An air blown optical cable

Abstract

The present invention discloses a blown optical cable, which includes a cable core and an outer sheath covering the cable core. A rib is provided on the outer wall of the outer sheath. The height direction of the rib extends radially outward along the optical cable, and the length direction of the rib extends along the axial direction of the blown optical cable and spirally surrounds the outer surface of the outer sheath. The gas advances along the spiral direction of the rib, generating a thrust component acting on the optical cable in the axial direction, and the thrust component pushes the optical cable to move with a driving force F per meter f is greater than 50N. A rib is provided on the outer side of the outer sheath to reduce the friction when the optical cable is laid in the outer pipeline, ensuring the completion of the laying of the blown optical cable; at the same time, the driving force F for the gas to push the optical cable to move is controlled f is greater than 50N per meter, enabling the more rapid and stable completion of the laying of the optical cable, saving time and effort.

Description

Technical Field

[0001] The present invention relates to an optical cable product, and more particularly to a blown optical cable. Background Art

[0002] Blown optical cable is a technology that uses compressed gas (usually air) to blow an optical cable or cable through the inside of a pipeline. This technology is mainly used for optical fiber wiring or cable wiring, especially in places where manual laying is difficult, such as long-distance underground pipelines. Blown optical cable has the advantages of high-efficiency cable laying, reduced damage, long-distance cable laying, reduced labor intensity, strong scalability, etc., so it is widely used in the telecommunications industry and other fields that require long-distance cable laying, especially in the construction of optical fiber networks.

[0003] However, the current blown optical cable has a low laying efficiency and cannot complete the laying of the 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

[0004] The present invention overcomes the deficiencies of the prior art and provides a blown optical cable.

[0005] To achieve the above object, the technical solution adopted by the present invention is: a blown optical cable, comprising a cable core and an outer sheath covering the cable core. A convex strip is provided on the outer wall of the outer sheath. The height direction of the convex strip extends radially outward along the optical cable, and the length direction of the convex strip extends along the length direction of the blown optical cable and is spirally wound around the outer surface of the outer sheath. The gas advances along the spiral direction of the convex strip, generating a thrust component on the optical cable in the axial direction. The thrust component F that pushes each meter of the optical cable to move f is greater than 50 N per meter. The thrust F f is calculated by the formula:

[0006] ;

[0007] wherein:

[0008] ;

[0009] ;

[0010] ;

[0011] F f is the thrust force received by the optical cable during the blowing process;

[0012] S is the total length after the starting point of the convex strip is unfolded along the circumference direction of the optical cable;

[0013] is the composite friction multiplier;

[0014] r is the radius of the cable sheath;

[0015] p is the pitch;

[0016] L is the total length of the optical cable;

[0017] θ is the acute angle between the helical rib and the axial direction of the optical cable;

[0018] P P is the internal pressure in the pipe under a given air blowing device and pipeline;

[0019] h is the height of the rib.

[0020] More specifically, the pitch of the helical rib is set to be less than or equal to 0.5 m.

[0021] More specifically, the pitch of the helical rib is set to be 0.01 - 0.5 m.

[0022] More specifically, on any radial plane of the air blown optical cable, the shape of the rib is set to be arc-shaped or trapezoidal.

[0023] More specifically, a strengthening member is provided inside the outer sheath, and the strengthening member is circumferentially and uniformly arranged inside the outer sheath.

[0024] More specifically, the strengthening member is set to be an aramid fiber rod or a glass fiber rod.

[0025] More specifically, the outer sheath is made of polyethylene material.

[0026] More specifically, the cable core includes a plurality of optical fibers and an adhesive part that adhesively bonds the plurality of optical fibers intermittently in the axial direction. Two color wires are arranged outside the plurality of optical fibers, and the two color wires are wound in opposite directions to bundle the plurality of optical fibers into a bundle.

[0027] More specifically, any adhesive part on any optical fiber is a first reference adhesive part, the adjacent adhesive part on the optical fiber adjacent to the first reference adhesive part is a second reference adhesive part, and the adjacent adhesive part on the optical fiber adjacent to the second reference adhesive part is a third reference adhesive part. The first reference adhesive part, the second reference adhesive part, and the third reference adhesive part are on the same straight line.

[0028] More specifically, the rigidity of the air blown optical cable is set to be 0.45 - 1.85 N·m 2 .

[0029] The present invention solves the defects existing in the background art, and the present invention has the following beneficial effects: ribs are provided on the outer side of the outer sheath, reducing the friction when the optical cable is laid with the outer pipeline, ensuring the completion of the laying of the air blown optical cable; at the same time, controlling the driving force F for the gas to push the optical cable to move fGreater than 50 N per meter, it can complete the laying of the optical cable more quickly, smoothly, saving time and effort. Brief Description of the Drawings

[0030] The present invention will be further described below in conjunction with the drawings and embodiments;

[0031] Figure 1 It is a cross-sectional view taken along the radial direction of the optical cable with the raised strip of the present invention set as an arc;

[0032] Figure 2 It is a cross-sectional view taken along the radial direction of the optical cable with the raised strip of the present invention set as a trapezoid;

[0033] Figure 3 It is a schematic structural view of several optical fibers and an adhesive part of the present invention cooperating to form an optical fiber ribbon;

[0034] Figure 4 It is a schematic structural view of an optical fiber ribbon and a water blocking yarn of the present invention bundled by a color thread to form an optical fiber bundle;

[0035] Figure 5 It is a schematic view of the specific corresponding situation of each physical quantity on the surface of the optical cable of the present invention;

[0036] In the figure: 1. Cable core; 11. Optical fiber; 12. Adhesive part; 13. Water blocking yarn; 14. Color thread; 15. Optical fiber ribbon; 16. Optical fiber bundle; 2. Water blocking tape; 3. Outer sheath; 4. Reinforcing member; 5. Raised strip. Detailed Embodiments

[0037] To make the purpose, technical solution and advantages of the implementation of the present invention clearer, the technical solutions in the embodiments of the present invention will be described in more detail below in conjunction with the drawings in the embodiments of the present invention. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions from beginning to end. The described embodiments are some, but not all, of the embodiments of the present invention. The embodiments described below by referring to the drawings are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

[0038] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "center", "longitudinal", "lateral", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings. These are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as limiting the protection scope of the present invention. The embodiments of the present invention will be described in detail below with reference to the drawings.

[0039] It should be understood that the drawings are only used for exemplary illustration of the present application.

[0040] Now, the present invention will be further described in detail with reference to the drawings and embodiments. These drawings are all simplified schematic diagrams, only showing the basic structure of the present invention in a schematic manner, so they only show the components related to the present invention.

[0041] An air-blown optical cable, as Figures 1 - 5 shown, includes a cable core 1 and an outer sheath 3 covering the cable core 1.

[0042] As Figure 3 shown, the cable core 1 includes a plurality of optical fibers 11 and an adhesive part 12 that adhesively bonds the plurality of optical fibers 11 intermittently in the axial direction. Any adhesive part 12 on any optical fiber 11 is a first reference adhesive part, the adjacent adhesive part 12 on the optical fiber 11 adjacent to the first reference adhesive part is a second reference adhesive part, and the adjacent adhesive part 12 on the optical fiber 11 adjacent to the second reference adhesive part is a third reference adhesive part. The first reference adhesive part, the second reference adhesive part, and the third reference adhesive part are on the same straight line. For example, three optical fibers 11 are provided, which are sequentially the first optical fiber, the second optical fiber, and the third optical fiber. Three adhesive parts 12 are provided on each optical fiber 11, which are sequentially the first adhesive part, the second adhesive part, and the third adhesive part. The first adhesive part on the second optical fiber is defined as the first reference adhesive part. The optical fibers adjacent to the first reference adhesive part are the first optical fiber and the third optical fiber. The adhesive parts adjacent to the first reference adhesive part are the first adhesive parts of the first optical fiber and the third optical fiber. The two first adhesive parts are the second reference adhesive parts. If there is also a fourth optical fiber, the optical fiber adjacent to the second reference adhesive part is the fourth optical fiber, and the adjacent part to the second reference adhesive part is the first adhesive part of the fourth optical fiber. This first adhesive part is the third reference adhesive part. The first reference adhesive part, the second reference adhesive part, and the third reference adhesive part are on the same straight line, that is, the first adhesive parts of the first optical fiber, the second optical fiber, the third optical fiber, and the fourth optical fiber are on the same straight line.

[0043] The high-precision dispensing technology adopted by the optical fiber ribbon 15 makes the connection lines of the adjacent bonding parts 12 of any adjacent optical fibers 11 all on the same straight line. In this solution, the bonding part 12 is set as a glue dot, and the deviation between each other is less than 0.1 mm. High precision is beneficial to ensuring that during the overall fusion splicing process of the optical fiber ribbon 15, after several optical fibers 11 are cut, the gap between the cross-sections is extremely small, maximizing the stability of the fusion splicing performance and being beneficial to reducing the fusion splicing loss.

[0044] In this solution, the size of the bare optical fiber is set between 230 μm and 240 μm. After the optical fiber 11 is colored, the size of the optical fiber 11 is between 235 μm and 245 μm. Then, a layer of resin is coated on the surface of the optical fiber 11. After the resin is coated, the size of the optical fiber 11 is between 240 μm and 250 μm.

[0045] The dispensing length D2 of the optical fiber 11 is D2 = 20 ± 5 mm, the dispensing distance D3 of the optical fiber 11 is D3 = 40 ± 5 mm, and the D4 size under inclination is just D4 = D2 * (number of optical fibers 11 - 1). The overall width D1 of the optical fiber bundle 16 is D1 = size of the optical fiber 11 after resin coating * N + (40 - 60 μm), where 40 - 60 μm is the correction coefficient, that is, the tiny gap directly existing in the optical fiber 11, providing higher mobility and external force resistance for the optical fiber 11. Compared with the optical fiber ribbon 15 bonded by traditional glue dots, the same strength can be achieved with smaller glue dots. If the same glue dot size is adopted, greater strength can be obtained.

[0046] The optical fiber ribbon 15 with a dispensing structure can ensure the tight bonding between the optical fibers 11 with a very small amount of glue used. The traditional optical fiber ribbon 15 adopts a full resin coating, which will cause the overall structure of the optical fiber ribbon 15 to solidify, and once wound, the optical fiber ribbon 15 will be damaged, so it occupies a fixed space in the optical cable; the optical fiber ribbon 15 disclosed in this solution can wind the overall optical fibers 11 into one strand, or can be twisted less than one week, greatly enhancing its flexibility, significantly reducing the space required by the optical fiber ribbon 15, and providing a smaller bending radius.

[0047] Such as Figure 4As shown, two color threads 14 are arranged outside several of the optical fibers 11. The two color threads 14 are wound in opposite directions to bundle several of the optical fibers 11 into a bundle. Several of the optical fibers 11 are bonded to form an optical fiber ribbon 15. The two color threads 14 can bundle only one optical fiber ribbon 15, or can bundle multiple ones. One or more optical fiber ribbons 15 and a water-blocking yarn are combined and wound by two color threads 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 uses a high-expansion water-blocking yarn. The color threads 14 bundle one or several optical fiber ribbons 15 and a water-blocking yarn 13 to form an optical fiber bundle 16. Several optical fiber bundles 16 are stranded to form a cable core 1. Prepare one or several optical fiber ribbons 15 and a high-expansion water-blocking yarn, and then prepare two color threads 14. Wind and tie one or several optical fiber ribbons 15 and a water-blocking yarn 13 in an opposite winding manner. The color threads 14 use 111D polyester yarn. The polyester yarn can be designed into different colors according to requirements to facilitate the distinction of different optical fiber bundles 16. For the optical fiber ribbons 15 in any bundle, they can be distinguished by spraying identification marks. Set the pitch of the winding of the color threads 14 to be less than 7 cm. Making the pitch of the winding of the color threads 14 into a small pitch can better distinguish between optical fiber bundles 16. In traditional optical fiber bundles 16, there is often only inkjet coding on the surface of the optical fiber ribbon 15. When inkjet coding is used as the main identification method, it is difficult to quickly distinguish each optical fiber bundle 16 when the core number increases. In this solution, the yarns of different colors can enable construction personnel to quickly separate different optical fibers according to the color threads 14, greatly improving the splicing efficiency of optical fiber bundles 16 with a super-large core number.

[0048] As Figure 1 , Figure 2 shown, to reduce the friction when the optical cable is blown and laid into an external pipeline, a rib 5 is arranged on the outer wall of the outer sheath 3. The height direction of the rib 5 extends radially outward along the radial direction of the optical cable. The length direction of the rib 5 extends along the axial direction of the blown optical cable and spirally surrounds the outer surface of the outer sheath 3. If the rib 5 is not spirally arranged, the effect of blown laying is not good. To ensure the blown laying of the optical cable when it enters the external pipeline, the rib 5 spirally surrounds the surface of the outer sheath. The pitch of the spiral rib 5 is set to be less than or equal to 0.5 m. When the pitch is greater than 0.5 m, the efficiency of blown laying is not good. Further, when the pitch of the spiral rib 5 is set to 0.01 - 0.5 m, on any radial plane of the optical cable, there is only one rib 5, and the blowing effect is better.

[0049] A rib 5 is prominently arranged on the outer sheath 3. The rib 5 is arranged on the outer surface of the entire optical cable. Arranging the rib 5 can reduce the friction between the optical cable during laying and the sheath, and improve the laying efficiency.

[0050] The provision of the raised strips 5 can reduce the contact area between the optical cable and the external pipe, thereby reducing the frictional force within the pipe and thus adapting to air blowing applications. The principle lies in that if the entire outer sheath 3 surface contacts the pipe, it is difficult to avoid unevenness on the microscopic surface of the outer sheath 3. The increased roughness of the outer sheath 3 surface will bring greater frictional force. After setting the friction bumps, the surface contact is transformed into line contact, and the points where friction can occur are greatly reduced. At the same time, during the air blowing process, the frictional surface of the air flow on the optical cable can also be increased, which is conducive to the air flow lifting the optical cable in the pipe, reducing the interface pressure and minimizing the frictional force.

[0051] As Figure 5 shown, when blowing and laying the optical cable, the gas advances along the spiral direction of the raised strips, generating a thrust component in the axial direction on the optical cable to push the optical cable into the external pipe. Regardless of the magnitude of the driving force, as long as the time is sufficient, the optical cable can be laid in the pipe. However, when the driving force is small, the laying of the optical cable is time-consuming and laborious, and the laying effect is not good. To ensure the efficiency of air blowing laying, the driving force F f for pushing each meter of the optical cable to move is set to be greater than 50 N. When the optical cable is set to 1 meter, the driving force F f is greater than 50 N. When the optical cable is set to 5 meters, the driving force F f is greater than 250 N. When the optical cable is set to 10 meters, the driving force F f is greater than 500 N, and so on.

[0052] When the driving force on each meter of the optical cable is greater than 50 N, the laying speed of the optical cable is fast and the laying effect is good. The calculation formula for the driving force F f is:

[0053] ;

[0054] Where:

[0055] ;

[0056] ;

[0057] ;

[0058] F f is the driving force generated by the friction between the optical cable and the gas on a specific length of the optical cable during the air blowing process, along the movement direction of the optical cable, that is, the driving force received by the optical cable. The larger its value, the more conducive it is to improving the air blowing effect of the optical cable. However, this value is limited by processing technology, pipe size, and other physical properties of the optical cable and cannot increase infinitely;

[0059] S is the total length after the starting point of the rib 5 is unfolded along the circumference of the optical cable. Under the condition of air blowing, it is the length of the protrusions inside the optical cable that can be used to increase the contact with the high-pressure air;

[0060] is the composite friction multiplier. Under the given outer sheath 3 material and helix direction, it represents the pushing effect of the frictional force of the air-pushed optical cable in the axial 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 rib 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 can be converted into a function of the pitch p;

[0061] r is the radius of the optical cable sheath;

[0062] p is the pitch, which represents the distance between the two closest helical ribs 5 on any plane passing through the geometric center of the optical cable;

[0063] L is the total length of the optical cable;

[0064] θ is the angle between the helical rib 5 and the axial direction of the optical cable;

[0065] μ is the dynamic friction coefficient of the given outer sheath 3 material under this working condition;

[0066] P P is the internal pressure in the pipe under the given air blowing equipment and pipeline. The air blowing process is regarded as a process with a constant internal pressure in the pipe;

[0067] h is the height of the rib 5.

[0068] The detailed calculation steps are as follows:

[0069] The length of the helical rib within one pitch is: s 2 = 2πr 2 + p 2 ,

[0070] So, s = ,

[0071] The length of a section of the optical cable is L, and there are n pitches within a section of the optical cable. So when the length of the optical cable is L, n = ,

[0072] So, within a section of the optical cable with a length of L, the total length of the protrusions is: S = s·n,

[0073] Further, ,

[0074] Further, ,

[0075] Furthermore, ,

[0076] In traditional research, to control the driving force on the optical cable during air blowing laying, additional equipment needs to be added and multiple tests are required, and multiple variables are involved. Every time a parameter is added or modified (such as rib height, rib width, rib shape, sheath material, etc.), new samples need to be made. This is time-consuming and laborious, and most of the produced samples can only be scrapped in the end.

[0077] Now, through mathematical calculations using quantitative formulas, after fixing specific parameters according to product requirements, the most suitable production parameters can be directly deduced from the formulas. 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.

[0078] For the convenience of calculation, the parameters of the test samples are as follows:

[0079] The radius r of the outer sheath 3 of the optical cable is 0.1 m, the total length L of the optical cable is 1 m, the dynamic friction coefficient μ is 0.5, the height h of the rib 5 is 0.1 mm, and the pressure P inside the pipe P is 1013250 Pa (10 standard atmospheres).

[0080] The following table is obtained through calculation

[0081]

[0082] In this solution, when the height of the rib 5 is 0.1, F f needs to be maintained above 50 N to successfully achieve the air blowing laying efficiency desired in this solution. Therefore, in the last set of data in the table, when the pitch P is set to 1 m and the height h of the rib 5 is set to 0.1 mm, the driving force F f is less than 50 N, so the desired effect of this solution cannot be achieved and it is not feasible.

[0083] The greater the set driving force, the better, but when the driving force is too large, the pitch of the spiral rib 5 becomes smaller. However, when the pitch of the spiral rib 5 is too small, production is impossible. Therefore, to achieve the optimal laying effect of the air blown optical cable, the driving force per meter of the optical cable is greater than 50 N, and the pitch of the spiral rib 5 is set to be less than or equal to 0.5 m. Further, when the pitch of the spiral rib 5 is set to 0.01 - 0.5 m, there is only one protrusion on any radial plane of the optical cable, and the air blowing effect is better.

[0084] On any radial plane of the air-blown optical cable, the shape of the rib 5 is arc-shaped or trapezoidal. When the cross-sectional shape of the rib 5 is trapezoidal, the closer it is to the outer sheath 3, the larger the size of the rib 5, ensuring the air-blowing effect. The shape of the rib 5 is often arc-shaped or trapezoidal, and 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 problems such as deformation. For example, in the case of a triangle, due to the overly sharp head, it will cause scraping and result in depressions after entering the sizing die. If it is a square or rectangle, since the angles on both sides are 90°, it is extremely easy to cause scraping, and finally the rib 5 will be smoothed. At the same time, for the air-blowing laying effect when the optical cable is laid in an external pipeline, the air-blowing effect is the best when the shape of the rib 5 is set to arc-shaped or trapezoidal.

[0085]

[0086] To enhance the strength of the optical cable, a reinforcing member 4 is provided inside the outer sheath 3. The reinforcing member 4 is circumferentially and uniformly arranged inside the outer sheath 3. Due to the circumferential laying mode of the reinforcing member 4, the existing reinforcing member 4 makes the bending performance of the optical cable poor. After winding and bending during production, it is prone to plastic deformation or flexural deformation, and it is prone to torsion during the air-blowing process. 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 0.3 mm and 0.6 mm, and the number is set to 8 - 16 and evenly distributed around the outer sheath 3.

[0087] The outer sheath 3 is made of low-friction medium-density polyethylene material, and the polyethylene material has good low-temperature resistance and stable chemical properties.

[0088] In this solution, the rigidity range of the optical cable is set to 0.45 - 0.85 N·m 2 , the average value range of the pipeline friction force of the optical cable is between 90 N and 150 N, and the maximum value range of the pipeline friction force of the optical cable is between 100 N and 200 N.

[0089] The present invention solves the defects existing in the background technology. The present invention has the following beneficial effects: There is a rib 5 on the outer side of the outer sheath 3, which reduces the friction force when the optical cable is laid in the outer pipeline, ensuring the completion of the laying of the air-blown optical cable; at the same time, it controls the driving force F f pushing the optical cable to move is greater than 50 N per meter, which can complete the laying of the optical cable more quickly and efficiently, saving time and effort. When the driving force of the optical cable is greater than 50 N per meter, to ensure production, the pitch of the spiral rib 5 is set to be less than or equal to 0.5 m, ensuring the laying efficiency of the optical cable.

[0090] Based on the inspiration of the ideal embodiments of the present invention, through the above description, relevant personnel can completely make various changes and modifications without departing from the technical idea of this invention. The technical scope of this invention is not limited to the content in the specification, and the technical scope must be determined according to the scope of the claims.

[0091] The preferred embodiments of the present invention have been described in detail above in conjunction with the accompanying drawings. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0092] In addition, it should be noted that, among the various specific technical features described in the above specific embodiments, without conflict, they can be combined in any suitable way. To avoid unnecessary repetition, the present invention will not separately describe various possible combination methods.

[0093] Furthermore, any combination can be made among various different embodiments of the present invention, as long as it does not violate the idea of the present invention, and it should also be regarded as the content disclosed by the present invention.

Claims

1. An air-blown optical cable, characterized in that: It includes an optical cable core (1) and an outer sheath (3) covering the outside of the cable core (1). A rib (5) is provided on the outer wall of the outer sheath (3). The height direction of the rib (5) extends radially outward along the radial direction of the optical cable, and the length direction of the rib (5) extends along the axial direction of the blown optical cable and spirally surrounds the outer surface of the outer sheath (3). The gas advances along the spiral direction of the rib (5), generating a thrust component on the optical cable in the axial direction, and the thrust component pushes the driving force F for the movement of the optical cable per meter f is greater than 50 N, and the driving force F f is calculated by the formula: ； Wherein: ； ； ； F f During the air-blowing process, the radial driving force exerted on the optical cable; S is the total length after the starting point of the rib (5) is unfolded along the circumference of the optical cable; is the composite 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 helical rib (5) and the axial direction of the optical cable; P P is the internal pressure in the pipe under a given air-blowing device and pipeline; h is the height of the rib (5).

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

3. The blown optical cable according to claim 2, wherein: The pitch of the helical rib (5) is set to be 0.01 - 0.5 m.

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

5. The blown optical cable according to claim 1, characterized in that: A strengthening member (4) is arranged in the outer sheath (3), and the strengthening member (4) is circumferentially and uniformly arranged in the outer sheath (3).

6. The blown optical cable according to claim 5, wherein: The strengthening member (4) is set as an aramid fiber rod or a glass fiber rod.

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

8. The blown optical cable according to claim 1, wherein: The cable core (1) includes a plurality of optical fibers (11) and an adhesive part (12) that adhesively bonds the plurality of optical fibers (11) intermittently in the axial direction. Two color wires (14) are arranged outside the plurality of optical fibers (11), and the two color wires (14) are wound in a positive and negative manner to bundle the plurality of optical fibers (11) into a bundle.

9. The blown optical cable according to claim 8, wherein: Any adhesive part on any optical fiber is the first reference adhesive part, the adjacent adhesive part on the optical fiber adjacent to the first reference adhesive part is the second reference adhesive part, and the adjacent adhesive part on the optical fiber adjacent to the second reference adhesive part is the third reference adhesive part. The first reference adhesive part, the second reference adhesive part, and the third reference adhesive part are on the same straight line.

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

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