Rotational Stent Graft Deployment Device with Sequential Screw Threads
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing stent graft deployment devices lack a mechanism to ensure sequential and error-reduced actions for releasing stent grafts in the vasculature, leading to potential operator errors during deployment.
Innovation Solution
A deployment device with a rotating handle that includes concentric screw threads and a release clamp mechanism, allowing for controlled longitudinal movement of the release handle to sequentially release the stent graft by rotating and retracting the sheath, ensuring precise and ordered deployment actions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a simple deployment mechanism is used, then device complexity is reduced, but operator error risk increases due to lack of sequential control
Solution Approach 1:
The deployment mechanism is segmented into distinct functional components: a rotator component with first and second screw threads, a release clamp with engagement features, and a sheath retraction system. Each segment performs a specific sequential action (rotating the handle, engaging the clamp, retracting the sheath) to ensure controlled deployment while maintaining overall system reliability.
Solution Approach 2:
The release clamp is pre-configured with engagement features that interact with the screw threads before deployment begins. The first screw thread is designed to engage the release clamp initially, and the second screw thread engages afterward, creating a predetermined sequence of actions that guides the operator through proper deployment steps and prevents errors.
2Ease of operation
If a rotational control mechanism with multiple screw threads is used, then sequential deployment control is improved, but device complexity increases
Solution Approach 1:
Multiple screw threads (first and second) are integrated into a single rotator component, allowing sequential engagement of the release clamp through continuous rotational motion. This merging of functions into one component achieves precise sequential control without requiring separate mechanisms for each deployment step, thereby limiting the increase in overall device complexity.
Solution Approach 2:
The rotator component serves multiple functions: it provides the primary rotational input, engages the release clamp through the first screw thread, and subsequently engages the second screw thread for continued control. This multi-functionality allows a single component to manage the entire sequential deployment process, improving ease of operation while avoiding the need for additional specialized components.
3Manufacturing precision
If the release clamp is engaged into concentric screw threads, then longitudinal movement precision is improved, but manufacturing complexity increases
Solution Approach 1:
The screw threads are formed as concentric helical structures on the rotator component, creating a curved three-dimensional engagement path for the release clamp. This helical geometry converts simple rotational motion into precise longitudinal movement, achieving high manufacturing precision through a standardized curved form that can be manufactured using conventional CNC machining or threading processes.
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 device enables precise and sequential release of the stent graft, reducing operator error and ensuring proper deployment by using a combination of rotational and longitudinal movements to engage and disengage the release clamp, thereby minimizing the chances of incorrect deployment.
Implementation Method 1
The rotator component has a first screw thread with a portion of the release handle engaged into the first screw thread so that rotation of the rotator component causes longitudinal movement of the release handle through the fixed handle
Implementation Method 2
The rotator component has a second screw thread with a portion of the release clamp engaged into the second screw thread whereby rotational movement of the rotator component causes longitudinal movement of the release clamp with respect to the pusher assembly
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A stent graft deployment device assembly (10) has a cylindrical fixed handle (6) to be gripped and held by a user and an tubular release handle (30) extending through the fixed handle. The release handle can be moved through the fixed handle. The deployment device assembly has a pusher assembly and a sheath (18) to cover a stent graft on the pusher assembly. The pusher assembly is connected to the fixed handle and the sheath is connected to the release handle so that retraction of the release handle through the fixed handle causes the sheath to be retracted from the stent graft on the pusher assembly. The fixed handle has a rotator component (36) with internal first and second screw threads. The tubular release handle has an external screw thread (31) which engages with the first screw thread. The external screw thread (31) can extend along part, all or in segments along the release handle. A release clamp (48) on the pusher has pins which engage with the second screw thread. Movement of the rotator component with respect to the fixed handle first moves the tubular release handle with respect to the fixed handle and subsequently moves the release clamp on the pusher and thereby pulls the trigger wires.