Asymmetric Tyre Tread with Partial Lateral Grooves for Snow and Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
All-season tires face a trade-off between steering stability on dry road conditions and on-snow performance, as features that enhance snow traction, such as lateral grooves and sipes, compromise pattern rigidity and thereby deteriorate steering stability.
Innovation Solution
The tire design incorporates an asymmetric tread pattern with specific longitudinal edges, middle land portions, and lateral grooves that terminate within the land portions, along with sipes and chamfered corners, to maintain rigidity and improve traction on snow while maintaining steering stability on dry roads.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If lateral grooves and sipes are provided on the tread portion to improve on-snow performance, then snow shearing force and ground scratching effect are enhanced, but pattern rigidity is reduced leading to deteriorated steering stability on dry road conditions
Solution Approach 1:
The tread portion is divided into multiple land portions (outboard middle land portion, inboard middle land portion, outboard shoulder land portion, inboard shoulder land portion) separated by grooves. This segmentation allows different regions to serve different functions: some areas provide snow shearing capability while others maintain rigidity for steering stability.
Solution Approach 2:
Different land portions have different groove configurations tailored to their specific functions. The outboard middle land portion has lateral grooves terminating within the land to balance snow performance and rigidity, while the shoulder land portions have lateral grooves extending to the tread edge for enhanced snow traction. Sipes are strategically placed in specific regions to optimize both snow shearing and pattern rigidity.
2Reliability
If a large number of long lateral grooves are provided on the tread portion to improve on-snow performance, then snow shearing force is enhanced, but pattern rigidity is reduced
Solution Approach 1:
The lateral grooves in the outboard middle land portion extend only partially across the land portion width, terminating within the land rather than spanning the entire width. This partial action provides sufficient snow shearing capability while preserving adequate pattern rigidity, avoiding the excessive reduction that would occur with full-width grooves.
Solution Approach 2:
The groove system is segmented into different types and locations: outboard middle lateral grooves, inboard middle lateral grooves, outboard shoulder lateral grooves, and inboard shoulder lateral grooves. Each segment is optimized for its specific location, allowing the overall pattern to achieve both snow performance and rigidity through distributed functionality.
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
This design enhances both on-snow performance by generating powerful snow-shearing force and maintains excellent steering stability on dry roads by suppressing excessive reduction in rigidity, as demonstrated through comparative testing.
Implementation Method 1
Snow shearing force is generated by being compressed snow on the ground and then shearing it
Implementation Method 2
edges of lateral grooves and sipes can improve traction by scratching compressed snow surface of the ground
Data Source
AI summary
A tyre includes a tread portion including an outboard middle land portion disposed between an outboard tread edge and a tyre equator. The outboard middle land portion includes first and second longitudinal edges, outboard middle lateral grooves extending from the first longitudinal edge and having terminal ends within the outboard middle land portion, first outboard middle sipes extending from the respective terminal ends of the outboard middle lateral grooves to the second longitudinal edge, and second outboard middle sipes extending from the first longitudinal edge toward the second longitudinal edge beyond the terminal ends of the outboard middle lateral grooves and terminating within the outboard middle land portion. The outboard middle land portion is not provided with any lateral grooves that extend from the second longitudinal edge toward the first longitudinal edge to reach an axial center location of the outboard middle land portion.