Optical Fiber Unit Coating Spiral Opening Disassembly

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing optical fiber units risk damaging internal fibers when being disassembled due to accidental tightening of bundle materials, especially when high-density mounting and side pressure are applied, leading to microbend loss.

Innovation Solution

An optical fiber unit with a coating having a Young's modulus of 400 MPa or less, formed from a thermoplastic or ultraviolet curing resin, and featuring a spiral opening that allows for easy deformation and disassembly without tightening, ensuring the internal fibers can be extracted without damage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Stability of the object's composition

If bundle materials are wound in a spiral shape and bonded at intersections to secure the optical fiber assembly, then the structural stability is improved, but the ease of disassembly deteriorates due to accidental tightening and potential fiber damage

Engineering Contradiction:
Improvestructural stabilityVSAvoidease of disassembly
Core Design Contradiction:
Stability of the object's compositionVSEase of operation

Solution Approach 1:

The invention extracts the harmful bonding function from the bundle materials by removing the adhesive coating. This allows the bundle materials to be easily separated from the optical fiber assembly during disassembly without causing fiber damage, while still providing structural stability through the spiral winding configuration alone

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The invention segments the binding function into two parts: the spiral winding provides structural stability while the adhesive bonding is completely removed. This segmentation allows the bundle materials to maintain positioning function without the harmful tightening effect that occurs with bonded intersections

Inventive Principle:
Principle #1Segmentation

2Productivity

If the optical fiber unit is mounted with high density, then the productivity is improved, but the reliability deteriorates due to side pressure causing bundle material tightening and microbend loss

Engineering Contradiction:
Improvemounting densityVSAvoidfiber integrity
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The invention converts the potential harm of side pressure into a beneficial effect by removing the adhesive bonding. When side pressure is applied during high-density mounting, the non-bonded bundle materials can flex and deform without tightening, actually protecting the optical fibers from microbend loss while maintaining mounting density

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

3Stability of the object's composition

If adhesive is applied to bundle materials to prevent loosening, then the stability is improved, but the ease of repair deteriorates due to difficulty in removing bonded materials

Engineering Contradiction:
Improveanti-looseningVSAvoidease of material removal
Core Design Contradiction:
Stability of the object's compositionVSEase of repair

Solution Approach 1:

The invention extracts the adhesive component entirely from the bundle material structure. The bundle materials rely solely on their spiral winding configuration for stability, which can be easily unwound and removed during repair without the complications of adhesive removal, while still preventing loosening through proper winding tension

Inventive Principle:
Principle #2Taking out (Extraction)

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 solution enables easy extraction of optical fibers without damage and allows for high-density mounting by preventing the bundle material from tightening, thus reducing microbend loss and facilitating the disassembly process.

Implementation Method 1

a coating 30 for covering the periphery of the assembly 20... an outer shape of the optical fiber unit can be easily deformed

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 2

formed from a thermoplastic or ultraviolet curing resin

Methodology Applied
Scientific EffectThermoplastic deformation: Melting

Implementation Method 3

formed from a thermoplastic or ultraviolet curing resin

Methodology Applied
Scientific EffectUltraviolet curing: Photopolymerisation

Data Source

PatentEP3705924B1Optical fiber unit and optical fiber cable
Publication Date: 2022.10.19 SUMITOMO ELECTRIC INDUSTRIES LTD
  • EP3705924B1 patent drawingFigure 1
  • EP3705924B1 patent drawingFigure 2~3
  • EP3705924B1 patent drawingFigure 4

AI summary

An optical fiber unit includes: an assembly in which a plurality of optical fiber ribbons in which a plurality of optical fibers are disposed in parallel are assembled; and a coating for covering the periphery of the assembly in a state of having a space inside. The coating is interrupted at a part in a circumferential direction of the optical fiber unit, and an opening part is formed.