Double-Curved Elastomer Tread Molding for Precise Tire Fit
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for molding elastomeric tire treads, especially for bicycles and motorbikes, face challenges in achieving precise double curvature, leading to poor fit, increased defects, and reduced grip due to deformation when attached to curved tires, and require complex and time-consuming processes.
Innovation Solution
A mold with inner longitudinal cavities featuring elevations and depressions that slope both laterally and longitudinally, allowing for the precise molding of double curved elements, which are then inverted to achieve the desired curvature, reducing internal tensions and improving fit on curved tires.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a flat mold is used to mold tire treads, then the manufacturing process is simpler, but the tread pattern deforms and grooves open or expand when attached to a round tire, affecting road grip
Solution Approach 1:
The patent applies curvature to the mold surface by providing elevations and depressions that slope laterally and longitudinally, creating a double-curved mold geometry that matches the curvature of the tire. This allows the tread to be molded in its final curved shape, eliminating deformation when attached to the tire while maintaining manufacturing simplicity through a single-mold process
2Shape
If traditional round molds with expandable airbags are used, then the mold can accommodate tire curvature, but the casting precision is reduced and defect rate increases
Solution Approach 1:
The patent incorporates the curvature directly into the mold structure through elevations and depressions, so the tread is pre-formed in its final curved shape during molding. This eliminates the need for subsequent expansion or deformation steps, achieving both curvature accommodation and high casting precision in a single operation
Solution Approach 2:
The double-curved mold geometry with lateral and longitudinal slopes creates a precise form that matches the target tire curvature, allowing the elastomeric material to be molded directly into the correct shape without requiring expandable airbags or post-molding deformation
3Ease of operation
If elastomeric material is stretched to fit onto the tire, then the fit may be acceptable, but the sipes and grooves are disturbed and grip is changed
Solution Approach 1:
The tread is pre-formed in its final curved shape during molding, so no stretching or deformation is required during mounting. The sipes and grooves are already in their correct positions and orientations, preserving their integrity and intended grip characteristics while maintaining ease of installation
4Productivity
If a flat mold is used, then the manufacturing process is faster, but the tread will not fit close onto a tire with laterally curved tread
Solution Approach 1:
The mold incorporates double curvature through elevations and depressions that slope both laterally and longitudinally, allowing the tread to be molded directly in its final curved shape. This eliminates the need for complex multi-step processes while achieving precise fit on tires with laterally curved treads
Solution Approach 2:
The curved shape is created during the initial molding process rather than requiring subsequent forming or stretching operations, maintaining high manufacturing speed while achieving the required tread curvature for proper tire fit
Data Source
AI summary
A mold for a longitudinal element of elastomeric material has a housing including at least one longitudinal inner cavity extending between at least two opposing main walls and two opposing edge walls. The main walls of the cavity have elevations extending and sloping both laterally and longitudinally of the cavity, and depressions extending and sloping both laterally and longitudinally of the cavity. Further, an elevation of one wall is opposite to a depression of the other wall.