Multi-Strand Cord Helical Geometry for Tire Durability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Construction plant vehicle tires face issues of perforation and cord breakages due to obstacles, leading to reduced tire life, as existing cords are either too stiff or have low elongation and energy-at-break, making them prone to damage under deformation and load.
Innovation Solution
A multi-strand cord with a 1×N structure, featuring a single layer of N strands wound in a helix with metal filaments, exhibiting a total elongation greater than 8.10% and an energy-at-break indicator exceeding 52 MJ/m³, designed to deform under stress and absorb load effectively, reducing stiffness and increasing durability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the cord is made stiffer to reinforce the tyre against obstacles, then the resistance to deformation improves, but the cord becomes more prone to breakage and perforation
Solution Approach 1:
The patent changes the mechanical parameters of the cord by optimizing the helical winding geometry (pitch, diameter, handedness) to achieve a specific stiffness range (3-15 GPa). This parameter optimization allows the cord to be flexible enough to deform over obstacles without breaking, while still providing sufficient reinforcement to protect the tyre structure.
Solution Approach 2:
The cord's dynamic response is optimized through its helical structure, which allows it to adapt its stiffness during deformation. When the tyre encounters an obstacle, the cord can dynamically deform and then return to its original shape, providing both flexibility during impact and structural reinforcement during normal operation.
2Reliability
If the cord has high total elongation to reduce breakage, then the ability to deform without breaking improves, but the force at break may be reduced
Solution Approach 1:
The cord is constructed as a composite structure with multiple metal filaments (3-19 filaments per strand, 2-6 strands) arranged in helical patterns. This composite architecture allows the cord to achieve both high elongation (6-12%) and high force at break (500-2000 N) by distributing stress across multiple filaments and optimizing their spatial arrangement.
3Ease of manufacture
If the cord structure is simplified to reduce manufacturing complexity, then the manufacturing cost decreases, but the performance in terms of elongation and energy at break may be compromised
Solution Approach 1:
The cord is segmented into multiple independent metal filaments (3-19 per strand) that are individually wound into helical strands (2-6 strands per cord). This segmentation allows each filament to deform independently, absorbing energy and preventing catastrophic failure. The segmented structure also simplifies manufacturing by allowing filaments to be processed and assembled separately before final cord formation.
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 cord significantly reduces the risk of perforation and breakage, extending tire life by hugging obstacles and distributing load, while its high elongation and energy-at-break characteristics enhance its ability to withstand deformation and stress without failing.
Implementation Method 1
the cord has a total elongation At>8.10% determined by the standard ASTM D2969-04 from 2014; and the energy-at-break indicator Er of the cord, defined by Er=∫0Atσ(Ai)×dAi where σ(Ai) is the tensile stress in MPa measured at the elongation Ai
Data Source
AI summary
A multi-strand cord (50) having a 1×N structure comprises a single layer (52) of N strands (54) wound in a helix about a main axis (A), each strand (54) having one layer (56) of metal filaments (F1) and comprising M>1 metal filaments wound in a helix about an axis (B). The cord (50) has a total elongation At>8.10% and the energy-at-break indicator Er of the cord (50), defined by Er=∫0Atσ(Ai)×dAi where σ(Ai) is the tensile stress in MPa measured at the elongation Ai and dAi is the elongation such that Er is strictly greater than 52 MJ/m3.