Tread Sipe Layout for Ice Grip and Dry Steering Stability

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing tires struggle to achieve excellent performance on ice and snow while maintaining steering stability on dry road surfaces.

Innovation Solution

A tire design featuring a tread portion with specific configurations, including zigzag shoulder sipes, overlapping middle sipe groups, and strategically placed grooves, which enhance rigidity and friction on both axial and circumferential directions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the tread pattern includes many sipes and grooves to improve ice and snow performance, then traction on ice and snow is improved, but steering stability on dry road surface deteriorates

Engineering Contradiction:
Improvetraction performance on ice and snowVSAvoidsteering stability on dry road surface
Core Design Contradiction:
ReliabilityVSStability of the object's composition

Solution Approach 1:

The patent applies local quality by creating different sipe configurations in different regions of the tread. The shoulder land portions have sipes extending in the tire axial direction to improve ice and snow traction, while the center land portion has sipes extending in the tire circumferential direction to maintain steering stability on dry surfaces. This regional differentiation allows each area to optimize for its specific functional requirements.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The tread pattern is segmented into distinct functional zones: shoulder land portions with axial sipes for snow/ice grip, center land portion with circumferential sipes for directional stability, and intermediate transition zones. This segmentation allows independent optimization of each region's sipe characteristics without compromising overall performance.

Inventive Principle:
Principle #1Segmentation

2Reliability

If sipes are made long to increase friction on ice and snow, then traction is improved, but rigidity of the land portion decreases

Engineering Contradiction:
Improvefriction on ice and snowVSAvoidrigidity of land portion
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The patent implements local quality by varying sipe length according to location. Shoulder sipes extend the full axial width of the shoulder land portion to maximize friction on snow and ice, while center sipes are shorter and arranged to maintain land portion rigidity. This localized differentiation resolves the contradiction between friction enhancement and structural strength.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The sipe configuration dynamically adapts to different operating conditions through its geometric design. Long axial sipes in the shoulder regions activate during snow/ice contact to provide friction, while the overall land portion geometry maintains sufficient rigidity for steering control on various surfaces.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentEP4393725B1tire
Publication Date: 2025.12.31 SUMITOMO RUBBER INDUSTRIES LTD
  • EP4393725B1 patent drawingFigure 1
  • EP4393725B1 patent drawingFigure 2
  • EP4393725B1 patent drawingFigure 3

AI summary

Provided is a tire that can exhibit excellent performance on ice and snow while maintaining steering stability on a dry road surface. The tire has a tread portion 2. The tread portion 2 includes: first and second tread ends T1 and T2; a plurality of circumferential grooves 3; and a plurality of land portions 4. A first shoulder land portion 11 is provided with a plurality of shoulder sipes 30 each having a length that is not less than 60% of a width in a tire axial direction of the first shoulder land portion 11. A first middle land portion 13 is provided with a plurality of middle sipe groups 38 arranged in a tire circumferential direction. Each of the middle sipe groups 38 is formed such that a plurality of closed sipes 39 thereof overlap with each other in both the tire axial direction and the tire circumferential direction.