Pneumatic Tire Tread with Segmented Sipe Design for Ice and Dry Balance

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional studless tires face challenges in balancing performance on ice and snow roads with dry roads, as increasing sipe density improves ice performance but deteriorates dry road wear resistance and block rigidity, leading to reduced traction and shorter tire life.

Innovation Solution

The tire design features a larger sipe interval to increase block rigidity, a smaller pitch length to enhance edge effect, and a foamed rubber tread with a specific elastic modulus to improve ground contact area and wear resistance, while maintaining on-ice performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the number of sipes formed in the land portion block is increased, then the on-ice performance is improved, but the block rigidity is deteriorated

Engineering Contradiction:
Improveon-ice performanceVSAvoidblock rigidity
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The patent applies local quality by differentiating the treatment of sipes across different regions of the land portion block. Specifically, sipes are formed in the first land portion block but omitted in the second land portion block, creating localized variations in edge effect while preserving block rigidity in critical areas. This regional differentiation allows the tire to achieve on-ice performance where needed without compromising overall structural integrity.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent segments the land portion into multiple blocks (first land portion block and second land portion block) with different sipe configurations. By dividing the continuous land portion into discrete segments with varying sipe densities, the design achieves a balance between edge effect generation and rigidity maintenance, preventing the uniform sipe formation that would compromise overall block stiffness.

Inventive Principle:
Principle #1Segmentation

2Reliability

If the number of sipes formed in the land portion block is increased, then the braking performance on ice road surface is improved, but the wear resistant performance on dry road surface is deteriorated

Engineering Contradiction:
Improvebraking performance on iceVSAvoidwear resistant performance
Core Design Contradiction:
ReliabilityVSDuration of action of stationary object

Solution Approach 1:

The patent implements local quality by selectively forming sipes only in the first land portion block while omitting them in the second land portion block. This localized approach concentrates the edge effect benefits for ice braking performance in specific regions while preserving wear-resistant continuous rubber surfaces in other regions, thereby maintaining dry road wear resistance.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

By segmenting the land portion into multiple blocks with different sipe configurations, the patent creates a heterogeneous tread structure where some segments optimize for ice braking while others optimize for wear resistance, achieving a balance between these competing performance requirements.

Inventive Principle:
Principle #1Segmentation

3Strength

If the pitch length is made long, then the block rigidity is increased, but the number of land portion blocks within ground contact length is decreased

Engineering Contradiction:
Improveblock rigidityVSAvoidnumber of land portion blocks
Core Design Contradiction:
StrengthVSProductivity

Solution Approach 1:

The patent applies local quality by creating heterogeneity in land portion block characteristics. By having the first land portion block with sipes and the second without, the design optimizes local edge effect generation while maintaining overall rigidity through the presence of multiple distinct blocks within the ground contact length, preventing the monotony that would result from uniform long-pitch design.

Inventive Principle:
Principle #3Local quality

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 configuration achieves high braking performance on ice, improved wear resistance on dry roads, and extended tire life by balancing block rigidity and edge effect, ensuring effective traction on various surfaces.

Implementation Method 1

by increasing the number of the sipes formed in the land portion block, an edge component that scratches the road surface can be increased, and therefore braking performance on the ice and snow road

Methodology Applied
Scientific EffectFriction: Friction

Implementation Method 2

a foamed rubber tread with a specific elastic modulus to improve ground contact area and wear resistance

Methodology Applied
Scientific EffectElasticity: Elasticity

Data Source

PatentEP3375640B1tire
Publication Date: 2020.10.07 BRIDGESTONE CORP
  • EP3375640B1 patent drawingFigure 1
  • EP3375640B1 patent drawingFigure 2
  • EP3375640B1 patent drawingFigure 3

AI summary

In a pneumatic tire 10 according to the present invention, as an average block edge component Dball is defined by an average of edge components of all blocks against a tire circumferential direction, an average sipe edge component Dsall is defined by an average of edge components of all sipes against the tire circumferential direction and an average block rigidity G is defined by an average of the rigidity of all blocks, a relation of 2.20 (mm)3/N ≤ (Dball/Dsall)/G ≤ 4.00 (mm)3/N is fulfilled.