Pneumatic Tire Sipe Bottom Protrusions and Concave Portions

Solution Overview

Problem

Pneumatic tires with sipes on the tread portion face issues of excessive land portion collapse and impaired steering stability due to localized rigidity increases from protrusions, which affect driving performance on frozen road surfaces.

Innovation Solution

Incorporating concave portions between adjacent sipes, positioned close to the bottom protrusions, to maintain uniform land portion rigidity and enhance driving stability while preventing excessive collapse.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If bottom protrusions are provided at parts in the sipe longitudinal direction, then excessive collapse of land portions is prevented, but rigidity locally increases near the protrusions and steering stability is impaired

Engineering Contradiction:

Improveland portion collapse resistanceVSAvoidsteering stability

Core Design Contradiction:

StrengthVSStability of the object's composition

Solution Approach 1:

The patent applies local quality by providing bottom protrusions only at specific positions (heels and toes) of the sipes rather than uniformly across all sipes. This localized approach prevents excessive land portion collapse at critical areas while avoiding uniform rigidity increases that would impair steering stability. The selective placement creates different mechanical properties in different locations to optimize both collapse resistance and steering performance.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent segments the sipe structure by dividing it into multiple components: the sipe groove itself, bottom protrusions at specific locations (heels and toes), and land portions between sipes. This segmentation allows independent optimization of each component - the protrusions provide collapse resistance where needed while the spaced arrangement maintains overall land portion flexibility for steering stability.

Inventive Principle:

Principle #1Segmentation

2Reliability

If sipes are formed in the tread portion to improve driving performance on frozen road surfaces, then edge effect is exerted for excellent driving performance, but rigidity of land portions decreases and excessive collapse occurs

Engineering Contradiction:

Improvedriving performance on frozen roadVSAvoidland portion rigidity

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The patent applies local quality by providing bottom protrusions only at specific positions (heels and toes) of the sipes rather than uniformly across all sipes. This localized approach prevents excessive land portion collapse at critical areas while avoiding uniform rigidity increases that would impair steering stability. The selective placement creates different mechanical properties in different locations to optimize both collapse resistance and steering performance.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent converts the potential harm of land portion collapse into a benefit by strategically placing bottom protrusions that prevent collapse only where needed. The protrusions transform the weak point (land portion between sipes) into a strengthened area at critical locations, turning the structural vulnerability created by sipe formation into an optimized design that maintains both flexibility and strength.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

Data Source

PatentUS11427036B2Pneumatic tire

Publication Date: 2022.08.30 TOYO TIRE CORP

AI summary

A pneumatic tire according to the embodiment includes a land portion 20 provided on a tread portion, a plurality of sipes 30 provided on the land portion 20, and at least one concave portion 34 disposed between two adjacent sipes 30. Each of the sipes 30 has, at parts in a sipe longitudinal direction, bottom protrusions 42, 44, 46 protruding from a bottom surface of the sipe 30 toward a tread surface. The concave portion 34 is provided close to the bottom protrusions 42, 44, 46.