Pneumatic Tire Asymmetric Side Reinforcement for Pinch Cut Resistance

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Pneumatic tires used on poorly maintained roads face increased resistance to external damage, such as pinch cuts, while also requiring weight reduction to minimize rolling resistance and environmental impact, which is challenging with existing methods that increase tire weight by adding more carcass plies.

Innovation Solution

A pneumatic tire design featuring a carcass with a folded-up portion, a belt layer, and a side reinforcement layer made of treated organic fiber cords, where the side reinforcement layer is asymmetrically positioned on the outer side of the tire when mounted, reducing the number of carcass plies and maintaining pinch cut resistance while optimizing conicity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the number of carcass plies is increased to improve pinch cut resistance, then durability is improved, but tire weight increases

Engineering Contradiction:
Improvepinch cut resistanceVSAvoidtire weight
Core Design Contradiction:
ReliabilityVSWeight of moving object

Solution Approach 1:

The patent applies different reinforcement strategies to different regions of the tire. Specifically, it uses a side reinforcement layer with organic fiber cords in the sidewall region to improve pinch cut resistance, while maintaining a lighter carcass structure in other areas. This localized reinforcement approach ensures durability where needed without unnecessarily increasing overall tire weight.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent employs composite material structures by combining organic fiber cords with rubber to create the side reinforcement layer. This composite construction provides enhanced mechanical properties for resisting pinch cuts while maintaining weight efficiency compared to using additional full carcass plies.

Inventive Principle:
Principle #40Composite materials

2Reliability

If the number of carcass plies is increased to improve pinch cut resistance, then durability is improved, but device complexity increases

Engineering Contradiction:
Improvepinch cut resistanceVSAvoidcarcass structure complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

Instead of uniformly increasing carcass plies throughout the tire, the invention applies reinforcement locally to the sidewall region where pinch cut resistance is most needed. This selective approach simplifies the overall carcass structure while still achieving the desired durability improvement in critical areas.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent segments the reinforcement function by separating the side reinforcement layer from the main carcass plies. The side reinforcement layer with organic fiber cords is positioned specifically in the sidewall region, allowing independent optimization of pinch cut resistance without complicating the overall carcass construction.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP3176009B1Pneumatic tyre
Publication Date: 2018.11.21 BRIDGESTONE CORP
  • EP3176009B1 patent drawingFigure 1
  • EP3176009B1 patent drawingFigure 2~3
  • EP3176009B1 patent drawingFigure 4

AI summary

In the pneumatic tire of this disclosure, a side reinforcement layer is arranged inside a carcass main body, the side reinforcement layer formed of a treated member, the treated member formed by coating with rubber organic fiber cords extending parallelly to ply cords of a carcass ply of the carcass main body, only on a sidewall portion of a half portion on one tire widthwise side partitioned by a tire equatorial plain; at an unloaded condition, when the pneumatic tire is mounted to an applicable rim and is applied with a prescribed internal pressure, a tire radial inner end of the side reinforcement layer is located on a side inner in the tire radial direction than a tire radial outermost position of a rim flange, and a tire radial outer end of the side reinforcement layer overlaps the belt by 5 mm or more in a tire widthwise direction; and the tread portion has one or more circumferential main grooves extending in a tire circumferential direction, and at an unloaded condition, when the pneumatic tire is mounted to an applicable rim and is applied with a prescribed internal pressure, a contact width of a tire widthwise outermost land portion partitioned by the one or more circumferential main grooves and a tread edge on one tire widthwise side is larger than a contact width of a tire widthwise outermost land portion partitioned by the one or more circumferential main grooves and a tread edge on the other tire widthwise side.