Segmented Overlay Layer Reduces Tire Rolling Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Pneumatic tires face issues with high rolling resistance due to bead flexure and heat buildup, particularly in severe operating conditions, leading to separation of components with disparate properties, and tread groove deformation contributing to increased rolling resistance.
Innovation Solution
Incorporating a belt structure with an overlay layer between the carcass ply and tread, featuring a reinforced ply or fabric with axial widths between 70% and 200% of the circumferential groove width, oriented between -5 degrees to +5 degrees relative to the equatorial plane, and composed of materials like polyester, polybenzobisoxazole, nylon, aramid, and high tensile steel, to reduce distortion and rolling resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the tire operates under severe conditions with high flexure, then the tire maintains structural integrity, but heat buildup increases and causes separation of components with disparate properties
Solution Approach 1:
The patent employs a composite belt structure combining steel belt layers with thermoplastic polymer overlay strips. This composite construction allows the steel layers to provide structural strength while the thermoplastic overlay reduces heat buildup and flexure, directly addressing the contradiction between maintaining structural integrity and reducing heat generation under severe operating conditions
Solution Approach 2:
The patent changes the physical parameters of the belt structure by introducing thermoplastic polymer layers with specific mechanical and thermal properties. The overlay strips have controlled thickness (0.5-5mm) and material composition that alters the heat generation and flexure characteristics of the belt, enabling the tire to withstand severe conditions with reduced heat buildup
2Stability of the object's composition
If the overlay strips are made wider than the circumferential grooves, then tread groove deformation is reduced, but the complexity of the belt structure increases
Solution Approach 1:
The patent applies local quality by positioning overlay strips specifically underneath circumferential grooves with widths exceeding the groove width. This localized placement provides targeted support exactly where tread groove deformation occurs, rather than uniformly reinforcing the entire belt structure, thus reducing deformation while minimizing added complexity
3Loss of energy
If the overlay layer axial width is between 70% and 200% of the circumferential groove width, then rolling resistance is reduced, but the manufacturing precision requirements increase
Solution Approach 1:
The patent specifies a parameter range (70%-200% of groove width) for the overlay layer axial width rather than a single fixed value. This parameter range provides manufacturing flexibility while still achieving the goal of reduced rolling resistance, as the extended width ensures adequate support without requiring ultra-precise manufacturing control
Data Source
Figure 1
AI summary
A pneumatic tire comprising a pair of axially spaced apart annular bead cores (28a, 28b), a carcass ply (14), a tread (12) comprising at least one circumferential groove (41) and a belt structure disposed radially between the carcass ply (14) and the tread (12); the belt structure comprising at least one belt layer (16, 18, 20) and an overlay comprising at least one overlay layer (51); the overlay layer is disposed radially between the at least one belt layer (16, 18, 20) and the radially innermost surface of the circumferential groove (41); the overlay layer (51) is disposed under the circumferential groove (41) and has an axial width between 70% and 200% of an axial width of the circumferential groove (41) and is a reinforced ply layer or a layer comprising a fabric.