Tire Tread Bend Groove Layout for Wet Grip and Steering Stability

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Tires face a trade-off between improved wet performance and compromised steering stability and wear resistance due to the arrangement of grooves and sipes, which affects their performance on both wet roads and snowy conditions.

Innovation Solution

A tire design featuring a tread portion with specific circumferential grooves, bend grooves, auxiliary grooves, and sipes that optimize the drainage of water while maintaining structural integrity and wear resistance, including a first middle land region with bend grooves having distinct bent angles and auxiliary grooves that enhance steering stability and snow performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If grooves and sipes are increased in the land regions to improve wet performance, then wet performance is improved, but steering stability and wear resistance are deteriorated

Engineering Contradiction:
Improvewet performanceVSAvoidsteering stability
Core Design Contradiction:
ReliabilityVSStability of the object's composition

Solution Approach 1:

The tread portion is divided into multiple land regions (shoulder land region, middle land region, crown land region) with different groove arrangements. Each region is segmented to perform specific functions: shoulder regions handle wet drainage, middle regions maintain steering stability, and crown regions provide wear resistance. This segmentation allows wet performance improvement without compromising overall stability.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Different groove configurations are applied to different local regions of the tread. The shoulder land region has circumferential grooves for wet drainage, while the middle land region has bend grooves with specific bent angles (θ1 > θ2) to maintain structural integrity. This local differentiation enables each region to optimize its performance characteristics.

Inventive Principle:
Principle #3Local quality

2Reliability

If grooves and sipes are increased in the land regions to improve wet performance, then wet performance is improved, but wear resistance is deteriorated

Engineering Contradiction:
Improvewet performanceVSAvoidwear resistance
Core Design Contradiction:
ReliabilityVSDuration of action of stationary object

Solution Approach 1:

The tread is segmented into regions with different groove densities. The crown land region and middle land region have fewer and more strategically placed grooves compared to the shoulder regions, preserving rubber material in high-wear areas while maintaining wet drainage capability in less critical regions.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Groove depth, width, and pattern vary by location. Crown and middle regions have shallower, fewer grooves to preserve wear resistance, while shoulder regions have deeper grooves optimized for water evacuation. The bend grooves in the middle region have asymmetric bent angles that balance drainage with structural strength.

Inventive Principle:
Principle #3Local quality

3Reliability

If bend grooves with asymmetric bent angles are provided in the middle land region, then wet performance is improved while steering stability is maintained, but device complexity increases

Engineering Contradiction:
Improvewet performanceVSAvoidtread pattern complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The bend grooves feature asymmetric bent angles where θ1 (first bent portion) is greater than θ2 (second bent portion). This asymmetry creates optimized water flow paths while maintaining structural integrity. The specific angular relationship enhances wet performance without requiring complex additional components.

Inventive Principle:
Principle #4Asymmetry

Solution Approach 2:

The bend grooves with asymmetric angles serve multiple functions simultaneously: they drain water from the tread, maintain steering stability through their structural configuration, and contribute to wear resistance by distributing stress. This multi-functionality reduces the need for separate features, managing overall complexity.

Inventive Principle:
Principle #6Universality (Multi-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

The tire achieves improved wet performance, maintains steering stability, and exhibits excellent wear resistance and snow performance by effectively draining water and forming hard snow blocks, as demonstrated through experimental results.

Implementation Method 1

the bend grooves each comprise a first portion extending from the first end to a bent point of the first bent portion, a second portion extending from the bent point of the first bent portion to a bent point of the second bent portion, and a third portion extending from the bent point of the second bent portion to the second end

Methodology Applied
Scientific EffectGravity: Gravitation

Data Source

PatentEP4101658B1tire
Publication Date: 2024.02.14 SUMITOMO RUBBER INDUSTRIES LTD
  • EP4101658B1 patent drawingFigure 1
  • EP4101658B1 patent drawingFigure 2
  • EP4101658B1 patent drawingFigure 3

AI summary

A tire has a tread portion 2. The first middle land region 11 is provided with bend grooves 15 each having a first end 15a and a second end 15b. The first end 15a is connected to the first shoulder circumferential groove 5. The second end 15b is connected to one of the bend grooves 15 next in one of two opposite circumferential directions. Each bend groove 15 has two bent portions 16 and 17 at which the groove is bent. The bent angle θ1 at the first bent portion 16 is greater than the bent angle 02 at the second bent portion 17.