Conductive Tire Sidewall Passages via Solvent Evaporation
Solution Overview
Problem
Pneumatic vehicle tires with electrically non-conductive sidewalls require effective methods to dissipate electrostatic charges generated during driving, as tires filled with silica have lower electrical conductivity compared to those filled with soot, necessitating the creation of electrically conductive passages for charge dissipation.
Innovation Solution
A method involving the application of an electrically conductive suspension, comprising a conductive rubber mixture and a volatile organic solvent with a boiling point less than 100 °C, is applied using printing processes to form conductive passages within the tire, particularly on the sidewall and horn profile areas, ensuring co-vulcanization and efficient integration into the tire manufacturing process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If silica-filled rubber compounds are used in tire components, then rolling resistance is reduced and wet grip is improved, but electrical conductivity deteriorates
Solution Approach 1:
The patent applies local quality by creating electrically conductive passages in specific locations (sidewall, belt rubber coating, or inner layer) while maintaining silica-filled rubber compounds in other areas. This allows different regions of the tire to have different electrical conductivity properties, enabling charge dissipation pathways without compromising the low rolling resistance and wet grip provided by silica-filled compounds in the tread and other components.
Solution Approach 2:
The patent employs composite materials by combining silica-filled rubber compounds with conductive fillers (such as carbon black or metal particles) in specific tire components. This creates a composite structure where the silica provides low rolling resistance and wet grip, while the conductive filler provides the necessary electrical conductivity for charge dissipation, resolving the contradiction between these two properties.
2Reliability
If electrically conductive passages are created in silica-filled tires, then electrostatic charge dissipation is enabled, but manufacturing complexity increases
Solution Approach 1:
The patent applies preliminary action by incorporating conductive fillers into the rubber compound mixture before the tire manufacturing process. The conductive material is mixed with the silica-filled rubber compound in advance, and the passages are formed as integral parts of the tire structure during vulcanization, rather than adding complex post-processing steps to create conductive pathways.
Solution Approach 2:
The patent uses the rubber compound itself as an intermediary medium that combines both silica filler and conductive filler particles. This intermediary material serves dual functions: maintaining the low rolling resistance and wet grip properties of silica-filled rubber while providing continuous conductive pathways for charge dissipation, thereby simplifying the overall manufacturing process.
3Reliability
If conductive material is added to tire components, then electrical conductivity is improved, but material composition complexity increases
Solution Approach 1:
The patent applies parameter changes by carefully controlling the concentration and distribution of conductive fillers in the rubber compound. By optimizing the amount of conductive filler (such as carbon black or metal particles) and its particle size distribution, the patent achieves sufficient electrical conductivity while maintaining the stability and performance characteristics of the silica-filled rubber compound.
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
This method reliably creates electrically conductive passages in tires, effectively dissipating electrostatic charges by ensuring good contact and co-vulcanization with adjacent tire components, enhancing the tire's electrical conductivity without compromising existing properties.
Implementation Method 1
Due to its volatility, the organic solvent of the conductive suspension evaporates within a short time after application, so that the conductive rubber mixture remains in the form of a thin layer on the respective electrically non-conductive tire component.
Data Source
Figure 1
AI summary
A method for producing an electrically conductive passage in a vehicle tire, which runs in the sidewall area between an electrically conductive tread section and an electrically conductive bead component that, when the tire is mounted on a rim, is in electrically conductive contact with the rim. On one side of at least one raw tire component, which extends across the sidewall area in the finished tire, an electrically conductive suspension (3) consisting of at least one electrically conductive rubber compound and an organic solvent with a boiling point below 100°C is applied as an electrically conductive passage(s) in line or strip form or over a surface, in particular over the entire surface.