Fluid-Filled Sole Chambers with Stitched Tensile Members for Flex Grooves
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional fluid-filled chambers in footwear sole structures experience increased stiffness due to tensile members that limit their flexibility when inflated, necessitating a need for chamber configurations that provide increased flexibility while maintaining a planar shape.
Innovation Solution
The introduction of a tensile member configuration with bonded barrier layers and stitching through select portions, allowing the chamber to maintain a reduced thickness and flexibility by restricting expansion, particularly in areas requiring greater flexibility, such as the ball of the foot.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Shape
If tensile members are added to the chamber to maintain planar shape, then the chamber maintains a substantially planar configuration, but the chamber stiffness increases and flexibility decreases
Solution Approach 1:
The tensile member is divided into multiple discrete stitching segments distributed across the chamber surface. Instead of a continuous rigid structure, the stitching creates localized reinforcement points that maintain planar shape without forming a stiff continuous framework, allowing flexibility between stitch locations.
Solution Approach 2:
The tensile member provides localized reinforcement at specific stitching points rather than uniform reinforcement across the entire chamber. This allows the chamber to maintain planar shape where needed while preserving flexibility in non-stitched areas, creating different mechanical properties in different locations.
2Shape
If tensile members are added to the chamber to maintain planar shape, then the chamber maintains a substantially planar configuration, but the chamber becomes stiffer
Solution Approach 1:
The tensile member is segmented into discrete stitching points rather than continuous structure. This segmentation prevents the formation of a stiff continuous framework while still providing localized shape control at each stitch location, reducing overall chamber stiffness.
Solution Approach 2:
The chamber utilizes the flexible bladder material in conjunction with discrete stitching points. The flexible film maintains planar shape through localized reinforcement rather than rigid structures, preserving the inherent flexibility of the thin film while preventing excessive deformation.
3Ease of operation
If the chamber thickness is reduced to increase flexibility, then the chamber flexibility increases, but the chamber may lose structural integrity
Solution Approach 1:
The tensile member stitching provides localized reinforcement at specific points in the chamber. This allows the chamber to have reduced overall thickness for flexibility while maintaining structural integrity at critical locations where stitching provides concentrated strength.
Solution Approach 2:
The chamber combines the flexible bladder material with the tensile member stitching to create a composite structure. The stitching acts as a reinforcement layer that provides structural integrity to the reduced-thickness chamber, creating a composite system with both flexibility and strength.
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 configuration enhances the flexibility of the chamber by creating flex grooves in desired areas, providing a more natural foot motion and improved cushioning without compromising the chamber's ability to maintain a substantially planar shape.
Implementation Method 1
Upon inflation, such chambers experience pressure that is evenly distributed to all portions of the inner surface of the bladder material from which the chamber is formed
Implementation Method 2
the first tensile member layer is held in contact with the second tensile member layer by the stitching in the stitched region
Data Source
AI summary
A chamber for receiving a pressurized fluid may include a tensile member extending between a first chamber barrier layer and a second chamber barrier layer and including a plurality of tethers extending between the first tensile member layer and the second tensile member layer. The chamber may include stitching through the tensile member in a stitched region. When the chamber is pressurized with the pressurized fluid, a substantial majority of the first tensile member layer is separated from the second tensile member layer by a distance that corresponds to a length of the plurality of tethers. In addition, the first tensile member layer is held in contact with the second tensile member layer by the stitching in the stitched region, thereby forming an area of the chamber having a reduced thickness relative to adjacent portions of the chamber.