Lightweight butterfly-shaped optical cable and preparation method thereof

Abstract

The invention discloses a lightweight butterfly-shaped optical cable and a preparation method thereof, and belongs to the technical field of photoelectric communication transmission. The light-weight butterfly-shaped optical cable comprises an optical fiber unit, an inner sheath, an outer sheath and at least two reinforcing pieces, the inner sheath wraps the periphery of the optical fiber unit, the two reinforcing members are embedded in the inner sheath, the two reinforcing members are symmetrically arranged by taking the optical fiber unit as a center, a plurality of spaced micropores are arranged in the inner sheath, the outer sheath wraps the inner sheath, and the outer sheath wraps the periphery of the optical fiber unit. And grooves are formed in the outer sheath and the inner sheath corresponding to the two side surfaces of the optical fiber unit. According to the light-weight butterfly-shaped optical cable provided by the embodiment of the invention, the lateral pressure resistance, the flexibility and the micro-bending resistance of the butterfly-shaped optical cable can be effectively improved, and the light weight of the sheath material is realized, so that the production cost is greatly reduced in batch production.

Description

Technical Field

[0001] This invention belongs to the field of optoelectronic communication transmission technology, specifically relating to a lightweight butterfly-shaped optical cable and its preparation method. Background Technology

[0002] With the rapid development of broadband technology, optical fiber communication technology has become a major component of modern communication due to its significant advantages such as high speed, large capacity, and low loss. As a branch of optical cables, the butterfly-shaped optical cable is named for its butterfly-like cross-sectional shape. It has internal reinforcing components and places optical fibers in the middle, forming a butterfly-like cable structure. The butterfly-shaped optical cable features a flat design, and its simple and compact structure, small overall size, and advantages make it easy to lay, cost-effective, and fast to install.

[0003] However, the existing butterfly optical cables have the following main problems: (i) the sheath material of the butterfly optical cable is used in large quantities, resulting in high cost in mass production; (ii) the overall texture of the butterfly optical cable is relatively hard, and when it is laid under stress, it is easy to directly transfer stress to the optical fiber, resulting in micro-bending loss. Summary of the Invention

[0004] In view of the above-mentioned defects or improvement needs of the existing technology, the present invention provides a lightweight butterfly optical cable and its preparation method. The purpose is to not only effectively improve the lateral pressure resistance, flexibility and micro-bending resistance of the butterfly optical cable, but also to achieve lightweight sheath material, thereby greatly reducing the production cost in mass production.

[0005] To achieve the above objectives, in a first aspect, the present invention provides a lightweight butterfly optical cable, the lightweight butterfly optical cable comprising an optical fiber unit, an inner sheath, an outer sheath, and at least two reinforcing members; The inner sheath wraps around the outer periphery of the optical fiber unit, and the two reinforcing members are embedded in the inner sheath and are symmetrically arranged with the optical fiber unit as the center. The inner sheath is provided with a plurality of spaced micro-holes, and the outer sheath covers the outer sheath. The outer sheath and the inner sheath on both sides of the optical fiber unit form grooves.

[0006] Optionally, the diameter of the micropores is 5-30 μm.

[0007] In a second aspect, the present invention provides a method for preparing a lightweight butterfly optical cable, the method being based on the lightweight butterfly optical cable described in the first aspect, the method comprising: Step S1: Mix the first sheath material with the modified montmorillonite evenly, and then melt-blend and extrude to granulate to obtain the second sheath material; Step S2: Place the second sheath material under constant temperature and humidity conditions for a unit of time, so that the second sheath material absorbs moisture to form a second water-absorbing sheath material; Step S3: The optical fiber unit and the two reinforcing members are pulled and fed into the double-layer co-extrusion die. At the same time, the first sheath material and the second water-absorbing sheath material are fed into the extruder for high-temperature melting, and then extruded and fed into the double-layer co-extrusion die to obtain the lightweight butterfly optical cable.

[0008] Optionally, prior to step S1, the preparation method further includes: Modified montmorillonite was obtained by spraying montmorillonite with an ethanol solution containing a silane coupling agent under high-speed stirring and then drying the treated montmorillonite at high temperature.

[0009] Optionally, the modified montmorillonite surface coverage is controlled at 50% to 70%.

[0010] Optionally, in step S2, the temperature is 22-28℃, the relative humidity is 20-80%RH, and the unit time is 8-48h.

[0011] Optionally, the moisture content of the second absorbent sheath material is 0.3-0.8% by mass.

[0012] Optionally, in step S1, the first sheath material includes polyethylene matrix resin, environmentally friendly halogen-free flame retardant, antioxidant, lubricant, and smoke suppressant. The first sheath material, by weight, comprises 70-80 parts of polyethylene matrix resin, 15-30 parts of environmentally friendly halogen-free flame retardant, 0.2-1 parts of antioxidant, 0.5-2 parts of lubricant, and 1-3 parts of smoke suppressant.

[0013] Optionally, in step S1, the first sheath material and the montmorillonite are measured in parts by weight, with the first sheath material comprising 90-100 parts and the montmorillonite comprising 1-6 parts.

[0014] Optionally, in step S3, the temperature of the extruder is 120-200°C.

[0015] The aforementioned improved technical features can be combined with each other as long as they do not conflict with each other.

[0016] In summary, the beneficial effects of the above-described technical solutions conceived by this invention compared with the prior art include: (1) In the lightweight butterfly optical cable provided in this embodiment of the invention, the inner sheath wraps around the outer periphery of the optical fiber unit, two reinforcing members are embedded in the inner sheath and are symmetrically arranged with the optical fiber unit as the center. The inner sheath is provided with multiple spaced micro-holes, and the outer sheath covers the outer sheath. Grooves are formed on both sides of the optical fiber unit corresponding to the outer and inner sheaths. The optical fiber unit performs communication transmission, the reinforcing members constitute the main load-bearing skeleton of the optical cable, the inner and outer sheaths protect the optical fiber unit, and the grooves facilitate the stripping of the optical fiber unit. Furthermore, since the inner sheath is provided with multiple spaced micro-holes, the multiple dispersed micro-holes effectively reduce the stiffness of the sheath, like a built-in "micro-spring array", which significantly improves the lateral pressure resistance, flexibility and micro-bending resistance of the butterfly optical cable, and realizes the lightweighting of the sheath material, thereby greatly reducing the production cost in mass production.

[0017] (2) Regarding the method for preparing a lightweight butterfly-shaped optical cable provided in this embodiment of the invention, in preparing the lightweight butterfly-shaped optical cable, firstly, the first sheath material is uniformly mixed with modified montmorillonite, and then melt-blended and extruded into granules to obtain the second sheath material. The modified montmorillonite can be uniformly dispersed in the second sheath material through melt-blending and extrusion granulation, while retaining some of its water absorption capacity, facilitating subsequent pre-loading of moisture. Next, the second sheath material is placed under constant temperature and humidity conditions for a unit of time, allowing it to absorb moisture and form a second water-absorbing sheath material, thereby pre-loading moisture into the masterbatch of the inner sheath, i.e., wetting and absorbing water. Finally, the optical fiber unit and two reinforcing members are pulled and fed into a double-layer co-extrusion die, while the first sheath material and the second water-absorbing sheath material are fed into an extruder for high-temperature melting, extruded, and then fed into the double-layer co-extrusion die to obtain the lightweight butterfly-shaped optical cable. In this process, when the second absorbent sheath material undergoes high-temperature melting and plasticization in the extruder, the trace amounts of water pre-adsorbed in the montmorillonite rapidly vaporize upon heating, generating instantaneous localized pressure. This pressure is enveloped and constrained by the surrounding highly viscoelastic plastic melt. Similarly, due to the uniform distribution and small amount of water, vaporization forms a large number of small, independent, and uniformly dispersed closed micropores in the plastic matrix. These dispersed micropores effectively reduce the stiffness of the sheath, acting like a built-in "micro-spring array," significantly improving the lateral pressure resistance, flexibility, and micro-bending resistance of the butterfly optical cable. This also achieves lightweighting of the sheath material, thereby greatly reducing production costs in mass production. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a lightweight butterfly optical cable provided in an embodiment of the present invention; Figure 2 This is a flowchart of a method for preparing a lightweight butterfly-shaped optical cable according to an embodiment of the present invention.

[0019] In all the accompanying drawings, the same reference numerals denote the same technical features, specifically: 1. Fiber optic unit; 2. Inner sheath; 21. Micropore; 3. Outer sheath; 4. Reinforcing member; 5. Groove; 6. Enhancement member. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0021] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0022] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0023] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0024] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0025] Example: Figure 1 This is a schematic diagram of the structure of a lightweight butterfly optical cable provided in an embodiment of the present invention, as shown below. Figure 1 As shown, the lightweight butterfly optical cable includes an optical fiber unit 1, an inner sheath 2, an outer sheath 3, and at least two reinforcing members 4.

[0026] The inner sheath 2 wraps around the outer periphery of the optical fiber unit 1. Two reinforcing members 4 are embedded in the inner sheath 2 and are arranged symmetrically with the optical fiber unit 1 as the center. The inner sheath 2 is provided with multiple spaced micro-holes 21. The outer sheath 3 covers the outer sheath 2. The outer sheath 3 and the inner sheath 2 on both sides of the optical fiber unit 1 form grooves 5.

[0027] In the lightweight butterfly-shaped optical cable provided in this embodiment of the invention, the inner sheath 2 wraps around the outer periphery of the optical fiber unit 1, and two reinforcing members 4 are embedded in the inner sheath 2 and arranged symmetrically with respect to the optical fiber unit 1. The inner sheath 2 has multiple spaced micro-holes 21, and the outer sheath 3 covers the outer sheath 2. Grooves 5 are formed on both sides of the optical fiber unit 1 corresponding to the outer sheath 3 and the inner sheath 2. The optical fiber unit 1 performs communication transmission, the reinforcing members 4 constitute the main load-bearing skeleton of the optical cable, the inner sheath 2 and the outer sheath 3 protect the optical fiber unit 1, and the grooves 5 facilitate the stripping of the optical fiber unit 1.

[0028] Furthermore, since the inner sheath 2 is provided with multiple spaced micropores 21, the multiple dispersed micropores 21 effectively reduce the stiffness of the sheath, like a built-in "micro-spring array", which significantly improves the lateral pressure resistance, flexibility and micro-bending resistance of the butterfly optical cable, and realizes the lightweighting of the sheath material, thereby greatly reducing the production cost in mass production.

[0029] In other words, the lightweight butterfly optical cable provided by the embodiments of the present invention can not only effectively improve the lateral pressure resistance, flexibility and micro-bending resistance of the butterfly optical cable, but also achieve lightweight sheath material, thereby greatly reducing production costs in mass production.

[0030] For example, the reinforcing member 4 can be FRP (glass fiber reinforced plastic rod) or steel wire.

[0031] It should be noted that this lightweight butterfly-shaped optical cable simply adds two layers to the existing sheath: an inner sheath 2 and an outer sheath 3. The overall thickness remains unchanged, thus not increasing production or transportation costs. Furthermore, incorporating multiple uniformly distributed and independent micropores 21 within the inner sheath 2 effectively reduces the amount of sheath material used, aligning with green manufacturing and sustainable development principles.

[0032] For example, the thickness of the outer sheath 3 can be 0.05-0.1 mm, while the thickness of the inner sheath 2 can be 1.9-2.5 mm, that is, the thickness of the inner sheath 2 is much greater than that of the outer sheath 3.

[0033] In this embodiment, the diameter of the micropore 21 can be 5-30 μm.

[0034] It is easy to understand that if the micropores 21 are too large, they will affect the structural strength of the entire inner sheath 2, and thus the structural strength of the entire sheath layer. If the micropores 21 are too small, they will be difficult to process and will have little impact on the material used in the sheath layer and its resistance to micro-bending.

[0035] In one processing method of the present invention, the lightweight butterfly optical cable also includes a suspension wire, which is connected to the outer sheath 3 by a sling. The suspension wire includes a reinforcing member 6 and a sheath layer, which serves to bear the load. The sheath layer also includes an inner sheath and an outer sheath. The inner sheath is also provided with a plurality of spaced micro-holes 21, thereby further reducing production costs.

[0036] For example, the reinforcement 6 can be FRP (glass fiber reinforced plastic rod) or steel wire.

[0037] Figure 2 This is a flowchart of a method for preparing a lightweight butterfly-shaped optical cable according to an embodiment of the present invention, as shown below. Figure 2 As shown, the fabrication method is based on the aforementioned lightweight butterfly optical cable, and the fabrication method includes: Step S1: Mix the first sheath material with the modified montmorillonite evenly, and then melt-blend and extrude to obtain the second sheath material.

[0038] Among them, montmorillonite is nanoscale.

[0039] For example, the temperature of melt blending is controlled at 130-190°C.

[0040] Step S2: Place the second sheath material under constant temperature and humidity conditions for a unit of time so that the second sheath material absorbs moisture to form a second water-absorbing sheath material.

[0041] In this embodiment, in step S2, the temperature is 22-28℃, the relative humidity is 20-80%RH, and the unit time is 8-48h, thereby ensuring that the second sheath material fully absorbs water to form the second water-absorbing sheath material.

[0042] Correspondingly, the moisture content of the second absorbent sheath material is controlled at 0.3-0.8% by mass.

[0043] For example, a moisture meter is used to monitor the second absorbent sheath material. When the overall moisture content of the masterbatch is monitored to be stable within the target range of 0.3% to 0.8% (by mass), the pre-loading of moisture is considered complete.

[0044] Step S3: After pulling the optical fiber unit 1 and the two reinforcing members 4, they are fed into the double-layer co-extrusion mold. At the same time, the first sheath material and the second water-absorbing sheath material are fed into the extruder for high-temperature melting, and after extrusion, they are fed into the double-layer co-extrusion mold to obtain a lightweight butterfly optical cable.

[0045] The extruder temperature is 120-200℃. The first sheath material is extruded to form the outer sheath 3, while the second absorbent sheath material is simultaneously extruded to form the inner sheath 2.

[0046] In the preparation method of the lightweight butterfly optical cable provided by the embodiments of the present invention, the first sheath material is uniformly mixed with modified montmorillonite, and then melt-blended and extruded to obtain a second sheath material. The modified montmorillonite, through melt-blending and extrusion granulation, can be uniformly dispersed in the second sheath material while retaining some of its water absorption capacity, facilitating subsequent pre-loading of moisture. Next, the second sheath material is placed under constant temperature and humidity conditions for a unit of time to allow it to absorb moisture and form a second water-absorbing sheath material, thereby pre-loading moisture into the masterbatch of the inner sheath 2, i.e., wetting and water absorption.

[0047] Finally, the optical fiber unit 1 and two reinforcing members 4 are pulled and fed into a double-layer co-extrusion die. Simultaneously, the first sheath material and the second water-absorbing sheath material are fed into an extruder for high-temperature melting, and then extruded and fed into the double-layer co-extrusion die to obtain a lightweight butterfly-shaped optical cable. During the high-temperature melting and plasticizing of the second water-absorbing sheath material in the extruder, the trace amounts of water pre-adsorbed in the montmorillonite rapidly vaporize upon heating, generating instantaneous local pressure. This pressure is enveloped and constrained by the surrounding highly viscoelastic plastic melt. Due to the uniform distribution and small amount of water, vaporization forms numerous small, independent, and uniformly dispersed closed micropores 21 within the plastic matrix. These dispersed micropores 21 effectively reduce the stiffness of the sheath, acting like a built-in "micro-spring array," significantly improving the butterfly-shaped optical cable's resistance to lateral pressure, flexibility, and micro-bending performance, and achieving lightweight sheath material, thereby greatly reducing production costs in mass production.

[0048] In other words, the method for preparing a lightweight butterfly optical cable provided by the embodiments of the present invention can not only effectively improve the lateral pressure resistance, flexibility and micro-bending resistance of the butterfly optical cable, but also achieve lightweight sheath material, thereby greatly reducing production costs in mass production.

[0049] It is easy to understand that by using a double-layer co-extrusion die technology, an extremely thin, dense layer, namely the outer sheath 3, is simultaneously extruded on the outside of the inner sheath 2 while it is being extruded. This dense layer can effectively seal the micropores 21, improving surface smoothness and wear resistance.

[0050] In this embodiment, before step S1, the preparation method further includes: Modified montmorillonite was obtained by spraying montmorillonite with an ethanol solution containing a silane coupling agent under high-speed stirring and then drying the treated montmorillonite at high temperature.

[0051] In the above embodiments, the surface treatment of montmorillonite through the above steps can not only effectively disperse it in the subsequent granulation after blending, but also control its water absorption performance. That is, the montmorillonite is standardized to control the subsequent water absorption constant, so as to avoid large differences in the water absorption performance of different batches of montmorillonite under different environments, which would lead to large fluctuations in the performance of optical cables.

[0052] For example, montmorillonite after drying treatment at 80-110°C.

[0053] Specifically, the modified montmorillonite surface coverage is controlled at 50%–70%. This coverage ensures effective dispersion of montmorillonite in the matrix while retaining some of its hydrophilicity.

[0054] In this embodiment, in step S1, the first sheath material includes polyethylene matrix resin, environmentally friendly halogen-free flame retardant, antioxidant, lubricant and smoke inhibitor. The first sheath material is in parts by weight: 70-80 parts polyethylene matrix resin, 15-30 parts environmentally friendly halogen-free flame retardant, 0.2-1 part antioxidant, 0.5-2 parts lubricant and 1-3 parts smoke inhibitor.

[0055] The first sheath material can be a low-smoke halogen-free flame-retardant polyolefin base material, and the environmentally friendly halogen-free flame retardant can be magnesium hydroxide, aluminum hydroxide or their compound; the lubricant can be calcium stearate, and the smoke inhibitor can be a molybdenum compound.

[0056] In addition, in step S1, the first sheath material and montmorillonite are measured by weight, with the first sheath material being 90-100 parts and the montmorillonite being 1-6 parts, indicating that the proportion of montmorillonite is relatively small.

[0057] The lightweight butterfly-shaped optical cable provided by this invention has the following advantages: 1. Cost advantage: Good processability and simple process. Only a controllable "wet treatment" step is added to the existing process. No complicated chemical foaming is required, which can also reduce the amount of sheath material used.

[0058] 2. Green and environmentally friendly: Due to the formation of the microporous structure, the apparent density of the sheath material is reduced by about 15%-25%, which effectively reduces the consumption of raw materials while ensuring the same outer diameter and mechanical properties of the butterfly optical cable.

[0059] 3. Excellent micro-bending resistance: The micro-hole 21 structure of the sheath is similar to a "micro-spring array". The size of the micro-hole 21 is 5-30μm, which improves the lateral pressure resistance by about 20-40%. The micro-bending loss of the optical cable is significantly reduced, which can effectively buffer external lateral pressure and reduce the stress transmitted to the optical fiber.

[0060] 4. The improved mechanical properties and increased flexibility of the optical cable make it easier to lay.

[0061] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A lightweight butterfly-shaped optical cable, characterized in that, The lightweight butterfly optical cable includes an optical fiber unit, an inner sheath, an outer sheath, and at least two reinforcing members; The inner sheath wraps around the outer periphery of the optical fiber unit, and the two reinforcing members are embedded in the inner sheath and are symmetrically arranged with the optical fiber unit as the center. The inner sheath is provided with a plurality of spaced micro-holes, and the outer sheath covers the outer sheath. The outer sheath and the inner sheath on both sides of the optical fiber unit form grooves.

2. The lightweight butterfly-shaped optical cable according to claim 1, characterized in that, The diameter of the micropores is 5-30 μm.

3. A method for preparing a lightweight butterfly-shaped optical cable, characterized in that, The preparation method is based on the lightweight butterfly optical cable according to any one of claims 1-2, and the preparation method includes: Step S1: Mix the first sheath material with the modified montmorillonite evenly, and then melt-blend and extrude to granulate to obtain the second sheath material; Step S2: Place the second sheath material under constant temperature and humidity conditions for a unit of time, so that the second sheath material absorbs moisture to form a second water-absorbing sheath material; Step S3: The optical fiber unit and the two reinforcing members are pulled and fed into the double-layer co-extrusion die. At the same time, the first sheath material and the second water-absorbing sheath material are fed into the extruder for high-temperature melting, and then extruded and fed into the double-layer co-extrusion die to obtain the lightweight butterfly optical cable.

4. The method for preparing a lightweight butterfly-shaped optical cable according to claim 3, characterized in that, Prior to step S1, the preparation method further includes: Modified montmorillonite was obtained by spraying montmorillonite with an ethanol solution containing a silane coupling agent under high-speed stirring and then drying the treated montmorillonite at high temperature.

5. The method for preparing a lightweight butterfly-shaped optical cable according to claim 4, characterized in that, The modified montmorillonite surface coverage was controlled at 50%–70%.

6. The method for preparing a lightweight butterfly-shaped optical cable according to claim 3, characterized in that, In step S2, the temperature is 22-28℃, the relative humidity is 20-80%RH, and the unit time is 8-48h.

7. The method for preparing a lightweight butterfly-shaped optical cable according to claim 3, characterized in that, The second absorbent sheath material has a moisture content of 0.3-0.8% by mass.

8. A method for preparing a lightweight butterfly-shaped optical cable according to any one of claims 3-7, characterized in that, In step S1, the first sheath material includes polyethylene matrix resin, environmentally friendly halogen-free flame retardant, antioxidant, lubricant, and smoke suppressant. The first sheath material is 70-80 parts by weight, 15-30 parts by weight, 0.2-1 parts by weight, 0.5-2 parts by weight, and 1-3 parts by weight.

9. A method for preparing a lightweight butterfly-shaped optical cable according to any one of claims 3-7, characterized in that, In step S1, the first sheath material and the montmorillonite are weighed in parts, with the first sheath material being 90-100 parts and the montmorillonite being 1-6 parts.

10. A method for preparing a lightweight butterfly-shaped optical cable according to any one of claims 3-7, characterized in that, In step S3, the temperature of the extruder is 120-200℃.

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