A composite layer-twisted optical cable

Abstract

The present invention relates to the field of optical cable technology, and in particular to a composite layer-stranded optical cable, comprising a reinforcing core arranged in the center, a plurality of optical fiber bundle tubes twisted around the reinforcing core, and a foam buffer layer, a first water-blocking layer, a cladding layer and a sheath layer sequentially arranged on the outer layers of the plurality of optical fiber bundle tubes; a second water-blocking layer is filled in the gaps between the foam buffer layer and the optical fiber bundle tube, and between the optical fiber bundle tube and the reinforcing core; the foam buffer layer adopts a closed-cell structure, a plurality of groups of holes are radially arranged, water-blocking materials are arranged in the holes, two ends of the water-blocking materials are respectively connected to the first water-blocking layer and the second water-blocking layer, the overall mechanical strength of the foam buffer layer is increased by the water-blocking material arranged in the holes of the foam buffer layer, and the water-blocking structure as a whole is tightly combined with the foam buffer layer by being connected to the first water-blocking layer and the second water-blocking layer, and this tight combination effectively prevents the separation and displacement of each level under external stress, and maintains the integrity and stability of the structure.

Description

Technical Field

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

[0002] Composite twisted optical cables are widely used in urban communication networks, long-distance communication systems, power system communication networks and other communication networks that require high performance and high reliability. These characteristics make composite twisted optical cables occupy an important position in the construction of modern communication infrastructure.

[0003] Composite stranded optical cables usually consist of the following parts:

[0004] Central strength member: Located in the center of the optical cable, usually steel wire or fiber-reinforced plastic material, used to provide mechanical strength and tensile resistance to the optical cable.

[0005] Fiber bundle tube: includes optical fiber and loose tube installed on the outside. The loose tube is usually made of polybutylene terephthalate material to protect the optical fiber from the influence of the external environment.

[0006] Filling grease: Filled in the loose tube to prevent water and moisture, ensuring the stability of the optical fiber under various environmental conditions.

[0007] Coating: Several layers can be set to protect the twisted optical fiber bundle tube, which often also includes an elastic layer for buffering.

[0008] Water-blocking material: usually set between different coating layers, or coated on the outside of the twisted optical cable bundle tube, generally using water-swelling yarn, water-swelling tape, etc. to prevent moisture from penetrating into the optical cable.

[0009] Sheath layer: Located on the outermost layer of the optical cable, the sheath material is mostly polyethylene or low-smoke halogen-free material, which is used to protect the optical cable from mechanical damage and chemical corrosion from the external environment.

[0010] In the above structure, each layer wrapped on the outside of the structure after the optical fiber bundle tube is twisted is independent of each other, and the functions implemented by each layer are also independent of each other; with the continuous optimization and improvement of the product, the difficulty of optimizing the overall product through independent improvements at each layer is increased.

[0011] 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 already known to those skilled in the art. Summary of the invention

[0012] The present invention provides a composite layer-twisted optical cable, thereby effectively solving the problems pointed out in the background technology.

[0013] In order to achieve the above object, the technical solution adopted by the present invention is:

[0014] A composite layer-stranded optical cable, comprising a reinforcing core arranged in the center, a plurality of optical fiber bundle tubes twisted around the reinforcing core, and a foam buffer layer, a first water-blocking layer, a cladding layer and a sheath layer sequentially arranged on the outer layers of the plurality of optical fiber bundle tubes;

[0015] The gaps between the foam buffer layer and the optical fiber bundle tube, and between the optical fiber bundle tube and the reinforcing core are filled with a second water-blocking layer;

[0016] The foam buffer layer adopts a closed-cell structure and is radially provided with a plurality of groups of holes. Water-blocking materials are arranged in the holes, and two ends of the water-blocking material are respectively connected to the first water-blocking layer and the second water-blocking layer.

[0017] Furthermore, the second water-blocking layer is obtained by injecting the water-blocking material into the hole and solidifying it in the gap between the foam buffer layer and the optical fiber bundle tube, and between the optical fiber bundle tube and the reinforcing core.

[0018] Furthermore, after the water-blocking material is injected into the second water-blocking layer through the holes at the set positions, the water-blocking material is controlled to overflow from the holes at the remaining positions, and the overflowed part participates in the forming of the first water-blocking layer.

[0019] Furthermore, the first water-blocking layer is formed by a mold arranged outside the foam buffer layer, and the water-blocking material overflowing from the hole part and the water-blocking material in the mold are solidified to form the first water-blocking layer together.

[0020] Furthermore, the water-blocking material of the first water-blocking layer and the second water-blocking layer is epoxy resin or polyolefin copolymer.

[0021] Furthermore, the plurality of groups of holes are arranged at equal intervals along the length direction of the foam buffer layer.

[0022] Furthermore, each group of holes includes at least two holes, and the holes are evenly distributed around the axis of the composite stranded optical cable.

[0023] Furthermore, at least part of the hole is provided with a tapered section, and the tapered section gradually expands the hole close to the first water-blocking layer.

[0024] Furthermore, the hole penetrates the foam buffer layer through a heating body, and the heating body causes the foam buffer layer to partially melt, and is formed after being pulled out.

[0025] Furthermore, the thickness of the foam buffer layer is greater than the thickness of the first water-blocking layer.

[0026] Through the technical solution of the present invention, the following technical effects can be achieved: the overall mechanical strength of the foam buffer layer is increased by the water-blocking material arranged in the holes of the foam buffer layer, and the water-blocking structure as a whole is tightly combined with the foam buffer layer through the connection with the first water-blocking layer and the second water-blocking layer. This tight combination effectively prevents the separation and displacement of each layer under external stress, thereby maintaining the integrity and stability of the structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] 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.

[0028] Figure 1 It is a cross-sectional view of a composite stranded optical cable;

[0029] Figure 2 A schematic diagram of the structure of processing a foam buffer layer on the outer layer of multiple optical fiber bundle tubes;

[0030] Figure 3 A schematic diagram of the structure for processing multiple groups of holes on a foam buffer layer;

[0031] Figure 4 A schematic diagram of the structure in which the injection nozzle is inserted into each group of holes and the water-blocking material is injected synchronously from multiple directions;

[0032] Figure 5 It is a schematic diagram of the structure of processing the first water-blocking layer on the foam buffer layer;

[0033] Figure 6 It is a structural schematic diagram of the tapered section.

[0034] Reference numerals: 1, reinforcing core; 2, optical fiber bundle tube; 3, second water-blocking layer; 4, foam buffer layer; 41, water-blocking material; 42, hole; 421, tapered section; 5, first water-blocking layer;

[0035] 01. Inject into the mouth. DETAILED DESCRIPTION

[0036] 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.

[0037] 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.

[0038] like Figures 1 to 6 As shown: a composite layer-stranded optical cable, comprising a reinforcing core 1 arranged in the center, a plurality of optical fiber bundle tubes 2 twisted around the reinforcing core 1, and a foam buffer layer 4, a first water-blocking layer 5, a cladding layer and a sheath layer (not shown in the figure) sequentially arranged on the outer layers of the plurality of optical fiber bundle tubes 2;

[0039] The gaps between the foam buffer layer 4 and the optical fiber bundle tube 2, and between the optical fiber bundle tube 2 and the reinforcing core 1 are filled with a second water-blocking layer 3;

[0040] The foam buffer layer 4 adopts a closed-cell structure and is provided with a plurality of groups of holes 42 in the radial direction. Water-blocking material 41 is provided in the holes 42 . Both ends of the water-blocking material 41 are connected to the first water-blocking layer 5 and the second water-blocking layer 3 respectively.

[0041] The foam buffer layer 4 can be a polyethylene foam with a closed-cell structure, which can ensure that the water-blocking material 41 cannot be accommodated at other positions except the hole 42, thereby ensuring the ultimate buffering effect; after the optical fiber bundle tube 2 is twisted around the central reinforcing core 1 to obtain a twisted structure, it is molded on the outside of the twisted structure and a gap is formed between the twisted structure. The closed-cell structure means that each hole 42 is closed and is not connected to other holes 42. This structure gives it excellent heat insulation and waterproof properties.

[0042] By providing the foam buffer layer 4, the first water-blocking layer 5 and the second water-blocking layer 3, a multi-layer water-blocking barrier is provided. The multi-layer protection can effectively prevent moisture penetration and ensure that the optical cable remains dry in a humid environment. Through the combination of the inner and outer water-blocking layers, comprehensive protection is provided to ensure that even under extreme conditions, moisture is difficult to penetrate into the interior of the optical cable, thereby protecting the optical fiber and other key components.

[0043] In the present invention, the water-blocking material 41 arranged in the holes 42 of the foam buffer layer 4 increases the overall mechanical strength of the foam buffer layer 4. By connecting with the first water-blocking layer 5 and the second water-blocking layer 3, the water-blocking structure as a whole is tightly combined with the foam buffer layer 4. This tight combination effectively prevents the separation and displacement of each layer under external stress, and maintains the integrity and stability of the structure.

[0044] The water-blocking structure provides a multi-level waterproof barrier, ensuring that water penetration is effectively prevented in multiple ways, significantly improving the waterproof performance; the excellent shock absorption effect of the foam buffer layer 4 combined with the mechanical strength of the water-blocking material 41 enhances the overall mechanical protection and structural stability of the optical cable, and effectively prevents layer separation under external forces; the chemical corrosion resistance and weather resistance of the optical cable are enhanced, so that the optical cable can still maintain stable performance in various harsh environments.

[0045] As a preferred embodiment of the above embodiment, the second water-blocking layer 3 is obtained by injecting a water-blocking material 41 into the hole 42 and curing it in the gaps between the foam buffer layer 4 and the optical fiber bundle tube 2, and between the optical fiber bundle tube 2 and the reinforcing core 1. The water-blocking material 41 is uniformly cured in each gap, ensuring that each gap is completely sealed, preventing the invasion of water and moisture, and improving the reliability of the optical cable in a humid or underwater environment; in addition, the cured water-blocking material 41 not only provides a waterproof function, but also plays a reinforcing role, thereby enhancing the mechanical connection between the foam buffer layer 4, the optical fiber bundle tube 2 and the reinforcing core 1, and preventing layer separation and structural damage under the action of external forces. In addition, the production process of injecting the water-blocking material 41 simplifies the manufacturing process, is suitable for large-scale production and provides customized solutions.

[0046] In this embodiment, after the water-blocking material 41 is injected into the position of the second water-blocking layer 3 through the holes 42 at the set positions, the water-blocking material 41 is controlled to overflow from the holes 42 at the remaining positions, and the overflowed part participates in the molding of the first water-blocking layer 5. The overflow process ensures that the residual air is discharged, prevents the formation of bubbles, and ensures that there are no bubbles inside the second water-blocking layer 3 after injection, thereby forming a uniform and continuous water-blocking layer, thereby ensuring that the second water-blocking layer 3 is completely filled; the water-blocking material 41 needs to form a seamless barrier to exert its optimal performance. The overflow process ensures that the entire space inside the foam filling layer is occupied by the water-blocking material 41, so that the water-blocking layer has the best mechanical strength and waterproof performance. In this preferred embodiment, the water-blocking material 41 overflows so that the water-blocking material 41 in the hole 42 can be integrally connected to the first water-blocking layer 5 and the second water-blocking layer 3 after solidification. This integrated molding method further prevents the separation and displacement of the layers under external stress. The mixing of the overflowing material and the remaining molding material of the first water-blocking layer 5 outside the foam buffer layer 4 is easy to control, and the molding effect of the first water-blocking layer 5 is finally controllable. In the implementation process, it is preferred that each group of holes 42 has material overflow, that is, after the injection structure is removed, the injection position of the material also needs to overflow part of the material during the subsequent material injection process, so as to ensure the integrity of the subsequent water-blocking structure.

[0047] Among them, the first water-blocking layer 5 is formed by a mold arranged on the outside of the foam buffer layer 4, and the water-blocking material 41 overflowing from the hole 42 is solidified with the water-blocking material 41 in the mold to form the first water-blocking layer 5 together. Specifically, the part overflowing from the hole 42 is often insufficient to form an external water-blocking layer due to the limited amount of the overflowing water-blocking material 41. Therefore, additional water-blocking material 41 is required to be added externally. The thickness of the first water-blocking layer 5 is controlled by the mold, so that the molding of the water-blocking layer is more precise, the error in production is reduced, and the consistency and reliability of the product are improved; the first water-blocking layer 5 is also formed outside the foam buffer layer 4, and the second water-blocking layer 3 inside the foam buffer layer 4, the first water-blocking layer 5 outside, and the water-blocking material 41 in the hole 42 together form a multi-layered water-blocking structure, which greatly improves the overall waterproof performance of the optical cable and ensures the reliability of the optical cable in a humid or underwater environment.

[0048] As a preferred embodiment of the above embodiment, the water-blocking material 41 of the first water-blocking layer 5 and the second water-blocking layer 3 is epoxy resin or polyolefin copolymer. Specifically, epoxy resin has strong adhesion and can firmly adhere to the surface of various materials, including metal, plastic and foam. This adhesion ensures the stability and durability of the water-blocking layer; the cured epoxy resin has extremely high mechanical strength and can withstand large tensile, compression and impact forces, providing solid protection; epoxy resin is resistant to a variety of chemicals, including oils, acids, alkalis and solvents, and is suitable for harsh environments; during the curing process, the shrinkage rate of epoxy resin is low, ensuring the dimensional stability of the finished product, so epoxy resin can be used for optical cable water-blocking protection with high mechanical strength and stability; and polyolefin copolymer (POE, Polyolefin Elastomer) is cured by a cross-linking agent (such as peroxide or vulcanizer) to form a material with elasticity and high mechanical strength, which can maintain its shape during stretching and bending and adapt to the dynamic stress of the optical cable; and the polyolefin copolymer material has good weather resistance, can maintain stable performance under various temperature and humidity conditions, and is not easy to age; in addition, it has excellent wear resistance and is suitable for optical cables that are frequently moved or subjected to friction; in addition, polyolefin materials are generally non-toxic and environmentally friendly, and do not produce harmful substances when discarded. Therefore, polyolefin copolymers are suitable for optical cables that require a combination of flexibility and high strength. Epoxy resin or polyolefin copolymer can be selected as the water-blocking material41 according to the use requirements, which can optimize the performance of the optical cable and meet the requirements of different application scenarios.

[0049] The specific curing procedure is as follows: Epoxy resin is usually cured by mixing two components (epoxy resin and curing agent). The specific conditions can be room temperature curing or heating curing. The curing process takes a certain amount of time to achieve the final mechanical strength; while polyolefin copolymers are cross-linked and cured by adding peroxides or vulcanizing agents, usually at higher temperatures, so that the material forms a network structure and enhances its mechanical properties and elasticity.

[0050] In this embodiment, multiple groups of holes 42 are arranged at equal intervals along the length direction of the foam buffer layer 4. Specifically, since the optical cable is continuously transmitted and processed layer by layer during the processing, when processing the second water-blocking layer 3, the foam buffer layer 4 first stops, and after the water-blocking material 41 is injected into the gap between the foam buffer layer 4 and the twisted structure according to the set interval to form the second water-blocking layer 3 of the first section, the foam buffer layer 4 continues to move forward for a certain distance and then stops. At this time, the water-blocking material 41 is injected into the second group of holes 42 to form the second water-blocking layer 3 of the second section. By analogy, the second water-blocking layer 3 inside is formed. Multiple holes 42 are arranged at equal intervals along the length direction of the foam buffer layer 4, ensuring that the moving distance and the filling time of the injection nozzle 01 are arranged at equal intervals, which is conducive to automatic control and improves production accuracy. At the same time, it ensures that the injection of the water-blocking material 41 is evenly distributed, forming a reliable waterproof barrier of the second water-blocking layer. In the implementation process, the material injection action can be performed in each group of holes 42, or the injection can be performed at intervals of a set number of holes 42, and the remaining groups of holes 42 can only be used for material overflow.

[0051] Among them, each group of holes 42 includes at least two holes, and each hole is evenly distributed around the axis of the composite layer twisted optical cable. In this embodiment, the number of holes in each group of holes 42 can be six. Of course, this is only a specific number selection. In the actual implementation process, the number of holes in each group of holes 42 can be set according to the needs of the site, which is within the protection scope of this application; when the water-blocking material 41 is injected into the position where the second water-blocking layer 3 is located from the evenly distributed holes 42, on the one hand, the circumferential filling distribution of this section of the second water-blocking layer 3 can be uniformly formed to form a continuous and uniform waterproof barrier, effectively preventing moisture penetration in any direction, and improving the waterproof performance; on the other hand, the uniform distribution design simplifies the control and adjustment in the production process, improves the production accuracy, and the automated equipment can more easily achieve this symmetrical distribution to ensure the consistency and reliability of production.

[0052] As a preferred embodiment of the above embodiment, the hole 42 is at least partially provided with a tapered section 421, and the tapered section 421 gradually expands the hole 42 close to the first water-blocking layer 5. Specifically, on the one hand, the tapered section 421 plays a guiding role, so that the injection nozzle head 01 can be quickly and accurately aligned with the hole 42, reducing the adjustment time and improving the injection efficiency; on the other hand, the tapered section 421 makes the seal between the injection nozzle head 01 and the hole 42 tighter, reducing the risk of overflow of the water-blocking material 41 at the injection position and the entry of air, ensuring a stable injection amount, reducing the generation of bubbles, and ensuring the integrity and continuity of the waterproof layer.

[0053] In this embodiment, the hole 42 is penetrated by the foam buffer layer 4 through the heating body, and the heating body causes the foam buffer layer 4 to partially melt and is formed after being pulled out. Specifically, the process of using the heating body to penetrate the foam buffer layer 4 to form the hole 42 is fast and efficient, suitable for large-scale production, and improves production efficiency; the heating body can accurately control the position and size of the hole 42, ensure the consistency and uniformity of the hole 42, and avoid irregularities and errors that may be caused by mechanical punching; after the heating body melts the foam buffer layer 4 to form the hole 42, the edge of the hole 42 is smooth and free of burrs, reducing the edge irregularities and microcracks that may be caused by mechanical punching, and improving the quality of the hole 42; because the edge of the hole 42 is smooth, the water-blocking material 41 can better fill the hole 42 when injected, avoiding the generation of bubbles and gaps, and improving the waterproof performance.

[0054] As a preferred embodiment of the above embodiment, the thickness of the foam buffer layer 4 is greater than the thickness of the first water-blocking layer 5. Specifically, the larger thickness of the foam buffer layer 4 can provide better mechanical protection, reduce the impact of external impact on the internal structure of the optical cable, and help prevent the optical fiber bundle tube 2 or other key components from being damaged during transportation and installation; the larger thickness of the foam buffer layer 4 provides better thermal isolation and thermal stability, adapts to high or low temperature environments, and ensures that the internal components of the optical cable are not affected by temperature fluctuations. The lightweight characteristics of the foam buffer layer 4 and the combined flexibility further optimize the weight and adaptability of the optical cable, making it easier to transport and install.

[0055] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. 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, which 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 stranded optical cable, characterized in that: It comprises a reinforcing core arranged in the center, a plurality of optical fiber bundle tubes twisted around the reinforcing core, and a foam buffer layer, a first water-blocking layer, a cladding layer and a sheath layer sequentially arranged on the outer layers of the plurality of optical fiber bundle tubes; The gaps between the foam buffer layer and the optical fiber bundle tube, and between the optical fiber bundle tube and the reinforcing core are filled with a second water-blocking layer; The foam buffer layer adopts a closed-cell structure and is radially provided with a plurality of groups of holes, the holes are provided with a water-blocking material, and the two ends of the water-blocking material are respectively connected to the first water-blocking layer and the second water-blocking layer; The second water-blocking layer is obtained by injecting the water-blocking material into the hole and solidifying it in the gap between the foam buffer layer and the optical fiber bundle tube, and between the optical fiber bundle tube and the reinforcing core; The water-blocking material of the first water-blocking layer and the second water-blocking layer is epoxy resin or polyolefin copolymer; After the water-blocking material is injected into the second water-blocking layer through the holes at the set positions, the water-blocking material is controlled to overflow from the holes at the remaining positions, and the overflowed part participates in the forming of the first water-blocking layer.

2. The composite stranded optical cable according to claim 1, characterized in that: The first water-blocking layer is formed by a mold arranged outside the foam buffer layer, and the water-blocking material overflowing from the hole part and the water-blocking material in the mold are solidified to form the first water-blocking layer together.

3. The composite stranded optical cable according to claim 1, characterized in that: The plurality of groups of holes are arranged at equal intervals along the length direction of the foam buffer layer.

4. The composite stranded optical cable according to claim 1, characterized in that: Each group of holes includes at least two holes, and the holes are evenly distributed around the axis of the composite stranded optical cable.

5. The composite stranded optical cable according to claim 1, characterized in that: At least part of the hole is provided with a tapered section, and the tapered section gradually expands the hole near the first water-blocking layer.

6. The composite stranded optical cable according to claim 1, characterized in that: The holes penetrate the foam buffer layer through a heating body, and the heating body causes the foam buffer layer to partially melt, and are formed after being pulled out.

7. The composite stranded optical cable according to claim 1, characterized in that: The thickness of the foam buffer layer is greater than the thickness of the first water-blocking layer.

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