Tire Imbalance Correction Using Black Coated Layer

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Solution Overview

Problem

Existing methods for correcting tire imbalance either fail to address the imbalance in the tire itself, leading to recurring issues, or use sponge materials that may separate and detract from the tire's appearance and commercial value.

Innovation Solution

A black coated layer formed on the inner surface of the tire using water-soluble paint containing carbon black is applied at the point of lightest weight, reducing weight imbalance without being easily recognizable, thus maintaining appearance and commercial value.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a sponge material weight member is adhered to the inner surface of the tire to correct imbalance, then the weight imbalance is reduced, but the weight member may separate during running and the tire appearance is deteriorated

Engineering Contradiction:
Improveimbalance correction effectivenessVSAvoidweight member separation and appearance deterioration
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent changes the material parameter from low-specific-gravity sponge material to high-specific-gravity black paint, thereby reducing the volume of the correction layer while maintaining the same weight correction effect. This resolves the separation issue and appearance problem by eliminating the need for bulky adhesive-mounted weight members.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent uses a composite approach by applying black paint (containing pigment and binder) to form a coated layer that serves both as a visual match to the tire inner surface and as a functional imbalance correction element, combining aesthetic and mechanical functions in one material layer.

Inventive Principle:
Principle #40Composite materials

2Object-affected harmful factors

If a black coated layer is formed on the inner surface of the tire to correct imbalance, then the appearance and commercial value are maintained, but the weight imbalance correction effectiveness must be ensured

Engineering Contradiction:
Improveappearance deteriorationVSAvoidimbalance correction effectiveness
Core Design Contradiction:
Object-affected harmful factorsVSReliability

Solution Approach 1:

The patent carefully controls the parameters of the black painted layer including its weight (3-10 grams), circumferential length (15-70 degrees), and specific gravity (1.00-1.10) to ensure both aesthetic invisibility and sufficient imbalance correction effectiveness.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The black coated layer is applied locally only at the circumferential position corresponding to the point of lightest weight, rather than uniformly across the entire inner surface, thereby providing imbalance correction while minimizing visual impact and material usage.

Inventive Principle:
Principle #3Local quality

3Reliability

If a weight member with low specific gravity is used, then the weight imbalance is corrected, but the volume becomes large and gives a bad impression

Engineering Contradiction:
Improveweight imbalance correctionVSAvoidweight member volume
Core Design Contradiction:
ReliabilityVSVolume of moving object

Solution Approach 1:

The patent changes the specific gravity parameter of the correction material from low (sponge material) to high (black paint with specific gravity 1.00-1.10), which dramatically reduces the volume required to achieve the same weight correction effect, eliminating the bulky appearance problem.

Inventive Principle:
Principle #35Parameter changes

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

The black coated layer effectively corrects tire weight imbalance without being noticeable, preventing deterioration in appearance and commercial value, while maintaining the correction's effectiveness without the risk of sponge material separation.

Implementation Method 1

a method of correcting imbalance of a tire, comprising a step of forming a black coated layer on the inner surface of the tire at the circumferential position of the point of lightest weight of the tire so that the weight imbalance of the tire is reduced

Methodology Applied
Scientific EffectDeposition: Deposition (physical)

Data Source

PatentEP3578394B1Tire imbalance correction method and tire
Publication Date: 2021.12.08 SUMITOMO RUBBER INDUSTRIES LTD
  • EP3578394B1 patent drawingFigure 1
  • EP3578394B1 patent drawingFigure 2

AI summary

A method of correcting imbalance of a tire (1) comprises a step of forming a coated layer on the inner surface of the tire at the point (P) of lightest weight of the tire so as to reduce the imbalance of the tire. The coated layer (10) has a black color substantially the same as the color of the inner surface so that it becomes difficult to recognize the correction of the weight imbalance.