Tyre Tread Diagonal Notch Design for Wear and Rolling Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current heavy-duty tires face issues with wear regularity and rolling resistance, particularly with oblique cutouts on the tread that can lead to irregular wear patterns and increased fuel consumption due to inefficient rolling resistance.
Innovation Solution
A tire design featuring a radial carcass reinforcement with a crown reinforcement comprising two working layers, a layer of circumferential reinforcing elements, and oblique cutouts with specific depth and width ratios, along with calendering layers having lower elastic moduli and loss factors, to improve wear regularity and reduce rolling resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If oblique cutouts are introduced on the tread to improve rolling resistance and fuel efficiency, then energy consumption is reduced, but wear regularity deteriorates due to irregular wear patterns
Solution Approach 1:
The patent applies local quality by varying the depth of oblique cutouts across different regions of the tread. The cutouts have different depths in different zones, allowing each region to contribute differently to rolling resistance reduction while maintaining overall wear uniformity. This localized variation prevents the irregular wear patterns that would result from uniform cutout depths.
Solution Approach 2:
The patent employs asymmetry in the design of oblique cutouts, where the cutouts are not symmetrically distributed or uniformly sized across the tread surface. This asymmetric configuration creates a more uniform stress distribution during tire rotation and loading, preventing localized wear concentration and maintaining wear regularity while still achieving fuel efficiency improvements.
2Reliability
If the elastic modulus of calendering layers is reduced to control deformations and improve wear regularity, then wear uniformity is improved, but rolling resistance increases
Solution Approach 1:
The patent applies parameter changes by carefully selecting and optimizing the elastic modulus of calendering layers to specific ranges. Rather than simply reducing the modulus, the patent identifies optimal modulus values that balance deformation control with energy loss. This parameter optimization allows the tire to maintain wear regularity while minimizing the increase in rolling resistance that would result from excessive softening of the calendering layers.
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 enhances wear regularity and reduces rolling resistance, leading to improved fuel efficiency and extended tire life by controlling deformations and maintaining satisfactory cohesion and endurance properties.
Implementation Method 1
the tensile modulus of elasticity at 10% elongation of at least one calendering layer of at least one top working layer being less than 8.5 MPa and the maximum value of tan(δ), denoted tan(δ)max, of said at least one calendering layer of at least one top working layer being less than 0.100
Implementation Method 2
the maximum value of tan(δ), denoted tan(δ)max, of said at least one calendering layer of at least one top working layer being less than 0.100
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a tyre comprising a crown reinforcement formed by at least two working crown layers (41, 43) of reinforcing elements and at least one layer (42) of circumferential reinforcing elements. According to the invention, the tread includes at least one diagonal notch (7), the depth of said at least one diagonal notch, measured on a new tyre, being greater than or equal to 40% of the thickness of the tread, and the ratio of the width of said at least one diagonal notch measured at the base thereof to the width of same measured at the surface of the tread is greater than 1.2. The tensile modulus of elasticity at 10% elongation of at least one skim coat of at least one working crown layer is less than 8.5 MPa, and the maximum tan(δ) value, denoted tan(δ)max, of the at least one skim coat of at least one working crown layer is less than 0.100. Fig. 2.