Flexible Retro-Reflective Outsole for Footwear Visibility
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Solution Overview
Problem
Existing footwear designs with reflective materials fail to effectively cover the entire outsole surface without reducing the flexibility of the outsole, and existing solutions either provide a slow response or require bulky designs that are cumbersome and difficult to manufacture.
Innovation Solution
A reflective outsole design featuring a flexible retro-reflective device that covers the majority of the outsole's lower surface, excluding areas around tread elements, allowing for enhanced visibility without compromising the outsole's flexibility, achieved by using a thin, flexible material with retro-reflective properties and a base layer attached during the molding process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If reflective materials are embedded into the outsole using existing methods (strips or pieces), then visibility is improved, but the outsole flexibility is reduced and the design becomes bulky
Solution Approach 1:
The patent applies a thin, flexible reflective film to the outsole surface instead of embedding bulky strips or pieces. This film can be molded directly onto the outsole during the manufacturing process, providing comprehensive coverage while maintaining the flexibility and simplicity of the original outsole design. The thin film approach eliminates the need for holes, recesses, or complex embedding structures.
2Illumination intensity
If reflective strips are embedded into the outsole, then visibility is improved, but manufacturing complexity increases due to requiring holes and recesses
Solution Approach 1:
The reflective film is applied to the outsole during the molding process itself, before the outsole is fully cured. This preliminary application allows the reflective pattern to be integrated into the outsole structure in a single manufacturing step, eliminating the need for subsequent operations to create holes, recesses, or to embed separate reflective components.
3Illumination intensity
If phosphorescent materials are used to illuminate the footwear, then visibility in the dark is improved, but the response time to incoming light is slow and the glow is dim
Solution Approach 1:
Instead of using phosphorescent materials that absorb and slowly re-emit light, the patent uses retro-reflective materials that immediately reflect incoming light back toward its source. This creates an instantaneous response to headlights or other light sources, providing a bright, immediate signal to drivers without the delayed, dim glow characteristic of phosphorescent materials.
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 solution provides instantaneous and bright reflection, improving visibility in low light conditions without reducing the outsole's flexibility or requiring cumbersome designs, effectively alerting others to the wearer's presence while maintaining the outsole's performance and aesthetic appeal.
Implementation Method 1
Retro-reflective materials reflect incoming light regardless of the angle of incidence. Unlike phosphorescent materials, which emit light slowly, retro-reflective materials emit light almost instantaneously, allowing for a very bright response to incident light.
Data Source
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AI summary
An article of footwear including a reflective outsole is disclosed. The article of footwear has an outsole including a reflective device that covers one or several portions of the outsole. The reflective device is composed of a thin and flexible material that does interfere with the natural flexibility of the outsole. The reflective device may extend over a substantial majority of a lower surface of the outsole, including a portion of the outer periphery of the outsole.