Binder Film for Fiber Optic Cable Core Constraint
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The use of binder yarns in fiber optic cable manufacturing limits the length of cable production, introduces attenuation in optical fibers due to stress concentrations, and slows down the manufacturing process, as they require frequent switching and can cause axial migration of buffer tubes, leading to inefficiencies and distortions.
Innovation Solution
A binder film system is introduced that surrounds the core of the fiber optic cable, with radial tension to prevent outward deflection and normal loading of core elements against the central strength member, eliminating the need for binder yarns and using water-absorbing powder particles to enhance coupling and water-blocking capabilities, allowing for continuous cable production and reduced attenuation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If binder yarns are used to constrain buffer tubes, then the buffer tubes are constrained in the reversals, but the manufacturing line must be stopped every 20 km to switch out bobbins, reducing efficiency
Solution Approach 1:
The patent replaces discrete binder yarns with a continuous binder film that wraps around the core elements. This film is supplied from a single large reel rather than multiple small bobbins, eliminating frequent stoppages for bobbin changes while maintaining the constraining function on buffer tubes throughout the manufacturing process
Solution Approach 2:
The binder film is applied continuously over the entire length of the cable being manufactured, rather than being applied in discrete sections by multiple yarn bobbins. This continuous application eliminates interruptions in the manufacturing process and maintains constant constraint on the buffer tubes
2Reliability
If binder yarns are used to constrain buffer tubes, then the buffer tubes are constrained, but binder yarns impart distortions or stress concentrations in the stranded buffer tubes, potentially resulting in attenuation of optical fibers
Solution Approach 1:
The binder film provides a smooth, continuous surface that contacts the buffer tubes without the localized pressure points created by binder yarns. This distributed contact eliminates stress concentrations and distortions that would otherwise cause optical fiber attenuation, while still providing effective constraint
Solution Approach 2:
Instead of using discrete yarn elements that create point contacts, the invention inverts the approach by using a continuous film that creates distributed surface contact. This reverses the stress distribution pattern from concentrated to distributed, eliminating the harmful effects
3Reliability
If binder yarns are used to constrain buffer tubes, then the buffer tubes are constrained, but application of binder yarns limits the speed of a stranding machine, depending upon allowable binder-yarn tension
Solution Approach 1:
The binder film can be applied at higher speeds than binder yarns because it is supplied from large reels rather than small bobbins. The continuous supply system eliminates the speed limitations imposed by bobbin size and the need for frequent changes, allowing the stranding machine to operate at optimal speeds
4Reliability
If binder yarns are used to constrain buffer tubes, then the buffer tubes are constrained, but the finite lengths of binder yarns on a bobbin limit the length of cable that can be manufactured without stopping
Solution Approach 1:
The binder film is supplied from a single large reel that can provide continuous material for much longer cable lengths than individual bobbins of binder yarn. This eliminates the need to stop manufacturing to change bobbins, enabling production of very long continuous cable lengths
Solution Approach 2:
The continuous supply of binder film from a large reel maintains uninterrupted constraint on the buffer tubes throughout the manufacturing process, allowing cable to be manufactured in long continuous lengths without stopping the production line for bobbin changes
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 binder film system enables continuous cable manufacturing, reduces optical fiber attenuation, and improves manufacturing efficiency by maintaining core elements in place during the process, preventing axial migration and distortion, thus enhancing the stability and integrity of the fiber optic cable.
Implementation Method 1
The binder film is in radial tension around the core such that the binder film opposes outwardly transverse deflection of the core elements
Implementation Method 2
the binder film loads the core elements normally to the central strength member such that contact between the core elements and central strength member provides coupling therebetween
Implementation Method 3
using water-absorbing powder particles to enhance coupling and water-blocking capabilities
Data Source
AI summary
A fiber optic cable includes a core and a binder film surrounding the core. The core includes a central strength member and core elements, such as buffer tubes containing optical fibers, where the core elements are stranded around the central strength member in a pattern of stranding including reversals in lay direction of the core elements. The binder film is in radial tension around the core such that the binder film opposes outwardly transverse deflection of the core elements.