Multi-Layer Tire Tread Structure for Wear-Stable Noise Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional tires experience an increase in vibration noise as the tread wears, leading to a deterioration in noise performance due to increased rigidity of the land part and reduced effectiveness in suppressing vibrations.
Innovation Solution
A tire design featuring four or more rubber layers with varying complex elastic moduli, where the difference between adjacent layers is 1.0 MPa or more, and the modulus decreases from the tread surface inward, combined with a larger groove area ratio in the shoulder land parts, and the inclusion of low-density members on the inner peripheral surface to absorb vibrations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a tread part is worn, then the rigidity of the land part increases, but the noise suppression effect decreases and vibration noise increases
Solution Approach 1:
The tread part is segmented into multiple rubber layers (four or more) with different complex elastic moduli. This segmentation allows each layer to contribute differently to vibration absorption, maintaining noise suppression effectiveness even as the tread wears and the overall structure becomes more rigid.
Solution Approach 2:
Different rubber layers are assigned different complex elastic moduli to create local quality variations. The layer closest to the road surface has a higher complex elastic modulus for durability, while inner layers have progressively lower moduli for vibration absorption, ensuring noise suppression is maintained throughout the tire's service life.
2Object-affected harmful factors
If multiple rubber layers with different complex elastic moduli are used, then noise performance is maintained after abrasion, but the device complexity increases
Solution Approach 1:
The tread part is constructed as a composite structure with four or more rubber layers, each having different complex elastic moduli. This composite material approach maintains noise performance after abrasion by preserving the vibration absorption characteristics of the softer inner layers even when the harder outer layers wear down.
Solution Approach 2:
The complex elastic modulus parameter is systematically varied across the rubber layers, with the difference between adjacent layers being 1.0 MPa or more. This parameter change strategy enables effective vibration absorption while providing clear manufacturing specifications that reduce complexity.
3Object-affected harmful factors
If the groove area ratio in the shoulder land part is made larger than in the center land part, then vibration noise is suppressed, but the manufacturing precision requirements increase
Solution Approach 1:
The tread pattern is designed with asymmetric groove area ratios, where the shoulder land parts have larger groove area ratios than the center land part. This asymmetry targets vibration noise suppression at the shoulder regions where contact patch dynamics differ from the center, providing effective noise control with straightforward manufacturing specifications.
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 design effectively maintains noise performance by absorbing and dissipating vibrations across multiple layers, reducing resonance and suppressing noise deterioration even after significant wear.
Implementation Method 1
four or more rubber layers each having a different complex elastic modulus
Implementation Method 2
absorbing and dissipating vibrations across multiple layers
Implementation Method 3
low-density members selected from the group consisting of a sealant layer, a noise suppressing body, and a three-dimensional reticulate structure
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An object of the present invention is to provide a tire in which deterioration of noise performance after abrasion is suppressed. The tire has a tread part (1) comprising four or more rubber layers each having a different complex elastic modulus at 30°C, wherein the tread part (10) has two or more circumferential grooves (11, 12, 13) extending continuously in a circumferential direction of the tire, a pair of shoulder land parts (16, 17) partitioned by the circumferential grooves (11, 12), and a center land part (18, 19) located between the pair of shoulder land parts (16, 17).