Heel Spring Structure for Hands-Free Footwear Entry
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional footwear requires the use of one or both hands to stretch the ankle opening and hold the rear portion during foot insertion, especially in soft uppers without a heel counter.
Innovation Solution
A heel spring device that surrounds the foot-receiving cavity at the heel region, comprising a control bar with side arms and a base, biased to an unloaded position that elastically deforms under force to a loaded position, allowing hands-free foot entry by storing potential energy for return to the unstressed position.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a soft upper without heel counter is used, then comfort and flexibility are improved, but ease of foot insertion deteriorates requiring manual stretching
Solution Approach 1:
The heel spring device is pre-loaded in the factory to a specific force level that automatically stretches the ankle opening when the foot is inserted. This preliminary action eliminates the need for manual stretching by the consumer while maintaining the soft, comfortable upper construction.
Solution Approach 2:
The heel spring device serves itself by using the insertion force to automatically stretch and position the ankle opening. The device self-regulates the stretching action through its spring mechanism, eliminating the need for external manual intervention while maintaining comfort.
2Ease of operation
If hands-free foot entry is enabled, then ease of operation is improved, but device complexity increases due to additional components
Solution Approach 1:
The heel spring device merges the functions of a spring mechanism, a positioning structure, and a stretching aid into a single integrated component. This combination achieves hands-free foot entry while minimizing the number of separate parts and assembly steps.
Solution Approach 2:
The heel spring device uses parameter changes in the spring force and geometry to achieve hands-free operation. By carefully selecting the spring constant, pre-load force, and geometric dimensions, the device provides automatic stretching without requiring complex control mechanisms or multiple components.
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
Enables easy and hands-free foot entry into footwear by using the heel spring device to widen the ankle opening, reducing the need for manual adjustment during insertion.
Implementation Method 1
The control bar is biased to an unloaded position with the center segment a first distance from the base, and elastically deforms under an applied force to a loaded position with the center segment a second distance from the base less than the first distance
Data Source
AI summary
A device configured to surround a portion of a foot-receiving cavity at a heel region of an article of footwear comprises a control bar having a center segment, a first side arm extending from the center segment, and a second side arm spaced from the first side arm and extending from the center segment. The control bar may include a series of slats. A base supports the control bar and is connected to the first side arm and the second side arm. The control bar is biased to an unstressed position with the center segment a first distance from the base, and elastically bends under an applied force to a loaded position with the center segment a second distance from the base less than the first distance. The device stores potential energy that returns the control bar to the unloaded position upon removal of the applied load.