Excess-Length Yarn Rope Structure for Cut Resistance Under Tension

Solution Overview

Problem

Existing textile fiber ropes suffer from decreased cut resistance when under tension, which is a critical issue in applications like mountain climbing where ropes are frequently subjected to sharp edges and dynamic loads.

Innovation Solution

A rope design featuring a core and a sheath with an intermediate sheath or reinforcement comprising a thread with excess length, where the first thread is significantly longer than the second thread, ensuring that the first thread remains tension-free even when the rope is stretched, thereby maintaining high cut resistance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If high-strength fibers are used to increase cut resistance, then cut resistance is improved, but elongation capability deteriorates

Engineering Contradiction:

Improvecut resistanceVSAvoidelongation capability

Core Design Contradiction:

StrengthVSStability of the object's composition

Solution Approach 1:

The rope is divided into two functional segments: a core made of high-strength fibers for cut resistance and an outer sheath made of elastic fibers for elongation capability. This segmentation allows each segment to perform its specialized function without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The rope uses a composite structure combining two different fiber types with complementary properties: high-strength fibers (aramid, UHMWPE) for cut resistance and elastic fibers (polyamide, polyester) for energy absorption through elongation. The composite design synergistically combines the advantages of both material types.

Inventive Principle:

Principle #40Composite materials

2Stability of the object's composition

If conventional fibers are used to maintain elongation capability, then energy absorption is improved, but cut resistance deteriorates

Engineering Contradiction:

Improveelongation capabilityVSAvoidcut resistance

Core Design Contradiction:

Stability of the object's compositionVSStrength

Solution Approach 1:

The rope is divided into two functional segments: a core made of high-strength fibers for cut resistance and an outer sheath made of elastic fibers for elongation capability. This segmentation allows each segment to perform its specialized function without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The rope uses a composite structure combining two different fiber types with complementary properties: high-strength fibers (aramid, UHMWPE) for cut resistance and elastic fibers (polyamide, polyester) for energy absorption through elongation. The composite design synergistically combines the advantages of both material types.

Inventive Principle:

Principle #40Composite materials

3Adaptability or versatility

If the rope is under tension during cutting operations, then real-world applicability is improved, but cut resistance deteriorates

Engineering Contradiction:

Improvereal-world applicabilityVSAvoidcut resistance

Core Design Contradiction:

Adaptability or versatilityVSStrength

Solution Approach 1:

The rope structure dynamically adapts to loading conditions: under tension, the elastic sheath stretches to absorb energy while the high-strength core maintains structural integrity and cut resistance. The dynamic interaction between the two layers ensures optimal performance during fall arrest and cutting operations under load.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The rope uses a composite structure combining two different fiber types with complementary properties: high-strength fibers (aramid, UHMWPE) for cut resistance and elastic fibers (polyamide, polyester) for energy absorption through elongation. The composite design synergistically combines the advantages of both material types.

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 rope exhibits increased cut resistance under tension, reducing the risk of injury from wire breaks and enhancing its suitability for mountain ropes, lanyards, and winch ropes by maintaining energy absorption capabilities.

Implementation Method 1

the excess-length yarn is formed by comprising at least a first yarn and a second yarn which are twisted together

Methodology Applied

Scientific EffectTwisting:

Implementation Method 2

fibers, as mentioned in the introduction, exhibit lower cut resistance under tension. However, with the extra-long yarn, some fibers can remain in a tension-free state even when the rope is under tension

Methodology Applied

Scientific EffectTension-free state advantage:

Data Source

PatentEP3967799B1Textile fibre rope comprising a plied yarn or core-sheath yarn and method of manufacturung such a yarn

Publication Date: 2024.11.06 TEUFELBERGER FIBER ROPE

Figure 1
Figure 2~3
Figure 4

AI summary

The invention relates to a rope (1) made of textile fiber material, comprising a rope core (2) and a sheath (3) surrounding the rope core (2), wherein the sheath (3), an intermediate sheath (4) located between the sheath (3) and the rope core (2), and/or a reinforcement located between the sheath (3) and the rope core (2) comprise a yarn (6) with excess length (Δ), wherein the yarn (6) with excess length (Δ) is formed by comprising at least a first yarn (7) and a second yarn (8) which are twisted together, the first yarn (7) having a greater length than the second yarn (8), measured in an untwisted state of a unit length of the yarn (6). In a further aspect, the invention relates to a method for producing a yarn (6) with excess length (Δ) for the aforementioned rope (1).