Balloon Expandable Stent With Interlocking Wavy Annular Members
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Balloon expandable stents used in blood vessels face challenges in achieving a balance between flexibility to follow vessel configurations and maintaining an expanded state retention force, with existing designs either flaring outward or being inflexible.
Innovation Solution
A stent design featuring wavy annular members with apexes that penetrate and engage each other, providing a high expansion retention force while maintaining flexibility by connecting through short connection portions shifted from the apexes, allowing uniform expansion and strength distribution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a balloon expandable stent of the opened cell type is used to achieve flexibility, then the stent can follow the travel direction of blood vessel, but the stratum flares outward
Solution Approach 1:
The stent is divided into multiple unit structures along the axial direction, with each unit containing bent portions that can independently engage with adjacent units. This segmentation allows localized flexibility while maintaining overall shape control through the engagement mechanism between units.
Solution Approach 2:
The apex of bent portions in one wavy annular member penetrates into the space between adjacent bent portions of neighboring members, creating a nested engagement structure. This nesting prevents flare-out by interlocking the units while allowing axial flexibility through the curved approach directions of the apexes.
2Shape
If a balloon expandable stent of the closed cell type is used to prevent flare-out, then the stratum does not flare outward, but the stent is incapable of flexibly following the travel direction of blood vessel
Solution Approach 1:
The stent structure transitions from a static closed-cell design to a dynamic engagement system where the apexes of bent portions can curve in approach directions and penetrate into spaces between adjacent units. This dynamic mechanism provides flexibility while maintaining closed-cell flare-out prevention.
3Strength
If the apexes of bent portions are connected directly to maintain strength, then the stent has high expanded state retention force, but the connection portions become long and reduce flexibility
Solution Approach 1:
Instead of fully connecting apexes with long straight portions, the design uses partial engagement where apexes penetrate into spaces between adjacent bent portions and curve in approach directions. This provides sufficient engagement strength while keeping connection portions short and maintaining flexibility.
Data Source
AI summary
A stent has a plurality of wavy annular members arranged adjacently to each other in an axial direction of the stent with the adjacent wavy annular members connected with each other. Each of the wavy annular members has a plurality of one-end side bent portions each having an apex at one-end side of the stent in an axial direction thereof and a plurality of other-end side bent portions each having an apex at the other-end side of the stent in the axial direction thereof. An apex of each of the one-end side bent portions of each wavy annular member penetrates into a space formed between the adjacent other-end side bent portions of one of the adjacent wavy annular members. An apex of each of the other-end side bent portions of each wavy annular member penetrates into a space formed between the adjacent one-end side bent portions of the other of the adjacent wavy annular members. The apex of the one-end side bent portion of each wavy annular member and the apex of the other-end side bent portion of the adjacent wavy annular member curve in an approach direction, thus engaging each other.