Handlebar-Shaped Truck Tire Sipe for Crack-Resistant Rigidity

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing sipes in heavy truck tires, particularly those with teardrop shapes, cause irregular wear, increased rolling resistance, and cracking due to stress concentration, compromising both rigidity and end-of-life traction.

Innovation Solution

A sipe design with a teardrop geometry where the middle section is positioned farther from the upper surface than the ends, featuring transitions that minimize crack propagation while maintaining rigidity and end-of-life traction.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the teardrop size is increased to prevent cracking at the bottom, then end of service traction is improved, but rigidity in the tread block decreases and rolling resistance increases

Engineering Contradiction:
Improvecrack preventionVSAvoidtread block rigidity
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The sipe features a teardrop-shaped void with non-uniform depth: deeper at the middle section (farther from upper surface) and shallower at the ends (closer to upper surface). This local variation in void depth provides crack prevention at the critical middle section while maintaining rigidity at the end sections, resolving the contradiction between reliability and strength.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The invention transitions from a traditional uniform-depth sipe to a three-dimensional teardrop-shaped void with varying depth throughout. By introducing depth variation as an additional dimensional parameter, the design achieves crack prevention without sacrificing overall tread block rigidity, as the shallower ends maintain structural integrity while the deeper middle prevents cracking.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Strength

If the teardrop is moved closer to the upper surface to maintain rigidity, then tread block strength is preserved, but end of service traction decreases

Engineering Contradiction:
Improvetread block rigidityVSAvoidend of service traction
Core Design Contradiction:
StrengthVSReliability

Solution Approach 1:

The teardrop-shaped void concentrates its depth variation at the middle section rather than uniformly reducing depth. This allows the middle section to provide end-of-service traction benefits while the overall sipe structure maintains adequate rigidity, resolving the contradiction between strength and reliability.

Inventive Principle:
Principle #3Local quality

3Reliability

If sipes are added to improve traction, then stopping distance and breakaway traction are improved, but irregular wear and rolling resistance increase

Engineering Contradiction:
Improvetraction performanceVSAvoidrolling resistance
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The teardrop-shaped sipe concentrates void volume at the middle section where it provides traction benefits, while the shallower ends maintain better contact with the road surface. This localized void distribution improves traction performance while minimizing the overall impact on rolling resistance and wear characteristics.

Inventive Principle:
Principle #3Local quality

Data Source

PatentEP4351889B1Tire sipe for heavy truck tread having handlebar shape
Publication Date: 2025.09.24 MICHELIN & CO (CIE GEN DES ESTAB MICHELIN)
  • EP4351889B1 patent drawingFigure 1
  • EP4351889B1 patent drawingFigure 2~3
  • EP4351889B1 patent drawingFigure 4

AI summary

A heavy truck tire tread that has a rib is provided. A sipe is in the rib that extends from a first lateral surface to a second lateral surface. A first end of a teardrop is located at the first lateral surface, and a second end at the second lateral surface. A middle section of the teardrop is located between the first and second ends in the lateral direction. A first transition is located between the first end and the middle section, and a second transition is located between the second end and the middle section and they both extend in the lateral and thickness directions. The entire middle section is farther from the upper surface in the thickness direction than any portion of the first or second ends are to the upper surface in the thickness direction.