Optical Fiber Cable with GFRP Tension Member and Low Friction Jacket
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing optical fiber cables face difficulties in flexible installation into electric conduits due to high flexural rigidity requirements and potential induction from metal components, leading to increased outer diameters and reduced flexibility.
Innovation Solution
An optical fiber cable design featuring a glass fiber reinforced plastic (GFRP) tension member with a diameter between 0.7 mm and 1 mm, and a jacket with a friction coefficient of 0.3 or less, providing a rectangular cross-section for improved flexibility and ease of installation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If steel wire is used as tension member to provide high flexural rigidity, then the optical fiber cable has high flexural rigidity, but the cable may receive induction from electric power wire and requires grounding connection
Solution Approach 1:
The patent removes the metal steel wire tension member from the optical fiber cable structure and replaces it with a non-metallic GFRP tension member. This extraction of the harmful metal component eliminates the induction problem while maintaining the necessary mechanical strength through the glass fiber reinforced plastic material.
Solution Approach 2:
The patent uses glass fiber reinforced plastic (GFRP) as a composite material to replace the traditional steel wire. The GFRP combines glass fibers for structural strength with plastic matrix for electrical insulation, providing both flexural rigidity and immunity to electromagnetic induction.
2Object-affected harmful factors
If nonmetallic tension member such as aramid fiber reinforced plastic is used to eliminate metal, then the cable avoids induction, but the flexural rigidity is lower and the diameter of tension member must be increased
Solution Approach 1:
The patent optimizes the diameter parameter of the GFRP tension member to fall within 0.7mm to 1mm, which is a specific range that provides sufficient flexural rigidity while maintaining flexibility for installation. This parameter optimization allows the non-metallic material to achieve performance comparable to or better than traditional steel wire.
3Strength
If diameter of tension member is increased to improve flexural rigidity, then the flexural rigidity improves, but the outer diameter of optical fiber cable increases and flexibility decreases
Solution Approach 1:
The patent specifies that the GFRP tension member diameter should be 0.7mm to 1mm, which is a carefully selected parameter range. This optimization provides sufficient flexural rigidity for structural support while keeping the overall cable diameter small enough to maintain flexibility and ease of installation in existing conduits.
4Strength
If conventional optical fiber cable with metal tension member is used, then the cable has structural strength, but the installation into existing pipe conduit is difficult without installation rod
Solution Approach 1:
The patent optimizes the overall cable dimensions by controlling the jacket major axis to 4mm or less and minor axis to 2.8mm or less. This dimensional optimization, combined with the low friction coefficient jacket, enables the cable to be pushed into existing pipe conduits without requiring installation rods or special installation tools.
Solution Approach 2:
The patent uses a jacket with friction coefficient of 0.3 or less, which provides a low-friction surface that facilitates smooth insertion into pipe conduits. This low-friction characteristic, combined with the optimized dimensions, allows easy installation while maintaining the structural integrity provided by the GFRP tension members.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The design enables flexible and efficient pushing installation into pipe conduits with a smaller outer diameter, maintaining high flexural rigidity and flexibility, thus overcoming the limitations of previous metallic tension members.
Implementation Method 1
the jacket has a friction coefficient of 0.3 or less
Data Source
Figure 1~2
Figure 3~4
AI summary
An optical fiber cable includes an optical fiber core wire; a pair of tension members extending parallel to each other in an extension direction of the optical fiber core wire, sandwiching the optical fiber core wire; and a rectangular jacket covering the optical fiber core wire and the pair of tension members, and in a cross-section orthogonal to the extension direction, having a major axis in a facing direction of the tension members and a minor axis in a direction orthogonal to the facing direction, wherein each of the tension members is glass fiber reinforced plastic having a diameter in a range of 0.7 mm or more and 1 mm or less, and the jacket has a friction coefficient of 0.3 or less, the major axis of 4 mm or less, and the minor axis of 2.8 mm or less.