Foamed Cable Conduit Reducing Weight and Cost

Solution Overview

Problem

Existing cable protection tubes for telecommunications and fiber optic cables are heavy and costly due to their solid thermoplastic construction, lacking sufficient stability and incurring high production and transportation expenses, while also requiring low friction and pressure-tightness for efficient cable routing.

Innovation Solution

A cable protection tube with a three-layer structure featuring a smooth-surfaced duct inner and outer wall and a foamed intermediate layer made of thermoplastic materials like polyethylene or polypropylene, where the foamed layer has a closed-cell design and a significant thickness, reducing weight and manufacturing costs while maintaining mechanical properties and pressure resistance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If solid thermoplastic material is used for cable protection tubes, then mechanical strength and stability are improved, but weight and production costs increase

Engineering Contradiction:

Improvemechanical strengthVSAvoidweight

Core Design Contradiction:

StrengthVSWeight of moving object

Solution Approach 1:

The duct wall is designed with non-uniform structure where the inner and outer walls maintain smooth solid surfaces for strength and low friction, while the intermediate layer uses foamed material for weight reduction. This local differentiation of material properties resolves the contradiction between strength and weight.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The duct wall combines different material structures - solid thermoplastic for inner/outer walls and foamed thermoplastic for the intermediate layer. This composite approach achieves both mechanical strength (from solid surfaces) and weight reduction (from foamed core).

Inventive Principle:

Principle #40Composite materials

2Strength

If solid thermoplastic material is used for cable protection tubes, then mechanical strength is improved, but production costs increase

Engineering Contradiction:

Improvemechanical strengthVSAvoidproduction costs

Core Design Contradiction:

StrengthVSEase of manufacture

Solution Approach 1:

The duct wall is designed with non-uniform structure where the inner and outer walls maintain smooth solid surfaces for strength and low friction, while the intermediate layer uses foamed material for weight reduction. This local differentiation of material properties resolves the contradiction between strength and weight.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The duct wall combines different material structures - solid thermoplastic for inner/outer walls and foamed thermoplastic for the intermediate layer. This composite approach achieves both mechanical strength (from solid surfaces) and weight reduction (from foamed core).

Inventive Principle:

Principle #40Composite materials

3Ease of operation

If the duct inner wall has a smooth surface, then friction for cable routing is reduced, but structural stability may be compromised

Engineering Contradiction:

Improvefriction for cable routingVSAvoidstructural stability

Core Design Contradiction:

Ease of operationVSStability of the object's composition

Solution Approach 1:

The duct wall is designed with non-uniform structure where the inner and outer walls maintain smooth solid surfaces for strength and low friction, while the intermediate layer uses foamed material for weight reduction. This local differentiation of material properties resolves the contradiction between strength and weight.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The duct wall combines different material structures - solid thermoplastic for inner/outer walls and foamed thermoplastic for the intermediate layer. This composite approach achieves both mechanical strength (from solid surfaces) and weight reduction (from foamed core).

Inventive Principle:

Principle #40Composite materials

4Weight of moving object

If the duct wall has a three-layer structure with foamed intermediate layer, then weight is reduced, but manufacturing complexity increases

Engineering Contradiction:

ImproveweightVSAvoidmanufacturing complexity

Core Design Contradiction:

Weight of moving objectVSDevice complexity

Solution Approach 1:

The duct wall is designed with non-uniform structure where the inner and outer walls maintain smooth solid surfaces for strength and low friction, while the intermediate layer uses foamed material for weight reduction. This local differentiation of material properties resolves the contradiction between strength and weight.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The duct wall combines different material structures - solid thermoplastic for inner/outer walls and foamed thermoplastic for the intermediate layer. This composite approach achieves both mechanical strength (from solid surfaces) and weight reduction (from foamed core).

Inventive Principle:

Principle #40Composite materials

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 achieves a weight reduction of at least 20% with comparable mechanical properties to solid ducts, ensuring low friction for cable insertion and resistance to internal pressures over 10 bar, while reducing production and transportation costs.

Implementation Method 1

the duct wall also having an at least three-layer structure consisting of a foamed intermediate layer

Methodology Applied

Scientific EffectFoaming: Foam

Data Source

PatentEP2477289B1Cable conduit

Publication Date: 2017.03.15 DR ERNST VOGELSANG

AI summary

The cable conduit made of thermoplastic material has a channel wall (2) of circular cross-section enclosed with a cable guide channel (3) with channel inner wall (4) and channel outer wall (5). The channel wall has a three-layer structure composed of foamed intermediate layer (7), smooth-surfaced channel inner wall and channel outer wall. The foamed intermediate layer is axially inserted in comparison to stabilizing layer (8). The stabilizing layer of circular cross section is arranged concentrically to common center (M) in comparison to channel inner wall and outer wall.