Composite ribbon optical cable

Abstract

The present invention relates to the technical field of ribbon optical cables, and in particular to a composite ribbon optical cable. It comprises an inner tube body for accommodating a cable core, an outer tube body for supporting an optical cable layer, a heat dissipation unit arranged between the inner tube body and the outer tube body, and a water-blocking layer and an outer protective layer sequentially arranged on the outside of the optical cable layer; the optical cable layer comprises a plurality of optical fiber ribbons, which are arranged in a close fit on the outside of the outer tube body and extend along the length direction of the composite ribbon optical cable; the heat dissipation unit comprises a plurality of heat dissipation bodies arranged radially from the center, the heat dissipation body comprises a first heat dissipation fin, a second heat dissipation fin, and a thermally conductive silica gel attached to the first heat dissipation fin and the second heat dissipation fin, one end of the first heat dissipation fin is fixed to the inner tube body, one end of the second heat dissipation fin is fixed to the outer tube body, and the heat dissipation body divides the heat dissipation unit into a plurality of heat dissipation channels; a first heat dissipation hole connected to the heat dissipation channel is arranged in the gap area between two adjacent optical fiber ribbons. The present invention can improve the heat dissipation effect and ensure the stable operation of the optical cable under high load conditions.

Description

Technical Field

[0001] The present invention relates to the technical field of ribbon optical cables, and in particular to a composite ribbon optical cable. Background Art

[0002] With the increasing complexity of current optical fiber application scenarios, ribbon cables are compact and neatly arranged, which can better adapt to complex paths in wiring. They are widely used in large-core optical fiber rings in metropolitan area networks, access network trunk cables, and other environments, playing an important role in realizing optical fiber to residential areas (or roadsides, buildings, and units).

[0003] In order to further expand the application scenarios of ribbon optical cables, especially in situations where communication and power need to be transmitted at the same time, optoelectronic composite ribbon optical cables are gradually being developed and applied. This type of optical cable integrates optical fiber and metal conductors in one system, realizing the synchronous transmission of optical signals and power, and is widely used in scenarios such as smart grids and smart cities that require synchronous transmission of power and data.

[0004] However, due to the introduction of metal conductors in optoelectronic composite ribbon cables, new problems also arise. Metal conductors generate a lot of heat during power transmission, and optical fibers are sensitive to temperature, and transmission performance is easily affected by temperature rise. In addition, in optoelectronic composite ribbon cables, the contact surface between the optical fiber ribbon and the metal conductor is inconsistent due to the long strip shape of the optical fiber ribbon. This leads to large differences in heat conduction to the optical fiber ribbon in different areas. This difference will cause heat accumulation in some areas of the optical fiber ribbon, affecting the transmission quality of the optical fiber signal and causing a decrease in the overall transmission stability of the optical cable.

[0005] On this basis, the structure of optoelectronic composite ribbon cable is more complex, with both optical fiber ribbon and metal conductor. Due to its flat structure, the tensile performance and mechanical strength of optical fiber ribbon are relatively poor. Especially when subjected to longitudinal tension or lateral extrusion, the mechanical stress of optical fiber ribbon is concentrated in certain specific areas, which may increase the risk of damage to optical fiber or power line. Especially in complex laying environments, optical fiber is easily damaged by bending or excessive stretching.

[0006] The information disclosed in this background technology section is only intended to deepen the understanding of the overall background technology of the present invention, and should not be regarded as acknowledging or suggesting in any form that the information constitutes the prior art known to those skilled in the art. Summary of the invention

[0007] The technical problem to be solved by the present invention is to provide a composite ribbon optical cable, which solves the uneven influence of heat generated by metal conductors on optical fiber ribbons by optimizing the design of heat dissipation units and improving the structural layout, and improves the heat dissipation performance and mechanical strength of the optical cable, thereby solving the problems existing in the existing optoelectronic composite ribbon optical cables in terms of heat dissipation, uneven heat conduction, mechanical stress, etc.

[0008] In order to achieve the above object, the technical solution adopted by the present invention is:

[0009] A composite ribbon optical cable comprises an inner tube body for accommodating a cable core, an outer tube body for supporting an optical cable layer, a heat dissipation unit arranged between the inner tube body and the outer tube body, and a water blocking layer and an outer protective layer arranged in sequence outside the optical cable layer;

[0010] The optical cable layer includes a plurality of optical fiber ribbons, which are arranged on the outside of the outer tube body and extend along the length direction of the composite ribbon optical cable;

[0011] The heat dissipation unit includes a plurality of heat dissipation bodies arranged radially from the center, the heat dissipation bodies include a first heat dissipation fin, a second heat dissipation fin, and thermally conductive silicone glued to the first heat dissipation fin and the second heat dissipation fin, one end of the first heat dissipation fin is fixed to the inner tube body, one end of the second heat dissipation fin is fixed to the outer tube body, and the heat dissipation body divides the heat dissipation unit into a plurality of heat dissipation channels; a first heat dissipation hole connected to the heat dissipation channel is provided in the gap area between two adjacent optical fiber ribbons.

[0012] Furthermore, the inner side of the outer tube body is coated with a heat insulating material, and the thermal conductive silicone is non-continuously pasted between the first heat sink and the second heat sink.

[0013] Furthermore, the first heat sink and the second heat sink are both arc-shaped structures, and the distance between two ends of the arc-shaped structures is smaller than the distance between the inner tube body and the outer tube body.

[0014] Furthermore, a plurality of second heat dissipation holes are arranged on the inner tube body, and the second heat dissipation holes are arranged between two adjacent heat dissipation bodies.

[0015] Furthermore, the outer tube body is provided with multiple groups of heat dissipation grooves consisting of a first baffle and a second baffle, the first baffle and the second baffle are arranged in parallel, the first heat dissipation hole is arranged between the first baffle and the second baffle, and the optical fiber ribbon is arranged between the second baffle and the first baffle of two adjacent groups of heat dissipation grooves.

[0016] Furthermore, a plurality of groups of heat dissipation grooves are arranged on the outer tube body along the axial direction of the outer tube body, so that a plurality of optical fiber ribbons are arranged in parallel on the outer tube body.

[0017] Furthermore, the width of the optical fiber ribbon matches the distance between two adjacent groups of heat dissipation slots, the thickness of the optical fiber ribbon is smaller than the height of the baffle, and the optical fiber ribbon is formed by curing a plurality of optical fibers through resin.

[0018] Furthermore, the cable core is arranged at the center of the composite ribbon optical cable, including a central conductor, a fire-resistant layer and an insulating layer arranged in sequence from the inside to the outside, and the outer diameter of the insulating layer matches the inner diameter of the inner tube body.

[0019] Furthermore, the water-blocking layer includes a water-blocking tape arranged on the outside of the optical cable layer, the thickness of the water-blocking tape is 0.2 mm, and the overlap rate is 20%.

[0020] Furthermore, the outer protective layer includes a spiral armor layer arranged on the surface of the water-blocking layer, and a highly flame-retardant, low-smoke, halogen-free outer sheath layer extruded on the outer surface of the spiral armor layer.

[0021] The beneficial effects of the present invention are:

[0022] (1) The present invention ensures uniform heat conduction by arranging a heat sink between the inner tube body and the outer tube body, and using thermally conductive silicone to connect the first heat sink and the second heat sink, thereby avoiding heat concentration in certain areas and causing local overheating. The thermal conductivity of the heat dissipation unit is effectively enhanced. The first heat sink and the second heat sink are respectively connected to the inner tube body and the outer tube body to construct multiple heat dissipation channels. The thermally conductive silicone is discontinuous between the first heat sink and the second heat sink to form a third heat dissipation hole, which ensures the circulation of heat and further improves the air convection heat dissipation effect. On this basis, the first heat dissipation hole is arranged in the gap area of ​​the optical fiber ribbon to avoid affecting the optical fiber ribbon, prevent local overheating, and ensure stable operation of the composite ribbon cable under high load conditions.

[0023] (2) The connection between the heat sink and the inner and outer tubes in the present invention forms a solid support structure, which not only ensures the overall stability of the optical cable, but also provides additional resistance to mechanical stress, making the optical cable less susceptible to damage when subjected to mechanical external forces such as tension and bending. The first heat sink and the second heat sink are flexibly connected at several points through thermally conductive silicone, allowing a slight relative sliding between the inner and outer arc-shaped heat sinks when the optical cable is bent, thereby dispersing the bending stress and reducing the tensile or compressive force directly acting on the outer tube. In other words, a "buffer zone" is set between the optical fiber ribbon and the external mechanical stress, reducing the stress concentration on the optical fiber ribbon and protecting it from damage caused by excessive bending and deformation. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1Schematic diagram of the cross-sectional structure of a composite ribbon optical cable according to an embodiment of the present invention;

[0026] Figure 2 Schematic diagram of the structure of a composite ribbon optical cable in an embodiment of the present invention;

[0027] Figure 3 This is a schematic diagram of the installation of the optical cable layer in an embodiment of the present invention;

[0028] Figure 4 A schematic diagram of the structure of an optical fiber ribbon in an embodiment of the present invention;

[0029] Figure 5 A schematic diagram of the structure of a heat dissipation unit in an embodiment of the present invention;

[0030] Figure 6 for Figure 5 A partial enlarged view of the middle A;

[0031] Figure numerals: 10, cable core; 11, central conductor; 12, fire-resistant layer; 13, insulating layer; 20, inner tube body; 21, second heat dissipation hole; 30, heat dissipation unit; 31, heat dissipation body; 32, first heat dissipation fin; 33, second heat dissipation fin; 34, thermal conductive silicone; 35, heat dissipation channel; 36, first heat dissipation hole; 40, outer tube body; 41, first baffle; 42, second baffle; 43, heat dissipation groove; 44, accommodating groove; 50, optical cable layer; 51, optical fiber ribbon; 52, optical fiber; 60, water-blocking layer; 70, outer protective layer; 71, spiral armor layer; 72, outer sheath layer. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0033] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0035] like Figure 1 to Figure 6 A composite ribbon optical cable is shown, comprising an inner tube body 20 for accommodating a cable core 10, an outer tube body 40 for supporting an optical cable layer 50, a heat dissipation unit 30 disposed between the inner tube body 20 and the outer tube body 40, and a water blocking layer 60 and an outer protective layer 70 sequentially disposed outside the optical cable layer 50;

[0036] Specific as Figure 2 As shown, the heat dissipation unit 30 includes a plurality of heat dissipation bodies 31 arranged radially from the center, the heat dissipation body 31 includes a first heat dissipation fin 32, a second heat dissipation fin 33, and a heat conductive silicone 34 pasted with the first heat dissipation fin 32 and the second heat dissipation fin 33, one end of the first heat dissipation fin 32 is fixed to the inner tube body 20, one end of the second heat dissipation fin 33 is fixed to the outer tube body 40, and the heat dissipation body 31 divides the heat dissipation unit 30 into a plurality of heat dissipation channels 35; the gap area between two adjacent optical fiber ribbons 51 is provided with a first heat dissipation hole 36 connected to the heat dissipation channel 35. The heat conductive silicone 34 is discontinuous between the first heat dissipation fin 32 and the second heat dissipation fin 33, forming a third heat dissipation hole to ensure the circulation of heat and further enhance the air convection heat dissipation effect. The plurality of heat dissipation channels 35 can not only quickly extract the heat of the cable conductor, but also evenly distribute the heat flow, prevent local overheating, and improve the stability and service life of the outer optical cable layer 50.

[0037] like Figure 3 As shown, the optical cable layer 50 includes a plurality of optical fiber ribbons 51, which are arranged on the outer side of the outer tube body 40 and extend along the length direction of the composite ribbon optical cable; the inner side of the outer tube body 40 is coated with a heat insulating material, and the heat conductive silica gel 34 is non-continuously pasted between the first heat sink 32 and the second heat sink 33. The inner tube body 20 is also provided with a plurality of second heat dissipation holes 21, which are arranged between two adjacent heat sinks 31. The plurality of first heat dissipation holes 36 extend in sequence along the length direction of the outer tube body 40 in the gap area between the optical fiber ribbons 51, and can form a plurality of air circulation channels on the cross section of the composite ribbon optical cable, further enhancing the convection heat dissipation effect of the air in the heat dissipation channel 35, ensuring that the heat can be evenly dissipated from various areas inside the optical cable through the plurality of heat dissipation holes, and avoiding the accumulation of heat in a certain part. The diameter of the first heat dissipation hole 36 is less than the width of the gap area, ensuring that the heat can flow smoothly through these heat dissipation holes, while not affecting the arrangement and support between the optical fiber ribbons 51.

[0038] like Figure 5As shown, the connection between the heat sink 31 and the inner tube body 20 and the outer tube body 40 in the present invention forms a solid support structure, which not only ensures the overall stability of the optical cable, but also provides additional resistance to mechanical stress, so that the optical cable is not easily damaged when subjected to mechanical external forces such as tension and bending. The first heat sink 32 and the second heat sink 33 are contacted at several points by the thermal conductive silicone 34 to maintain a flexible connection, allowing a slight relative sliding between the first heat sink 32 and the second heat sink 33 when the optical cable is bent, thereby dispersing the bending stress and reducing the tensile or compressive force directly acting on the outer tube body 40. That is, a "buffer zone" is set between the optical fiber ribbon 51 and the external mechanical stress, reducing the stress concentration on the optical fiber ribbon 51 and protecting it from damage caused by excessive bending and deformation. In addition, the heat dissipation channel 35 can still maintain good air circulation when the optical cable is bent, which can prevent the heat sink and the outer tube body 40 from accumulating heat during the bending process, thereby avoiding the temperature increase from affecting the performance of the external optical fiber ribbon 51.

[0039] Specifically, the first heat sink 32 and the second heat sink 33 are both arc-shaped structures, and the distance between the two ends of the arc-shaped structure is smaller than the distance between the inner tube body 20 and the outer tube body 40. That is, the free end of the heat sink 31 does not contact the outer tube body 40, and the free end of the second heat sink 31 does not contact the inner tube body 20. Compared with flat heat sinks, arc-shaped heat sinks can provide a larger surface area, thereby improving the efficiency of heat conduction and dissipation. The arc-shaped structure makes the heat dissipation more uniform, avoids heat accumulation in a certain area, and helps to achieve more efficient heat dissipation. When the composite ribbon optical cable is bent, the side of the arc-shaped heat sink is subjected to the bending force. A single arc-shaped heat sink will not actually directly relieve stress. The present invention can achieve uniform distribution of stress through the heat dissipation channel 35 between the inner and outer tube bodies 40 and the double-layer heat sink structure. During the bending process, the outer tube body 40 itself will be subjected to a certain bending stress. The heat sink in the interlayer disperses the stress to each heat sink during bending through the symmetry of the structure and the internal and external fixed connection method. In addition, combined with the sliding point of the thermal conductive silicone 34 in the middle, it can further reduce the stress concentration in a single direction and prevent local stress from being concentrated in a small area of ​​the outer tube body 40, thereby protecting the optical fiber ribbon 51 on the outside of the outer tube body 40, so that it can still maintain a relatively stable state during bending, reducing breakage or damage caused by excessive stress.

[0040] In order to ensure a stable connection with the thermally conductive silicone 34, grooves are provided on the surfaces of the first heat sink 32 and the second heat sink 33, which not only increases the contact area between the thermally conductive silicone 34 and the first heat sink 32 and the second heat sink 33, but also improves the bonding effect of the thermally conductive silicone 34, prevents the thermally conductive silicone 34 from sliding or falling off during the curing process, and ensures efficient heat conduction between the first heat sink 32 and the second heat sink 33 and the silicone.

[0041] Specifically, the outer tube body 40 is also provided with multiple groups of heat dissipation grooves 43 consisting of a first baffle 41 and a second baffle 42. The first baffle 41 and the second baffle 42 are arranged in parallel, the first heat dissipation hole 36 is arranged between the first baffle 41 and the second baffle 42, and the optical fiber ribbon 51 is arranged between the second baffle 42 and the first baffle 41 of two adjacent groups of heat dissipation grooves 43.

[0042] Please continue to refer to Figure 3 , the width of the optical fiber ribbon 51 matches the distance between two adjacent groups of heat dissipation grooves 43, ensuring that the optical fiber ribbon 51 can be firmly fixed between the baffles, avoiding displacement or distortion of the optical fiber ribbon 51 due to external force during laying or use, ensuring the neat arrangement of the optical fiber ribbon 51, and facilitating the long-term stability of the transmission performance of the optical fiber 52. On this basis, the height of the baffle is greater than the thickness of the optical fiber ribbon 51, which can provide sufficient buffer protection for the optical fiber ribbon 51 and prevent the optical fiber ribbon 51 from directly bearing external force. When the optical cable is bent or stretched, the baffle can effectively share part of the force, reduce the stress concentration of the optical fiber ribbon 51 itself, and improve the bending and stretching resistance of the optical cable. The optical fiber ribbon 51 is formed by curing multiple optical fibers 52 with resin, and the outer side of the multiple optical fibers 52 is also coated with a sheath layer. The cooperation of the first baffle 41, the second baffle 42 and the water-blocking tape forms a relatively tight and closed structure, which effectively improves the mechanical impact resistance of the optical cable.

[0043] like Figure 5 In the present invention, a plurality of groups of heat dissipation grooves 43 are arranged on the outer tube body 40 along the axial direction of the outer tube body 40, so that a plurality of optical fiber ribbons 51 are arranged in parallel on the outer tube body 40. The structure of the optical fiber ribbons 51 arranged in parallel is relatively simple, and no complex control is required during the manufacturing process, the production speed is fast, and the cost is relatively low. In the present invention, a receiving groove 44 for accommodating the optical fiber ribbon 51 is formed between the second baffle 42 and the first baffle 41 of two adjacent groups of heat dissipation grooves 43. After the optical fiber ribbons 51 are arranged, they are fixed by a water-blocking tape to ensure that the position of the optical fiber ribbon 51 in the composite ribbon optical cable is stable, and the movement or bending of the optical fiber ribbon 51 when subjected to external forces during installation or use is reduced. At this time, in each heat dissipation channel 35, multiple first heat dissipation holes 36 are arranged along the axis of the outer tube body 40. In addition to the circulation along the arc-shaped structure of the heat sink inside the heat dissipation channel 35, the heat will be gathered to the area where the first heat dissipation holes 36 are located and flow out. The axial arrangement design ensures that the heat flows relatively evenly in the entire channel. The internal and external circulation modes of the first heat dissipation holes 36 and the second heat dissipation holes 21 ensure efficient heat dissipation inside the composite ribbon optical cable and avoid heat accumulation, thereby improving the stability and reliability of the composite ribbon optical cable under long-term working conditions.

[0044] Please continue to refer to Figure 2The cable core 10 is arranged at the center of the composite ribbon optical cable, including a central conductor 11, a fire-resistant layer 12 and an insulating layer 13 arranged in sequence from the inside to the outside, realizing a high-safety design of the cable core 10, wherein the outer diameter of the insulating layer 13 matches the inner diameter of the inner tube body 20, the central conductor 11 is responsible for transmitting current, and the close fit between the insulating layer 13 and the inner tube body 20 reduces the electromagnetic loss inside the cable core 10, improves the current transmission efficiency, ensures that the electrical performance will not be affected under the working load, and guarantees the signal transmission quality in harsh environments.

[0045] In the present invention, the water-blocking layer 60 includes a water-blocking tape arranged on the outside of the optical cable layer 50, the thickness of the water-blocking tape is 0.2 mm, and the overlap rate is 20%. An effective water-blocking barrier is formed to prevent moisture from penetrating into the optical fiber 52 layer, thereby ensuring the long-term stability of the optical fiber 52 in a humid environment. The outer protective layer 70 includes a spiral armor layer 71 arranged on the surface of the water-blocking layer 60, and a highly flame-retardant, low-smoke, halogen-free outer sheath layer 72 extruded on the outer surface of the spiral armor layer 71. The spiral armor layer 71 provides additional mechanical protection to prevent damage by external forces, and the outer sheath layer 72 is made of highly flame-retardant, low-smoke, halogen-free materials, which not only meets the fire resistance requirements, but also produces less smoke and harmful gases when the optical cable is directly attacked by flames, thereby improving safety and meeting the strict requirements of environmental protection and building fire protection.

[0046] Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A composite ribbon optical cable, characterized in that: It includes an inner tube body for accommodating a cable core, an outer tube body for supporting an optical cable layer, a heat dissipation unit arranged between the inner tube body and the outer tube body, and a water blocking layer and an outer protective layer arranged in sequence outside the optical cable layer; The optical cable layer includes a plurality of optical fiber ribbons, which are arranged on the outside of the outer tube body and extend along the length direction of the composite ribbon optical cable; The heat dissipation unit includes a plurality of heat dissipation bodies arranged radially from the center, the heat dissipation body includes a first heat dissipation fin, a second heat dissipation fin, and thermally conductive silicone glued to the first heat dissipation fin and the second heat dissipation fin, one end of the first heat dissipation fin is fixed to the inner tube body, one end of the second heat dissipation fin is fixed to the outer tube body, and the heat dissipation body divides the heat dissipation unit into a plurality of heat dissipation channels; a first heat dissipation hole connected to the heat dissipation channel is provided in a gap area between two adjacent optical fiber ribbons.

2. A composite ribbon optical cable according to claim 1, characterized in that: The inner side of the outer tube is coated with a heat insulating material, and the heat conductive silica gel is non-continuously pasted between the first heat sink and the second heat sink.

3. A composite ribbon optical cable according to claim 2, characterized in that: The first heat sink and the second heat sink are both arc-shaped structures, and the distance between two ends of the arc-shaped structure is smaller than the distance between the inner tube body and the outer tube body.

4. A composite ribbon optical cable according to claim 3, characterized in that: The inner tube body is also provided with a plurality of second heat dissipation holes, and the second heat dissipation holes are arranged between two adjacent heat dissipation bodies.

5. A composite ribbon optical cable according to claim 1, characterized in that: The outer tube body is also provided with a plurality of groups of heat dissipation grooves consisting of a first baffle and a second baffle, the first baffle and the second baffle are arranged in parallel, the first heat dissipation hole is arranged between the first baffle and the second baffle, and the optical fiber ribbon is arranged between the second baffle and the first baffle of two adjacent groups of heat dissipation grooves.

6. A composite ribbon optical cable according to claim 5, characterized in that: A plurality of groups of heat dissipation grooves are arranged on the outer tube body along the axial direction of the outer tube body, so that a plurality of optical fiber ribbons are arranged in parallel on the outer tube body.

7. A composite ribbon optical cable according to claim 6, characterized in that: The width of the optical fiber ribbon matches the distance between two adjacent groups of the heat dissipation slots, the thickness of the optical fiber ribbon is smaller than the height of the baffle, and the optical fiber ribbon is formed by curing a plurality of optical fibers through resin.

8. A composite ribbon optical cable according to any one of claims 1 to 7, characterized in that: The cable core is arranged at the center of the composite ribbon optical cable, and comprises a central conductor, a fire-resistant layer and an insulating layer which are arranged in sequence from the inside to the outside, and the outer diameter of the insulating layer matches the inner diameter of the inner tube body.

9. A composite ribbon optical cable according to any one of claims 1 to 7, characterized in that: The water-blocking layer comprises a water-blocking tape arranged outside the optical cable layer, the thickness of the water-blocking tape is 0.2 mm, and the overlap rate is 20%.

10. A composite ribbon optical cable according to any one of claims 1 to 7, characterized in that: The outer protective layer comprises a spiral armor layer arranged on the surface of the water-blocking layer, and a highly flame-retardant, low-smoke, halogen-free outer sheath layer extruded on the outer surface of the spiral armor layer.

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