the pipe of the air blowing device and pipeline;

[0016] h is the height of the raised strip.

[0017] More specifically, the pitch of the spiral ribs is set to be less than or equal to 0.5m.

[0018] More specifically, the pitch of the spiral ribs is set to 0.01-0.5m.

[0019] More specifically, on any radial surface of the air-blown optical cable, the shape of the protrusion is set to be arc-shaped or trapezoidal.

[0020] More specifically, a reinforcing member is provided inside the outer sheath, and the reinforcing member is evenly distributed circumferentially inside the outer sheath.

[0021] More specifically, the reinforcing member is configured as an aramid fiber rod or a glass fiber rod.

[0022] More specifically, the outer sheath is made of polyethylene material.

[0023] More specifically, the cable core includes a plurality of optical fibers and an adhesive portion that intermittently bonds the plurality of optical fibers in the axial direction. Two colored wires are provided outside the plurality of optical fibers, and the two colored wires are wrapped in opposite directions to bundle the plurality of optical fibers into a bundle.

[0024] More specifically, any adhesive portion on any optical fiber is a first reference adhesive portion, an adjacent adhesive portion on an optical fiber adjacent to the first reference adhesive portion is a second reference adhesive portion, and an adjacent adhesive portion on an optical fiber adjacent to the second reference adhesive portion is a third reference adhesive portion, and the first reference adhesive portion, the second reference adhesive portion, and the third reference adhesive portion are on the same straight line.

[0025] More specifically, the rigidity of the air-blown optical cable is set to 0.45-1.85 N·m. 2 .

[0026] This application addresses the deficiencies in the prior art and has the following beneficial effects: A raised strip is provided on the outer side of the outer sheath to reduce the friction between the optical cable and the outer duct during installation, ensuring the successful installation of the air-blown optical cable; simultaneously, the driving force F of the gas propelling the optical cable is controlled. f With a strength greater than 50N per meter, optical cables can be laid more quickly and smoothly, saving time and effort. Attached Figure Description

[0027] The present application will be further described below with reference to the accompanying drawings and embodiments.

[0028] Figure 1 is a cross-sectional view of the optical cable radially cut with the convex strip of this application set as an arc shape;

[0029] Figure 2 is a cross-sectional view of the optical cable radially cut when the protrusion of this application is set as a trapezoid;

[0030] Figure 3 is a schematic diagram of the structure of the fiber ribbon formed by the combination of several optical fibers and adhesive parts in this application;

[0031] Figure 4 is a schematic diagram of the structure of the optical fiber ribbon and a water-blocking yarn bound together with colored thread to form an optical fiber bundle in this application.

[0032] Figure 5 is a schematic diagram showing the specific correspondence of each physical quantity in this application on the surface of the optical cable.

[0033] In the diagram: 1. Cable core; 11. Optical fiber; 12. Adhesive joint; 13. Water-blocking yarn; 14. Colored thread; 15. Optical fiber ribbon; 16. Optical fiber bundle; 2. Water-blocking tape; 3. Outer sheath; 4. Reinforcing member; 5. Raised strip. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are some, but not all, of the embodiments of this application. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0035] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this application 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, and therefore should not be construed as a limitation on the scope of protection of this application. The embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0036] It should be understood that the accompanying drawings are for illustrative purposes only.

[0037] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. These drawings are simplified schematic diagrams, which are only used to illustrate the basic structure of the present application and therefore only show the components relevant to the present application.

[0038] An air-blown optical cable, as shown in Figures 1-5, includes a cable core 1 and an outer sheath 3 covering the cable core 1.

[0039] As shown in Figure 3, the cable core 1 includes a plurality of optical fibers 11 and adhesive portions 12 that intermittently bond the plurality of optical fibers 11 in the axial direction. Any adhesive portion 12 on any optical fiber 11 is a first reference adhesive portion, an adjacent adhesive portion 12 on an optical fiber 11 adjacent to the first reference adhesive portion is a second reference adhesive portion, and an adjacent adhesive portion 12 on an optical fiber 11 adjacent to the second reference adhesive portion is a third reference adhesive portion. The first reference adhesive portion, the second reference adhesive portion, and the third reference adhesive portion are on the same straight line. For example, three optical fibers 11 are arranged in sequence as the first optical fiber, the second optical fiber, and the third optical fiber. Each optical fiber 11 has three adhesive portions 12, arranged in sequence as the first adhesive portion, the second adhesive portion, and the third adhesive portion. The first adhesive portion on the second optical fiber is defined as the first reference adhesive portion. The optical fibers adjacent to the first reference adhesive portion are the first optical fiber and the third optical fiber. The adhesive portions adjacent to the first reference adhesive portion are the first adhesive portions of the first optical fiber and the first adhesive portions of the third optical fiber. The two first adhesive portions are the second reference adhesive portions. If there is a fourth optical fiber, the optical fiber adjacent to the second reference adhesive portion is the fourth optical fiber. The first adhesive portion adjacent to the second reference adhesive portion is the first adhesive portion of the fourth optical fiber. This first adhesive portion is the third reference adhesive portion. The first reference adhesive portion, the second reference adhesive portion, and the third reference adhesive portion are on the same straight line, that is, the first adhesive portions of the first optical fiber, the second optical fiber, the third optical fiber, and the fourth optical fiber are on the same straight line.

[0040] The high-precision dispensing technology used in the fiber optic ribbon 15 ensures that the connecting lines of adjacent adhesive portions 12 of any adjacent fiber 11 are on the same straight line. In this design, the adhesive portions 12 are set as adhesive dots with a deviation of less than 0.1 mm between them. This high precision helps ensure that the cross-sectional differences between several fibers 11 after cutting are minimal during the overall fusion splicing process of the fiber optic ribbon 15, maximizing the stability of the fusion splicing performance and reducing fusion loss.

[0041] In this scheme, the bare optical fiber size is set between 230μm and 240μm. After the optical fiber 11 is colored, the size of the optical fiber 11 is between 235μm and 245μm. Then, a layer of resin is coated on the surface of the optical fiber 11, and the size of the optical fiber 11 after coating with resin is between 240μm and 250μm.

[0042] The adhesive length of fiber 11, D2, is 20±5mm, and the adhesive distance of fiber 11, D3, is 40±5mm. The tilted dimension, D4, is exactly D4 = D2 * (number of fibers 11 - 1). The overall width of the fiber bundle 16, D1, is equal to the resin-coated dimension of fiber 11 * N + (40~60μm), where 40~60μm is a correction factor, representing the tiny gaps directly existing in fiber 11, providing higher mobility and resistance to external forces. Compared to fiber ribbons 15 bonded with traditional adhesive dots, this method achieves the same strength with smaller adhesive dots; if the same dot size is used, even greater strength can be obtained.

[0043] The fiber optic ribbon 15, employing a dispensing structure, ensures a tight bond between the optical fibers 11 with minimal adhesive usage. Traditional fiber optic ribbons 15, using full resin coating, suffer from overall structural curing, leading to breakage during winding and thus occupying space within the optical cable. The fiber optic ribbon 15 disclosed in this solution can be wound into a single strand of optical fibers 11 or twisted in less than one revolution, significantly enhancing its flexibility, drastically reducing the space required, and providing a smaller bending radius.

[0044] As shown in Figure 4, two colored wires 14 are arranged around several optical fibers 11. The two colored wires 14 are twisted in opposite directions to bundle the optical fibers 11 into a bundle. The optical fibers 11 are bonded together to form an optical fiber ribbon 15. The two colored wires 14 can bundle only one optical fiber ribbon 15 or multiple optical fiber ribbons 15. One or more optical fiber ribbons 15 and a water-blocking yarn are combined and twisted by the two colored wires to form an optical fiber bundle 16. A water-blocking yarn 13 is arranged inside the optical fiber bundle 16. The water-blocking yarn 13 is made of high-expansion water-blocking yarn. The colored wires 14 bundle one or more optical fiber ribbons 15 and a water-blocking yarn 13 to form an optical fiber bundle 16. Several optical fiber bundles 16 are twisted into a cable core 1. Prepare one or more optical fiber ribbons 15 and a high-expansion water-blocking yarn, and then prepare two colored wires 14. Wrap one or more optical fiber ribbons 15 and a water-blocking yarn 13 by twisting in opposite directions. The color thread 14 is made of 111D polyester yarn, which can be designed in different colors as required to facilitate the differentiation of different fiber bundles 16. The fiber ribbons 15 within any bundle can be distinguished by inkjet markings. Setting the pitch of the color thread 14 winding to less than 7cm allows for better direct differentiation of the fiber bundles 16. Traditionally, fiber bundles 16 often only have surface markings on the fiber ribbons 15. However, when inkjet marking is used as the primary identification method, it becomes difficult to quickly distinguish individual fiber bundles 16 as the core count increases. The different colored yarns in this solution allow construction personnel to quickly separate different fibers based on the color thread 14, significantly improving the splicing efficiency of ultra-high core count fiber bundles 16.

[0045] As shown in Figures 1 and 2, to reduce friction during air-blowing installation of the optical cable into the external duct, a raised strip 5 is provided on the outer wall of the outer sheath 3. The height of the raised strip 5 extends radially outward along the optical cable, and the length of the raised strip 5 extends axially along the air-blown optical cable, spiraling around the outer surface of the outer sheath 3. If the raised strip 5 is not spirally arranged, the air-blowing installation effect is poor. To ensure air-blowing installation of the optical cable when entering the external duct, the raised strip 5 spirals around the surface of the outer sheath, and the pitch of the spiral raised strip 5 is set to be less than or equal to 0.5m. When the pitch is greater than 0.5m, the air-blowing installation efficiency is poor. Furthermore, when the pitch of the spiral raised strip 5 is set to 0.01-0.5m, there is only one raised strip 5 on any radial surface of the optical cable, resulting in a better air-blowing effect.

[0046] A protruding strip 5 is provided on the outer sheath 3. The protruding strip 5 is provided on the entire outer surface of the optical cable. The protruding strip 5 can reduce the friction between the optical cable and the sheath during the laying process and improve the laying efficiency.

[0047] Setting the protrusions 5 can reduce the contact area between the optical cable and the external pipe, thereby reducing the friction in the pipe and making it suitable for air blowing applications. The principle is that if the outer sheath 3 is a complete surface in contact with the pipe, it is difficult to avoid unevenness on the surface of the outer sheath 3. The increased roughness of the outer sheath 3 surface will bring greater friction. After setting the friction protrusions, the surface contact is changed to a linear contact, and the number of points that can generate friction is greatly reduced. At the same time, during the air blowing process, the friction surface of the airflow on the optical cable can also be increased, which is conducive to the airflow lifting the optical cable in the pipe, reducing the interface pressure and reducing friction.

[0048] As shown in Figure 5, during air-blowing installation of optical cables, the gas travels along the spiral direction of the convex strip, generating a thrust component on the optical cable in the axial direction. This pushes the optical cable into the external duct. Regardless of the thrust, given sufficient time, the optical cable can be laid within the duct. However, when the thrust is small, laying the optical cable is time-consuming, labor-intensive, and yields poor results. To ensure the efficiency of air-blowing installation, the thrust component propelling each meter of optical cable by the thrust component is defined as F. f When the force is set to be greater than 50N, and the optical cable is set to 1 meter, the driving force F f The driving force F is greater than 50N when the optical cable is set to 5 meters. f When the force F is greater than 250N and the optical cable is set to 10 meters, the driving force is F. f Greater than 500N, and so on.

[0049] When the driving force per meter of optical cable is greater than 50N, the laying speed of the optical cable is fast and the laying effect is good. f The calculation formula is: F f =S·μ(θ)·P P ·h;

[0050] in: μ(θ) = μ·sinθ;

[0051] F f During the air blowing process, the pushing force on a specific length of optical cable, generated by the friction between the optical cable and the gas, is the pushing force on the optical cable along the direction of its movement. The larger the value, the better it is for improving the air blowing effect of the optical cable. However, this value is limited by the processing technology, pipe size, and other physical properties of the optical cable, and cannot be increased indefinitely.

[0052] S is the total length of the 5th ridge after it is unfolded along the circumference of the optical cable. Under air blowing conditions, the length of the ridge inside the optical cable can be increased to increase the contact with high-pressure air.

[0053] μ(θ) is the compound friction multiplier, which is the effect of the frictional force pushed by the air along the axial direction of the optical cable under a given outer sheath 3 material and helical direction. It is a function defined by the friction coefficient of the specific outer sheath 3 material and the acute angle θ between the helical protrusion 5 and the axial direction of the optical cable. μ is the dynamic friction coefficient of the given outer sheath 3 material under this working condition. When the outer sheath 3 material is determined, the final calculation result μ(θ) can be converted into a function of the pitch p.

[0054] r is the radius of the optical cable sheath;

[0055] p is the pitch, which represents the distance between the two closest spiral protrusions 5 on any plane passing through the geometric center of the optical cable;

[0056] L is the total length of the optical cable;

[0057] θ is the angle between the spiral protrusion 5 and the axial direction of the optical cable;

[0058] μ is the coefficient of dynamic friction of the given outer sheath material 3 under this working condition;

[0059] P P Given the pressure inside the pipe under the air blowing equipment and pipe, the air blowing process is considered as a process with constant pressure inside the pipe;

[0060] h is the height of the convex strip 5.

[0061] The detailed calculation steps are as follows:

[0062] The length of the spiral rib within one pitch is: s 2 =2πr 2 +p 2 ,

[0063] so,

[0064] A fiber optic cable has a length of L and contains n pitches. Therefore, when the length of the fiber optic cable is L,

[0065] Therefore, within a fiber optic cable segment of length L, the total length of the protrusions is: S = s·n.

[0066] Furthermore,

[0067] Furthermore,

[0068] Furthermore,

[0069] In traditional research, controlling the driving force on optical cables during air-blown deployment requires additional equipment and multiple tests, involving numerous variables. Each addition or modification of a parameter (such as rib height, rib width, rib shape, sheath material, etc.) necessitates the creation of new samples. This process is time-consuming and labor-intensive, and most of the produced samples ultimately have to be scrapped.

[0070] With quantitative mathematical calculations, once specific parameters are fixed according to product requirements, the most suitable production parameters can be directly calculated based on the formula. Only a few parameters within a reasonable range need to be sampled and tested to obtain the optimal solution, which can significantly reduce costs, reduce waste, and improve work efficiency.

[0071] For ease of calculation, the parameters of the test sample are as follows:

[0072] The radius r of the outer sheath 3 of the optical cable is 0.1m, the total length L of the optical cable is 1m, the dynamic friction system μ is 0.5, the height h of the convex strip 5 is 0.1mm, and the internal pressure P is... P Take 1013250 Pa (10 standard atmospheres).

[0073] The following table was obtained after calculation.

[0074] In this scheme, with the height of convex strip 5 set to 0.1, F f To achieve the desired air-blowing deployment efficiency, the required N needs to be maintained above 50N. Therefore, in the last set of data in the table, when the pitch P is set to 1m and the height h of the convex strip 5 is set to 0.1mm, the driving force F... f The current is less than 50N, therefore it cannot achieve the desired effect of this solution and is not feasible.

[0075] The greater the driving force, the better. However, if the driving force is too large, the pitch of the spiral ridge 5 will be smaller. If the pitch of the spiral ridge 5 is too small, production will be impossible. Therefore, to achieve the optimal laying effect of air-blown optical cable, the driving force per meter of optical cable should be greater than 50N, and the pitch of the spiral ridge 5 should be less than or equal to 0.5m. Furthermore, when the pitch of the spiral ridge 5 is set to 0.01-0.5m, there is only one ridge on any radial surface of the optical cable, resulting in a better air-blowing effect.

[0076] On any radial surface of the air-blown optical cable, the protrusion 5 is either arc-shaped or trapezoidal. When the cross-sectional shape of the protrusion 5 is set to trapezoidal, the size of the protrusion 5 is larger the closer it is to the outer sheath 3, ensuring the air-blowing effect. The shape of the protrusion 5 is often arc-shaped or trapezoidal, but it can also be set to other shapes, as long as it can pass through the sizing die. However, setting it to other shapes may cause deformation and other problems. For example, a triangle, due to its pointed head, will cause scraping and indentation after entering the sizing die. If it is a square or rectangle, the angles on both sides are 90°, which is very easy to cause scraping, eventually causing the protrusion 5 to be flattened. At the same time, when the optical cable is laid to the external duct, the air-blowing effect is best when the shape of the protrusion 5 is set to arc-shaped or trapezoidal.

[0077] To enhance the strength of the optical cable, a reinforcing member 4 is provided inside the outer sheath 3. The reinforcing member 4 is evenly distributed circumferentially inside the outer sheath 3. Because the reinforcing member 4 is arranged in a circular pattern, the existing reinforcing member 4 results in poor bending performance of the optical cable. After the winding and bending are completed during production, it is prone to plastic deformation or flexural deformation and is prone to twisting during air blowing. In order to further ensure the bending performance of the optical cable, in this solution, the reinforcing member 4 is set as an aramid fiber rod or a glass fiber rod. The size of the reinforcing member 4 is between 0.3mm and 0.6mm, and the number is set to 8-16 rods evenly distributed around the outer sheath 3.

[0078] The outer sheath 3 is made of low-friction medium-density polyethylene material. Polyethylene material has good low-temperature resistance and stable chemical properties.

[0079] In this design, the rigidity of the optical cable is set to 0.45-0.85 N·m. 2 The average range of the pipe friction force of the optical cable is set between 90N and 150N, while the maximum range of the pipe friction force is set between 100N and 200N.

[0080] This application addresses the deficiencies in the prior art and has the following beneficial effects: A raised strip 5 is provided on the outer side of the outer sheath 3 to reduce the friction between the optical cable and the outer duct during installation, ensuring the successful installation of the air-blown optical cable; simultaneously, the pushing force F of the gas-driven optical cable is controlled. f With a driving force greater than 50N per meter, the optical cable can be laid more quickly and efficiently, saving time and labor. To ensure production, the pitch of the spiral convex strip 5 is set to less than or equal to 0.5m when the driving force of the optical cable is greater than 50N per meter.

[0081] Based on the preferred embodiments of this application, and through the above description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

[0082] The preferred embodiments of this application have been described in detail above with reference to the accompanying drawings. However, this application is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this application, various simple modifications can be made to the technical solution of this application, and these simple modifications all fall within the protection scope of this application.

[0083] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this application will not describe the various possible combinations separately.

[0084] Furthermore, various different implementations of this application can be combined in any way, as long as they do not violate the spirit of this application, they should also be regarded as the content disclosed in this application.

Claims

1. An air-blown optical cable, characterized in that: The cable includes a cable core (1) and an outer sheath (3) covering the cable core (1). A protruding strip (5) is provided on the outer wall of the outer sheath (3). The height direction of the protruding strip (5) extends outward along the radial direction of the optical cable, and the length direction of the protruding strip (5) extends along the axial direction of the air-blown optical cable and spirals around the outer surface of the outer sheath (3). The gas advances along the spiral direction of the protruding strip (5) and generates a thrust component on the optical cable in the axial direction. The thrust component drives the optical cable to move by a driving force F per meter of optical cable. f Greater than 50N, driving force F f The calculation formula is: F f =S·μ(θ)·P P ·h; in: μ(θ)=μ·sinθ; F f The radial thrust experienced by the optical cable during the air blowing process; S is the total length of the convex strip (5) after it is unfolded along the circumference of the optical cable from the starting point; μ(θ) is the compound friction multiplier; r is the radius of the optical cable sheath; p is the pitch; L is the total length of the optical cable; θ is the acute angle between the spiral protrusion (5) and the axial direction of the optical cable; P P Given the pressure inside the pipe of the air blowing device and pipeline; h is the height of the convex strip (5).

2. The air-blown optical cable according to claim 1, characterized in that: The pitch of the spiral rib (5) is set to be less than or equal to 0.5m.

3. The air-blown optical cable according to claim 2, characterized in that: The pitch of the spiral rib (5) is set to 0.01-0.5m.

4. The air-blown optical cable according to claim 1, characterized in that: On any radial surface of the air-blown optical cable, the cross-section of the protrusion (5) is arc-shaped or trapezoidal; when the cross-section of the protrusion (5) is set to trapezoidal, the closer it is to the outer sheath (3), the larger the cross-sectional size of the protrusion (5).

5. The air-blown optical cable according to claim 1, characterized in that: A reinforcing member (4) is provided inside the outer sheath (3), and the reinforcing member (4) is evenly arranged circumferentially inside the outer sheath (3).

6. The air-blown optical cable according to claim 5, characterized in that: The reinforcing member (4) is configured as an aramid fiber rod or a glass fiber rod.

7. The air-blown optical cable according to claim 1, characterized in that: The outer sheath (3) is made of polyethylene.

8. The air-blown optical cable according to claim 1, characterized in that: The cable core (1) includes a plurality of optical fibers (11) and an adhesive portion (12) for intermittently bonding the plurality of optical fibers (11) in the axial direction. Two colored wires (14) are provided outside the plurality of optical fibers (11), and the two colored wires (14) are wrapped in opposite directions to bundle the plurality of optical fibers (11) into a bundle.

9. The air-blown optical cable according to claim 8, characterized in that: Any adhesive portion on any optical fiber is a first reference adhesive portion, an adjacent adhesive portion on an optical fiber adjacent to the first reference adhesive portion is a second reference adhesive portion, and an adjacent adhesive portion on an optical fiber adjacent to the second reference adhesive portion is a third reference adhesive portion. The first reference adhesive portion, the second reference adhesive portion, and the third reference adhesive portion are on the same straight line.

10. The air-blown optical cable according to claim 1, characterized in that: The rigidity of the air-blown optical cable is set to 0.45-1.85 N·m. 2 .

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