Pneumatic Tire Wear Indicator Segmentation for Crack Resistance

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing pneumatic vehicle tire wear indicators lack stability against crack formation and do not effectively indicate safety-relevant wear conditions, particularly in relation to the increased risk of aquaplaning due to reduced water drainage capacity at tread depths between 3 mm to 4 mm.

Innovation Solution

The wear indicator is designed with Y-shaped indicator parts, where the radially innermost part forms a stable basis, and the outer parts are connected to the groove flank at two points, with gradually increasing surface size from outer to inner, ensuring stability and preventing rubber tearing, and are positioned at specific heights to indicate legal minimum tread depth.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If wear indicators are designed with simple geometric shapes, then manufacturing is easier, but stability against crack formation deteriorates

Engineering Contradiction:
Improveease of manufactureVSAvoidstability against crack formation
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The wear indicator is divided into multiple indicator parts (first, second, and third indicator parts) with different heights, where each part serves a specific function. The third indicator part forms a stable base connected to the groove flank, while the first and second indicator parts provide visual wear indication at different stages. This segmentation allows the base to provide structural stability while the indicator parts remain simple for manufacturing.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The indicator parts are arranged at different heights in the radial direction, creating a multi-level structure. The third indicator part is at the lowest height forming a stable base, the second indicator part is at an intermediate height, and the first indicator part is at the highest height. This vertical arrangement provides stability through the base while maintaining simple geometric shapes for easy manufacturing.

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

2Illumination intensity

If wear indicators have large indicator surfaces, then visibility is improved, but water drainage capacity deteriorates

Engineering Contradiction:
ImprovevisibilityVSAvoidwater drainage capacity
Core Design Contradiction:
Illumination intensityVSObject-generated harmful factors

Solution Approach 1:

The wear indicator is segmented into multiple parts at different heights with progressively smaller indicator surfaces. The third indicator part (base) has the largest surface area for stability, the second indicator part has an intermediate surface area, and the first indicator part has the smallest surface area. This segmentation allows adequate visibility while minimizing the total area that could impede water drainage.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Different parts of the wear indicator have different surface areas tailored to their specific functions. The third indicator part has a larger surface area to provide a stable base, while the first and second indicator parts have smaller surface areas to maintain visibility without significantly impacting water drainage. This local differentiation optimizes both visibility and drainage performance.

Inventive Principle:
Principle #3Local quality

3Loss of information

If indicator parts are arranged one above another in step-like manner, then wear stages are clearly indicated, but crack formation risk increases

Engineering Contradiction:
Improvewear stage indicationVSAvoidcrack formation resistance
Core Design Contradiction:
Loss of informationVSReliability

Solution Approach 1:

The wear indicator is segmented into three distinct indicator parts at different heights, where the third indicator part forms a stable base connected to the groove flank, and the first and second indicator parts are positioned on top of it. This segmentation creates clear visual differentiation of wear stages while the connected base structure prevents crack formation by providing continuous structural support.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The indicator parts are arranged vertically at different heights in the radial direction rather than horizontally, creating a step-like structure that clearly indicates different wear stages. The third indicator part at the lowest height provides a stable base, while the first and second indicator parts at higher heights provide visual indication without creating weak points that would lead to cracking.

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

Data Source

PatentEP3015291B1Pneumatic tyres for a vehicle
Publication Date: 2017.12.06 CONTINENTAL REIFEN DEUTSCHLAND GMBH
  • EP3015291B1 patent drawingFigure 1
  • EP3015291B1 patent drawingFigure 2~3

AI summary

Vehicle pneumatic tire with a tread having at least one wear indicator (5) which is positioned in a circumferential groove (1) bounded by a groove base (2) and two groove flanks (3, 3'), wherein the wear indicator (5) has three indicator parts (6, 7, 8) which have indicator surfaces (6a, 7a, 8a) located at different heights (h, h2, h3) from the groove base (2) in a radial direction and running substantially parallel to the tread surface. The radially innermost indicator part (8) has the largest and the radially outermost indicator part (6) the smallest indicator surface (6a, 7a, 8a), wherein at least the radially innermost indicator part (8) is connected to a groove flank (3) and is plate-shaped, and wherein on the indicator surface (8a) of the radially innermost indicator part (8) the two further indicator parts (6, 7) are positioned one above the other, the outer one centered on the inner one.