Stent Delivery Actuator Locking Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current stent delivery systems lack effective mechanisms for steering, rotating, pushing, or pulling stents during placement and often fail to prevent premature deployment, which can lead to improper positioning of stents in body lumens.
Innovation Solution
A stent delivery device with a handle assembly, an elongate inner member, and an elongate outer tubular member, featuring an actuator and a locking mechanism that allows for controlled axial movement and deployment of the stent, enabling precise positioning and preventing premature deployment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a stent delivery device is designed with basic advancement capabilities, then the device structure remains simple, but the ability to steer, rotate, push, or pull stents during placement is insufficient
Solution Approach 1:
The handle assembly is designed to perform multiple functions including steering, rotating, pushing, and pulling the stent delivery catheter through a single integrated structure. The actuator mechanism provides both locking and deployment functions, allowing the device to manipulate the stent in various ways without requiring separate specialized tools for each action.
Solution Approach 2:
The actuator serves as an intermediary mechanism between the operator and the stent delivery system. It translates operator input into controlled movements of the inner member relative to the outer member, enabling precise manipulation of the stent during placement while isolating the complexity of the control mechanism from the delivery catheter itself.
2Ease of operation
If a stent delivery device allows free actuator movement for easy deployment, then the deployment process is simple, but premature stent deployment cannot be prevented
Solution Approach 1:
The actuator is designed with dynamic characteristics that change its mobility based on the deployment state. In the locked position, the actuator is constrained and cannot move to prevent premature deployment. When unlocked, the actuator becomes mobile and can be freely actuated to deploy the stent, providing both safety and ease of operation through a single mechanism.
Solution Approach 2:
The locking mechanism uses a simple, reliable mechanical engagement system that can be easily manufactured and integrated into the handle assembly. The locking features are designed as basic mechanical elements rather than complex electronic or chemical systems, ensuring reliability while maintaining ease of manufacture and operation.
3Reliability
If a locking mechanism is added to prevent premature deployment, then deployment control improves, but the actuator movement is restricted
Solution Approach 1:
The locking mechanism dynamically transitions between locked and unlocked states based on operator action. The actuator can be freely moved when unlocked for deployment, and is only constrained when in the locked position to prevent premature deployment. This dynamic behavior resolves the contradiction by providing both unrestricted movement when needed and restriction when safety is required.
Solution Approach 2:
The locking mechanism provides tactile feedback to the operator through its mechanical engagement features. The distinct locked and unlocked positions are physically distinguishable, allowing the operator to understand the current state of the actuator without complex indicators or electronics, thus maintaining ease of operation while ensuring reliable deployment control.
Data Source
Figure 1
Figure 1A
Figure 2
AI summary
A stent delivery device having a locking mechanism. The device includes a handle assembly, an elongate inner member, and an elongate outer tubular member surrounding the elongate inner member. The handle assembly includes a handle attached to one of the inner member and the outer tubular member, and an actuator attached to the other of the inner member and the outer tubular member. Actuation of the actuator relative to the handle between a first position and a second position causes axial movement of the outer tubular member relative to the inner member. The locking mechanism has a locked position in which the actuator is prevented from moving from the first position to the second position and an unlocked position in which the actuator is permitted to move from the first position to the second position.