A synaesthetic integrated butterfly-shaped fiber optic cable for lead-in

Abstract

The present invention relates to the technical field of communication optical cables, and in particular to a communication and sensing integrated butterfly lead-in optical cable, comprising: a first strengthening member, an inner skeleton, an optical cable layer, an outer skeleton and an outer protective layer; the optical cable layer includes a plurality of butterfly units connected in series, and the butterfly unit includes a sheath, a communication unit, a second strengthening member and a sensing unit. The sheath includes a main body portion and mounting portions symmetrically arranged on both sides of the main body portion; one end of the mounting portion is fixed to the main body portion, and the free end is bent reversely and extended to form an arc channel, and the diameter of the arc channel is larger than the opening distance between the fixed end and the free end of the mounting portion. The communication unit and the sensing unit are installed in the arc channel. Through the unique design of the butterfly sheath structure, the mutual independence of the optical fiber units and the optimization of the open-shaped mounting portions are realized, effectively reducing signal interference, improving the compressive performance and environmental adaptability of the optical cable, while simplifying the construction and maintenance processes and reducing the maintenance cost.

Description

Technical Field

[0001] The present invention relates to the technical field of communication optical cables, and particularly to a communication and sensing integrated butterfly-shaped drop cable. Background Art

[0002] With the rapid development of information technology, fiber optic communication technology has become the main pillar in the modern communication field due to its significant advantages such as high speed, large capacity, and low loss. As an important transmission medium for fiber optic communication, the butterfly-shaped optical cable has been widely used in scenarios such as fiber to the home (FTTH), intelligent buildings, and data centers due to its unique shape and excellent performance.

[0003] The communication and sensing integrated butterfly-shaped drop cable is a composite optical cable that combines the lightweight wiring characteristics of the butterfly-shaped drop cable and the communication and sensing integrated technology, and is mainly used in the fiber to the home (FTTH) scenario to achieve communication and sensing functions.

[0004] In the prior art, CN209373203U discloses a multi-unit butterfly-shaped drop cable, which includes at least two optical fiber units. The optical fiber units are externally coated with an outer sheath, and the optical fiber units are arranged in parallel along the long axis direction of the outer sheath. A strengthening member is arranged between any two of the optical fiber units. Along the short axis direction of the outer sheath, tear openings are arranged on the outer sheath on both sides of each optical fiber unit, so that each optical fiber unit can be torn separately, which solves to a certain extent the problem of wire sequence confusion caused by stripping all optical fibers during the construction of the butterfly-shaped drop cable.

[0005] However, in the above optical fiber units, the optical fibers are directly coated in the outer sheath. If one optical fiber is damaged, the entire cable needs to be stripped for repair. In the case where the original sealing and protection performance of the outer sheath cannot be restored after re-packaging, it may even be necessary to replace the entire optical cable, which not only increases the complexity of the repair but also significantly raises the cost of fault repair.

[0006] In view of the above problems, based on the rich practical experience and professional knowledge in the engineering application of such products for many years, the inventor of the present invention actively conducts research and innovation in order to create a communication and sensing integrated butterfly-shaped drop cable to make it more practical. Summary of the Invention

[0007] The technical problem to be solved by the present invention is: to provide a communication and sensing integrated butterfly-shaped drop cable to effectively solve the problems in the background art.

[0008] In order to achieve the above object, the technical solution adopted by the present invention is: a communication and sensing integrated butterfly-shaped drop cable, including: a first strengthening member, and an inner skeleton, an optical cable layer, an outer skeleton, and an outer protection layer sequentially arranged outside the first strengthening member from inside to outside;

[0009] The optical cable layer includes a plurality of butterfly units connected in series. Each butterfly unit includes a sheath, a communication unit, a second strengthening member, and a sensing unit arranged in sequence along the long axis direction of the sheath. The sheath includes a main body part for installing the second strengthening member, and mounting parts arranged in central symmetry on both sides of the main body part;

[0010] One end of the mounting part is fixed on the main body part, and the free end is bent reversely to extend to form an arc channel. The diameter of the arc channel is greater than the opening distance between the fixed end and the free end of the mounting part. The communication unit and the sensing unit are installed in the arc channel, and each of them includes a sheath layer, an optical fiber or an optical fiber bundle arranged in the sheath layer, and a strengthening layer outside the sheath layer.

[0011] Further, a plurality of first cavities and a plurality of second cavities are respectively arranged on the toroidal surfaces of the outer skeleton and the inner skeleton facing the optical cable layer. The first cavities and the second cavities are arranged in a staggered manner along the circumferential direction;

[0012] The butterfly unit is embedded in the second cavity at the end of the communication unit and in the first cavity at the end of the sensing unit.

[0013] Further, the openings of the two mounting parts in the first cavity or the second cavity are arranged opposite to each other.

[0014] Further, the outer skeleton includes a split support ring and a plurality of first protrusions arranged on the inner wall between the seams of the two-by-two joints of the support ring;

[0015] The side walls of the two first protrusions forming the first cavity are outwardly convex arc surfaces. The outwardly convex arc surfaces are tangent to the outer edges of the mounting parts embedded in the first cavity, and the free ends abut against the fixed ends of the other mounting parts.

[0016] Further, sealing plates are provided at the free ends of the two outwardly convex arc surfaces, and a closed cavity is formed in the first protrusion.

[0017] Further, the sealing plate is provided with second protrusions facing the second cavity;

[0018] Gaps are left between the two side walls of the second protrusion and the fixed ends of the two mounting parts.

[0019] Further, an auxiliary heat dissipation cavity is arranged in the second protrusion, and the area of the auxiliary heat dissipation cavity is smaller than the area of the closed cavity;

[0020] A heat-conducting silica gel sheet is arranged on the cross-section of the sealing plate between the closed cavity and the auxiliary heat dissipation cavity.

[0021] Further, a third protrusion formed between two adjacent second cavities has an outer ring surface that is concave towards the center of the circle;

[0022] The third protrusion is arranged corresponding to the first cavity, and the outer ring surface is tangent to the outer cylindrical surfaces of two adjacent sheaths.

[0023] Further, the inner skeleton, the outer skeleton, and the sheath are made of one of polyethylene, polyvinyl chloride, polyurethane, or low-smoke and halogen-free flame-retardant polyolefin.

[0024] Further, both the first reinforcing member and the second reinforcing member are made of non-metallic reinforcing members.

[0025] The beneficial effects of the present invention are as follows: In the present invention, the structural design of the butterfly-shaped sheath makes the optical fiber units independent of each other, reduces the mutual interference between signals, and improves the communication and sensing performance of the optical cable; the installation part of the sheath adopts an open structure, which can effectively disperse stress when the optical cable is subjected to lateral pressure, so that the optical fiber will not be directly affected, improving the compressive performance of the optical cable, and the open structure enables the optical fiber or optical fiber bundle to be directly inserted into the arc channel without damaging the sheath, reducing the complexity and time cost of construction and maintenance. In addition, when a fault occurs in the optical fiber unit, the open structure facilitates the quick positioning and replacement of the damaged optical fiber unit without the need to strip or replace the entire optical cable, effectively reducing the fault repair cost of the optical cable.

[0026] Through the unique structural design of the butterfly-shaped sheath, the present invention realizes the independence of the optical fiber units and the optimization of the open installation part, effectively reduces signal interference, improves the compressive performance and environmental adaptability of the optical cable, simplifies the construction and maintenance process, and reduces the maintenance cost.

[0027] The present invention adopts a closed-loop series butterfly-shaped sheath structure, which distributes the communication optical fiber and the sensing optical fiber at the edges of the inner skeleton and the outer skeleton respectively, forming an independent space nesting, increasing the physical distance between the communication optical fiber and the sensing optical fiber, further enhancing the signal isolation effect, and having high practicability and economy. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments recorded in the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0029] Figure 1 It is an axonometric view of the communication and sensing integrated butterfly-shaped lead-in optical cable in the embodiment of the present invention;

[0030] Figure 2 is an exploded view of the outer skeleton in the embodiment of the present invention;

[0031] Figure 3 is a cross-sectional view of the integrated sensing and butterfly-shaped lead-in optical cable in the embodiment of the present invention;

[0032] Figure 4 is a schematic structural diagram of the sheath in the embodiment of the present invention;

[0033] Figure 5 is a schematic diagram of the outer skeleton and the inner skeleton forming the first cavity and the second cavity in the embodiment of the present invention;

[0034] Figure 6 is Figure 3 a partial enlarged view of part A of

[0035] Figure 7 is a schematic structural diagram of the single-piece outer skeleton in the embodiment of the present invention.

[0036] Reference numerals: 1, first reinforcing member; 2, inner skeleton; 2a, second cavity; 21, third protrusion; 3, optical cable layer; 3a, butterfly unit; 31, sheath; 311, main body part; 312, mounting part; 312a, fixed end; 312b, free end; 312c, arc channel; 32, communication unit; 33, second reinforcing member; 34, sensing unit; 4, outer skeleton; 4a, first cavity; 41, support ring; 42, first protrusion; 42a, outer convex arc surface; 42b, sealing plate; 42c, closed cavity; 43, second protrusion; 43a, auxiliary heat dissipation cavity; 44, thermally conductive silica gel sheet; 5, outer protective layer. Detailed implementation manners

[0037] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments.

[0038] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there can also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are only for the purpose of illustration and do not represent the only implementation manner.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this invention belongs. The terms used in the description of this invention are for the purpose of describing specific embodiments only and are not intended to limit the invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0040] As Figures 1 to 7 shown, the synesthesia integrated butterfly-shaped fiber optic cable for introduction includes: a first strengthening member 1, and an inner skeleton 2, an optical cable layer 3, an outer skeleton 4, and an outer protective layer 5 that are sequentially arranged outside the first strengthening member 1 from inside to outside;

[0041] The optical cable layer 3 includes a plurality of serially connected butterfly units 3a. The butterfly unit 3a includes a sheath 31, and a communication unit 32, a second strengthening member 33, and a sensing unit 34 that are sequentially arranged along the long axis direction of the sheath 31. The sheath 31 includes a main body portion 311 for installing the second strengthening member 33, and installation portions 312 that are symmetric about the center and arranged on both sides of the main body portion 311;

[0042] One end of the installation portion 312 is fixed to the main body portion 311, and the free end 312b is bent reversely and extended to form an arc channel 312c. The diameter of the arc channel 312c is greater than the opening distance between the fixed end 312a and the free end 312b of the installation portion 312. The communication unit 32 and the sensing unit 34 are installed in the arc channel 312c, and each of them includes a sheath layer, an optical fiber or an optical fiber bundle arranged in the sheath layer, and a strengthening layer outside the sheath layer.

[0043] In the present invention, the structural design of the butterfly-shaped sheath 31 makes the optical fiber units independent of each other, reduces the mutual interference between signals, and improves the communication and sensing performance of the optical cable; and the installation portion 312 of the sheath 31 adopts an open structure, which can effectively disperse stress when the optical cable is subjected to lateral pressure, so that the optical fiber will not be directly affected, improving the compressive performance of the optical cable. Moreover, the open structure enables the optical fiber or the optical fiber bundle to be directly inserted into the arc channel 312c without damaging the sheath 31, reducing the complexity and time cost of construction and maintenance. In addition, when a failure occurs in the optical fiber unit, the open structure facilitates quick positioning and replacement of the damaged optical fiber unit without having to strip or replace the entire optical cable, effectively reducing the fault repair cost of the optical cable; in addition, the optical fiber in the arc channel 312c can avoid being directly impacted by external forces, and at the same time, when the optical cable is bent or squeezed, the arc channel 312c can also disperse stress, reducing the risk of damage to the optical fiber and providing better physical protection for the optical fiber.

[0044] The present invention realizes the independence of the optical fiber units and the optimization of the open installation portion 312 through the unique butterfly sheath 31 structural design, effectively reduces signal interference, improves the compression resistance and environmental adaptability of the optical cable, simplifies the construction and maintenance process, and reduces maintenance costs.

[0045] The present invention adopts a closed-loop series butterfly sheath 31 structure, so that the communication optical fiber and the sensing optical fiber are respectively distributed on the edges of the inner skeleton 2 and the outer skeleton 4, forming independent spatial nesting, increasing the physical distance between the communication optical fiber and the sensing optical fiber, further enhancing the signal isolation effect, and having high practicality and economy.

[0046] like Figure 5 As shown, the annular surfaces of the outer skeleton 4 and the inner skeleton 2 facing the optical cable layer 3 are respectively provided with a plurality of first cavities 4a and a plurality of second cavities 2a, and the first cavities 4a and the second cavities 2a are staggered along the circumferential direction; the cavity structure is utilized to provide a preset installation space for the butterfly unit 3a, and the installer does not need to perform complicated adjustment and positioning operations, making the installation process simpler and faster, reducing the installation difficulty and time cost, and the staggered cavity structure can provide better support and fixing effect for the butterfly unit 3a. This structure can effectively reduce the displacement or vibration of the butterfly unit 3a caused by external force during the use of the optical cable, thereby ensuring the stability of the communication and sensing functions.

[0047] The end of the butterfly unit 3a located at the communication unit 32 is embedded in the second cavity 2a to form a communication fiber layer, and the end located at the sensing unit 34 is embedded in the first cavity 4a to form a sensing fiber layer. The communication fiber layer is located in the inner circle, away from the external electromagnetic interference source, which can effectively reduce the interference of the external environment on the communication signal and improve the communication quality; while the sensing fiber layer is located in the periphery, although it may be subject to a certain degree of interference, since its main function is to sense environmental changes (such as temperature, pressure, etc.), this interference has little effect on its function, and since the sensing fiber is mainly used for environmental monitoring, it usually has more connection points, and setting it in the periphery can facilitate the operation of construction personnel and reduce construction time and cost.

[0048] In the preferred embodiment of the present invention, the openings of the two mounting parts 312 in the first cavity 4a or the second cavity 2a are arranged opposite to each other. The combination of the cavity structure and the mounting part 312 enables the mounting part 312 to better disperse stress when the optical cable is subjected to external forces such as stretching and bending, thereby reducing damage caused by stress concentration and enhancing the structural stability of the entire optical cable layer 3.

[0049] In the present invention, the outer skeleton 4 includes a split support ring 41 and a plurality of first protrusions 42 provided on the inner wall between the seams of the support ring 41 when joined in pairs. The split support ring 41 can be conveniently sleeved on or disassembled from the outside without a complex assembly process, and each part can be replaced individually without replacing the entire support ring 41, reducing the maintenance cost. In order to enhance the sealing effect, the splicing surface on the middle cross-section can be adhesively sealed with epoxy resin.

[0050] The side walls of the two first protrusions 42 forming the first cavity 4a are outwardly convex arc surfaces 42a, and the outwardly convex arc surfaces 42a are tangent to the outer edge of the mounting portion 312 embedded in the first cavity 4a, so that the outwardly convex arc surfaces 42a can closely fit the outer edge of the mounting portion 312 to form a good contact relationship, and the free end 312b abuts against the fixed end 312a of the other mounting portion 312.

[0051] When the outer skeleton 4 is subjected to an external radial force, the free end 312b of the outwardly convex arc surface 42a will be subjected to a force, and the force will be transmitted through the outwardly convex arc surface 42a to the fixed end 312a of the mounting portion 312, pushing the fixed end 312a of the mounting portion 312 to generate a certain displacement. At the same time, the free end 312b of the outwardly convex arc surface 42a will drive the entire sheath 31 to rotate slightly. At this time, the fixed ends 312a of the two mounting portions 312 on the main body portion 311 rotate at an angle due to the force, driving the mounting portion 312 to rotate in the opposite direction along the cavity side wall. The free end 312b and the fixed end 312a of the mounting portion 312 tighten towards the inside of the arc-shaped channel 312c, clamping the optical fiber unit in the arc-shaped channel 312c. Through the above actions, the mounting portion 312 can better fix the optical fiber unit after being stressed, reducing loosening or displacement caused by external forces during use, and improving the stability of the entire optical cable structure. In addition, the tightening action of the mounting portion 312 makes the opening gap smaller, effectively reducing the influence of the external environment on the inside of the optical cable, such as the entry of impurities such as dust and moisture, thereby improving the sealing and protection performance of the optical cable.

[0052] Based on the above embodiments, sealing plates 42b are provided at the free ends 312b of the two outwardly convex arc surfaces 42a, forming a closed cavity 42c inside the first protrusion 42. The structure of the first protrusion 42 formed by the sealing plates 42b and the two outwardly convex arc surfaces 42a can disperse the external force over a larger area, avoiding local stress concentration, reducing the direct pressure on the optical fiber unit, and the air in the closed cavity 42c has a certain elasticity. When the optical cable is subjected to an external force, the air can undergo elastic deformation, playing a buffering role and reducing the impact of the external force on the optical fiber unit to protect the optical fiber from damage.

[0053] In addition, the provision of the closed cavity 42c optimizes the heat dissipation path, enabling the heat dissipation of the optical fiber units within the first cavity 4a and the second cavity 2a, and improving the heat dissipation efficiency of the optical cable. Specifically, when the optical fiber unit within the first cavity 4a generates heat, the heat is transferred to the inner arc surface of the outer skeleton 4 through heat conduction, then transferred to the outer protective layer 5 through the outer skeleton 4, and finally dissipated to the external environment; when the optical fiber unit within the second cavity 2a generates heat, the heat is first transferred to the peripheral wall of the closed cavity 42c, and the heat is carried to the inner arc surface of the outer skeleton 4 where the closed cavity 42c is located by the air convection within the closed cavity 42c. Subsequently, the heat is transferred to the outer protective layer 5 through the outer skeleton 4 and finally dissipated to the external environment.

[0054] To further improve the heat dissipation efficiency, as Figures 5 - 6 shown, the sealing plate 42b is provided with a second protrusion 43 facing the second cavity 2a, and gaps are left between the two side walls of the second protrusion 43 and the fixed ends 312a of the two mounting portions 312; the existence of the gaps optimizes the air flow path, increases the heat conduction area, helps to form convective heat dissipation, and improves the heat conduction efficiency.

[0055] Further preferably, an auxiliary heat dissipation cavity 43a is provided within the second protrusion 43, and the area of the auxiliary heat dissipation cavity 43a is smaller than that of the closed cavity 42c; since the area of the auxiliary heat dissipation cavity 43a is small, heat is more likely to concentrate therein, thus forming a relatively high temperature gradient. When the heat is transferred from the auxiliary heat dissipation cavity 43a to the larger closed cavity 42c, the existence of the temperature gradient will accelerate the heat conduction. In addition, a heat-conducting silica gel sheet 44 is provided on the cross-section of the sealing plate 42b between the closed cavity 42c and the auxiliary heat dissipation cavity 43a. The heat-conducting silica gel sheet 44 further reduces the thermal resistance and improves the heat transfer efficiency.

[0056] In the preferred embodiment of the present invention, a third protrusion 21 formed between two adjacent second cavities 2a has a downward concave outer ring surface facing the center of the circle; the third protrusion 21 is correspondingly arranged with the first cavity 4a, and the outer ring surface is tangent to the outer cylindrical surfaces of two adjacent sheaths 31. The sheaths 31 on the series-connected multiple butterfly units 3a form a reinforcing layer in the circumferential direction, and the outer ring surface of the third protrusion 21 plays a buffering role for the reinforcing layer.

[0057] In the present invention, the inner skeleton 2, the outer skeleton 4, and the sheath 31 are made of one of polyethylene, polyvinyl chloride, polyurethane, or low-smoke and halogen-free flame-retardant polyolefin. The selection of these materials can be optimized according to the specific application scenarios and performance requirements of the optical cable, providing good mechanical protection, fire resistance, and environmental protection characteristics. Moreover, both the first strengthening member 1 and the second strengthening member 33 are made of non-metallic strengthening members, which have good tensile properties and can withstand large tensile forces, ensuring the mechanical stability of the optical cable during laying and use. Compared with traditional metallic strengthening members, it can significantly reduce the weight of the optical cable, which not only facilitates the laying and installation of the optical cable but also reduces the transportation and construction costs.

[0058] Those skilled in the art should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A synaesthetic integrated butterfly-shaped fiber optic cable for introduction, characterized in that, Including: A first reinforcing member, and an inner skeleton, an optical cable layer, an outer skeleton, and an outer protective layer that are sequentially arranged outside the first reinforcing member from the inside out; The optical cable layer includes a plurality of tandem butterfly units. Each butterfly unit includes a sheath, and a communication unit, a second reinforcing member, and a sensing unit that are sequentially arranged along the long axis direction of the sheath. The sheath includes a main body portion for mounting the second reinforcing member, and mounting portions that are centrally symmetrically arranged on both sides of the main body portion; One end of the mounting portion is fixed to the main body portion, and the free end is bent reversely and extended to form an arc channel. The diameter of the arc channel is greater than the opening distance between the fixed end and the free end of the mounting portion. The communication unit and the sensing unit are mounted in the arc channel, and each of them includes a sheath layer, one optical fiber or an optical fiber bundle arranged in the sheath layer, and a reinforcing layer outside the sheath layer; A plurality of first cavities and a plurality of second cavities are respectively arranged on the annular surfaces of the outer skeleton and the inner skeleton facing the optical cable layer. The first cavities and the second cavities are staggered in the circumferential direction; The butterfly unit is embedded in the second cavity at the end of the communication unit and embedded in the first cavity at the end of the sensing unit.

2. The integrated synesthesia butterfly-shaped fiber optic cable according to claim 1, characterized in that, The openings of the two mounting portions in the first cavity or the second cavity are arranged opposite to each other.

3. The integrated sensing and communication butterfly-shaped fiber optic cable according to claim 1, characterized in that, The outer skeleton includes a split support ring, and a plurality of first protrusions arranged on the inner wall between the two seams of the support ring; The side walls of the two first protrusions forming the first cavity are convex arc surfaces. The convex arc surfaces are tangent to the outer edges of the mounting portions embedded in the first cavity, and the free ends abut against the fixed ends of the other mounting portions.

4. The integrated tactile-visual butterfly-shaped fiber optic cable according to claim 3, characterized in that, Sealing plates are provided at the free ends of the two convex arc surfaces, and a closed cavity is formed in the first protrusion.

5. The integrated tactile and visual butterfly-shaped fiber optic cable according to claim 4, characterized in that, The sealing plate is provided with a second protrusion facing the second cavity; Gaps are left between the two side walls of the second protrusion and the fixed ends of the two mounting portions.

6. The integrated sensing and communication butterfly-shaped fiber optic cable introduced according to claim 5, characterized in that, An auxiliary heat dissipation cavity is provided in the second protrusion, and the area of the auxiliary heat dissipation cavity is smaller than the area of the closed cavity; A heat-conducting silica gel sheet is arranged on the section of the sealing plate between the closed cavity and the auxiliary heat dissipation cavity.

7. The integrated tactile and visual butterfly-shaped fiber optic cable according to claim 1, characterized in that, A third protrusion formed between two adjacent second cavities has a concave outer ring surface facing the center of the circle; The third protrusion is arranged corresponding to the first cavity, and the outer ring surface is tangent to the outer cylindrical surfaces of two adjacent sheaths.

8. The integrated synesthesia butterfly-shaped fiber optic cable according to claim 1, characterized in that The inner skeleton, the outer skeleton, and the sheath are made of one material selected from polyethylene, polyvinyl chloride, polyurethane, or low-smoke halogen-free flame-retardant polyolefin.

9. The integrated synaesthesia butterfly-shaped fiber optic cable according to claim 1, characterized in that, Both the first reinforcing member and the second reinforcing member are made of non-metallic reinforcing members.

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