An anti-interference shield signal control line

Abstract

This invention provides an anti-interference shielded signal control line, comprising a central conductor and multiple optical fibers, the outer surfaces of which are jointly fixedly connected with fiber grease; it also includes a buffer protective sleeve to cover the central conductor, optical fibers, and fiber grease; the inner wall of the buffer protective sleeve is provided with a buffer strip extending along the direction of the optical fibers, the buffer strip being hollow and filled with phase change material; an inner sheath is fitted on the outer side of the buffer protective sleeve; the inner sheath is composed of multiple independent annular segments arranged along the optical fiber axis, each annular segment having an annular flange at its end, and adjacent annular segments having annular grooves at their ends that match the annular flanges, the annular flanges being inserted into the annular grooves to form a sliding connection structure, with a reserved expansion gap, allowing the annular segments to slide and swing relative to each other axially. By setting a hollow buffer strip filled with phase change material, the micro-environment temperature around the optical fiber is adjusted, mitigating the impact of drastic temperature changes.

Description

Technical Field

[0001] This utility model relates to the field of signal control line technology, specifically to an anti-interference shielded signal control line. Background Technology

[0002] Composite optical cables, as a new type of transmission line integrating optical fiber and copper power transmission wire, are widely used in broadband access network systems, solving comprehensive problems related to broadband access, equipment power consumption, and signal transmission. However, with the continuous expansion of application scenarios, composite optical cables face increasingly severe environmental challenges, especially under extreme climatic conditions involving high and low temperature cycles.

[0003] In existing composite optical cables, the internal structure typically employs tight stacking or simple twisting. With this structure, when the ambient temperature changes drastically, significant internal stress arises between the different materials (such as optical fibers, fiber optic paste, fillers, and sheaths) due to differences in their coefficients of thermal expansion. For example, at high temperatures, the materials expand, generating strong compressive stress in the rigid protective layers such as the inner and outer sheaths; at low temperatures, the materials contract, generating tensile stress. These stresses eventually concentrate and act on the optical fiber, causing micro-bending and increasing optical signal transmission loss, severely impacting communication quality and efficiency. Furthermore, repeated stress cycles can lead to delamination between the optical fiber and fiber optic paste, and even cracking and permanent damage to the internal structure of the cable, significantly shortening the product's lifespan.

[0004] While some existing technologies improve the mechanical damage resistance of optical cables by increasing sheath thickness or using tougher materials, this does not fundamentally solve the problem of internal stress caused by thermal expansion and contraction. These rigid reinforcement measures may actually make stress release more difficult, leading to more pronounced stress concentration problems. Therefore, designing a composite optical cable structure that can effectively buffer and disperse temperature stress, thereby improving the stability and durability of optical cables under extreme temperature cycling, without relying on complex chemical materials or expensive temperature control devices, has become an urgent problem to be solved in this technical field. Utility Model Content

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide an anti-interference shielded signal control line. Through its unique structural design, it can effectively buffer and release internal stress caused by temperature changes, protect the optical fiber from damage, and ensure the stability and reliability of signal transmission.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: An anti-interference shielded signal control line includes a central conductor and multiple optical fibers, the outer surfaces of the multiple optical fibers being fixedly connected with fiber grease; characterized in that it further includes a buffer protective sleeve for covering the central conductor, optical fibers, and fiber grease. The inner wall of the buffer protective sleeve is provided with a buffer strip extending along the direction of the optical fiber. The buffer strip is hollow and filled with phase change material. The outer side of the buffer protective sleeve is fitted with an inner protective sleeve. The inner sheath is composed of multiple independent annular segments arranged along the optical fiber axis. Each annular segment has an annular flange at its end, and adjacent annular segments have annular grooves at their ends that match the annular flanges. The annular flanges are inserted into the annular grooves to form a sliding connection structure, and an expansion gap is reserved to allow relative sliding and swinging between the annular segments in the axial direction.

[0007] As a further optimization of this utility model: The outer side of the inner sheath is spirally wound with an alloy strip to enhance the overall compressive and tensile strength and electromagnetic shielding performance of the cable.

[0008] As a further optimization of this utility model: A metal rectangular ring is also fixedly installed on the annular segment to enhance the rigidity of the segment structure and can serve as a connection point for grounding or signal enhancement.

[0009] As a further optimization of this utility model: A foamed filling layer is provided between the alloy strip and the inner sheath. This foamed layer is elastic and can further absorb and buffer external impact and internal stress, while reducing the weight of the cable.

[0010] As a further optimization of this utility model: A rubber insulating sleeve is provided on the outer side of the alloy strip, and the inner wall of the rubber insulating sleeve is in contact with the outer surface of the alloy strip to provide final electrical insulation and environmental protection.

[0011] Compared with the prior art, the present invention has the following significant advantages: 1. Temperature stress buffering and release: By setting a hollow buffer strip filled with phase change material, the micro-environment temperature around the optical fiber is adjusted by utilizing the characteristic of phase change material to absorb or release a large amount of heat at a specific temperature, thus mitigating the impact of drastic temperature changes.

[0012] 2. Axial stress compensation and flexibility: The inner sheath adopts a segmented sliding connection structure. When the cable expands or contracts axially due to temperature changes, each annular segment can slide relative to each other or swing slightly through the reserved expansion gap. This design decomposes concentrated, long-distance tensile or compressive stress into the gaps between each segment, effectively preventing stress from being directly transmitted to the fragile internal optical fiber and significantly reducing the risk of micro-bending loss in the optical fiber.

[0013] 3. Improved reliability and service life: This utility model solves the core problem of thermal stress concentration from a structural perspective, avoiding fiber damage and internal structural cracking, thereby ensuring the transmission quality of signals throughout the entire life cycle of the cable and greatly extending the service life of the product in harsh environments. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a three-dimensional structural cross-sectional view of an embodiment of the present utility model; Figure 2 This is a schematic diagram of the connection structure of the inner sheath in one embodiment of the present invention.

[0016] Explanation of reference numerals in the attached figures: 1. Center conductor; 2. Optical fiber; 3. Buffer protective sleeve; 4. Buffer strip; 5. Inner sheath; 6. Annular segment; 7. Annular flange; 8. Annular groove; 9. Alloy strip; 10. Metal rectangular ring; 11. Rubber insulating sleeve. Detailed Implementation

[0017] The accompanying drawings are for illustrative purposes only and should not be construed as limiting the scope of this patent. To better illustrate this embodiment, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product.

[0018] It will be understood by those skilled in the art that certain well-known structures and their descriptions may be omitted in the accompanying drawings. The technical solution of this utility model will be further described below with reference to the accompanying drawings and embodiments.

[0019] Example 1 Please see Figure 1 and Figure 2 This invention provides an anti-interference shielded signal control line, comprising a central conductor 1 and multiple optical fibers 2 arranged around the central conductor 1. The outer surfaces of the multiple optical fibers 2 are filled and fixed with fiber grease to form a stable optical fiber bundle. The central conductor 1 is used to transmit electrical energy or electrical signals.

[0020] In this embodiment, the core portion of the cable is encased in a buffer protective sleeve 3. Multiple buffer strips 4 are integrally formed or fixedly installed on the inner wall of the buffer protective sleeve 3 along the axial direction of the cable (i.e., the extension direction of the optical fiber 2). These buffer strips 4 are hollow structures, with their internal cavities filled with a phase change material. The phase change material can be paraffin wax, polyethylene glycol (PEG), or other materials that undergo a solid-liquid phase change within a preset operating temperature range (e.g., -40°C to 85°C). When the ambient temperature rises, the phase change material melts from a solid to a liquid state, absorbing a large amount of latent heat, thereby slowing down the rate of temperature increase within the cable; when the ambient temperature decreases, the phase change material solidifies from a liquid to a solid state, releasing latent heat, slowing down the rate of temperature decrease within the cable, thus acting as a temperature buffer and protecting the optical fiber 2 from drastic temperature changes.

[0021] The outer side of the buffer protective sleeve 3 is tightly fitted with the inner sheath 5. One of the key innovations of this utility model lies in the structure of the inner sheath 5. The inner sheath 5 is not a continuous, integral tube, but rather composed of multiple independent, short, annular segments 6 arranged and spliced ​​along the axial direction of the optical fiber 2. Figure 2 As shown, each annular segment 6 has an annular flange 7 at one end and an annular groove 8 at the other end that matches the shape and size of the annular flange 7. During assembly, the annular flange 7 of one annular segment 6 is inserted into the annular groove 8 of the adjacent annular segment 6, forming a sliding connection structure.

[0022] A small expansion gap is intentionally provided between the annular flange 7 and the annular groove 8. When the entire cable expands axially due to high temperature, the expansion gap between the various annular segments 6 will shrink, allowing the segments to approach each other; when it contracts axially due to low temperature, the segments can be pulled apart. This design gives the entire inner sheath 5 a certain degree of freedom of expansion and contraction in the axial direction, distributing the overall length change into hundreds or thousands of tiny gaps for absorption, thereby avoiding the direct application of tensile or compressive stress to the internal buffer protective sleeve 3 and optical fiber 2. At the same time, this connection structure also allows the segments to swing at small angles when the cable is bent, improving the cable's flexibility.

[0023] To further enhance mechanical properties and shielding effectiveness, one or more layers of alloy strip 9 are spirally wound around the outer side of the inner sheath 5. The alloy strip 9 can be made of aluminum, steel, or copper, providing strong compressive and tensile strength and forming a Faraday cage to effectively shield against external electromagnetic interference.

[0024] In some preferred embodiments, to improve specific performance, a metal rectangular ring 10 can be fixedly provided on the outer wall of the annular segment 6. This metal rectangular ring 10 can enhance the structural strength of the annular segment 6, prevent it from deforming under extreme pressure, and also further shield against external electromagnetic interference.

[0025] To further improve cushioning performance, a foam filler layer can be filled between the alloy strip 9 and the inner sheath 5. This foam filler layer, such as expanded polyethylene (PEF), is lightweight and highly elastic, capable of absorbing external impact energy without affecting the bending flexibility of the overall structure.

[0026] Finally, a tough and wear-resistant rubber insulating sleeve 11 is installed on the outside of the entire structure, with its inner wall tightly fitted to the outer surface of the alloy strip 9. The rubber insulating sleeve 11 provides final electrical insulation protection and can resist ultraviolet rays, chemical corrosion and physical abrasion, ensuring that the cable can work stably for a long time in various harsh environments.

[0027] Summary of working principles: When the anti-interference shielded signal control line is exposed to a temperature cycling environment: Radial stress and temperature buffering: Changes in ambient temperature are initially absorbed by the outer structure, including the rubber insulating sleeve 11, alloy strip 9, and foam filling layer. When temperature fluctuations are transmitted to the interior, the phase change material 6 in the buffer strip 4 begins to function, absorbing or releasing heat through phase change to stabilize the temperature field around the optical fiber 2 and reduce the magnitude of thermal expansion and contraction.

[0028] Axial stress relief: The macroscopic axial elongation or shortening of the entire cable caused by temperature changes is effectively mitigated by the segmented inner sheath 5. The stress causes the various annular segments 6 to slide slightly relative to each other within the expansion gap, thereby releasing the stress, preventing stress accumulation and transmission to the optical fiber 2, and protecting the stability of optical signal transmission.

[0029] In summary, this utility model, through the innovative design of the buffer strip and the segmented inner sheath, successfully solves the technical problem of performance degradation or even damage to composite optical cables caused by internal stress in variable temperature environments, and provides a highly reliable, long-life anti-interference shielded signal control line.

[0030] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating this utility model, and are not intended to limit the implementation of this utility model. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. An anti-interference shielded signal control line, comprising a central conductor and multiple optical fibers, wherein the outer surfaces of the multiple optical fibers are jointly fixedly connected with fiber optic grease; characterized in that, It also includes a buffer protective sleeve to cover the central conductor, optical fiber, and fiber optic paste; The inner wall of the buffer protective sleeve is provided with a buffer strip extending along the direction of the optical fiber. The buffer strip is hollow and filled with phase change material. The outer side of the buffer protective sleeve is fitted with an inner protective sleeve. The inner sheath is composed of multiple independent annular segments arranged along the optical fiber axis. Each annular segment has an annular flange at its end, and adjacent annular segments have annular grooves at their ends that match the annular flanges. The annular flanges are inserted into the annular grooves to form a sliding connection structure, and an expansion gap is reserved to allow relative sliding and swinging between the annular segments in the axial direction.

2. The anti-interference shielded signal control line according to claim 1, characterized in that, The outer side of the inner sheath is spirally wound with an alloy strip.

3. The anti-interference shielded signal control line according to claim 1, characterized in that, A metal rectangular ring is also fixedly installed on the annular segment.

4. The anti-interference shielded signal control line according to claim 2, characterized in that, A foamed filling layer is provided between the alloy strip and the inner sheath.

5. The anti-interference shielded signal control line according to claim 2, characterized in that, A rubber insulating sleeve is provided on the outer side of the alloy strip, and the inner wall of the rubber insulating sleeve is in contact with the outer surface of the alloy strip.

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