Surgical Tool Force Limiter Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Minimally invasive surgical instruments often have limited control and range of motion, making it difficult to maneuver through tight spaces and increasing the risk of trauma to surrounding tissues, particularly in procedures like laparoscopy and endoscopy, due to their rigid design and limited articulation.
Innovation Solution
The implementation of a force limiter mechanism in surgical tools that limits the actuation force delivered to the end effector, using a superelastic shape memory material spring or tension bearing member to prevent excessive force transmission, allowing for controlled movement and reduced tissue trauma.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If conventional rigid surgical instruments are used, then structural strength is maintained, but control precision and range of motion are limited
Solution Approach 1:
The patent applies dynamics by making the instrument shaft flexible rather than rigid, allowing it to bend and articulate to follow the natural curvature of the gastrointestinal tract. The flexible shaft with articulation joints enables dynamic adaptation to anatomical structures while maintaining control precision through the force limiter mechanism that prevents excessive bending forces.
2Force
If more force is applied to advance the instrument, then penetration capability is improved, but tissue trauma increases
Solution Approach 1:
The force limiter mechanism serves as a beforehand cushioning element by being pre-configured with a maximum force threshold. When the actuation force reaches this predetermined limit, the force limiter engages to absorb or block additional force, preventing excessive force transmission to the tissue and thereby cushioning against potential trauma before it occurs.
3Adaptability or versatility
If the instrument shaft is made more flexible to improve maneuverability, then range of motion is improved, but structural strength is reduced
Solution Approach 1:
The patent employs flexible shells by constructing the shaft from multiple articulated segments or flexible materials that can bend while maintaining structural integrity. The flexible shaft design allows significant range of motion to navigate complex anatomical pathways while the segmented construction and force limiter prevent excessive bending that would compromise structural 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
Enhances the control and range of motion of surgical instruments by limiting the force applied to tissues, reducing the risk of trauma and improving precision during minimally invasive procedures, thereby reducing operative time and improving surgical outcomes.
Implementation Method 1
using a superelastic shape memory material spring or tension bearing member to prevent excessive force transmission
Data Source
AI summary
The invention provides surgical or diagnostic tools and associated methods that offer improved user control for operating remotely within regions of the body. In some embodiments these tools include a proximally-located actuator for the operation of a distal end effector, as well as proximally-located actuators for articulational and rotational movements of the end effector. Control mechanisms and methods refine operator control of end effector actuation and of these articulational and rotational movements. A force limiter mechanism protects the end effector and manipulated objects from the harm of potentially excessive force applied by the operator. The tool may also include other features. A multi-state ratchet for end effector actuation provides enablement-disablement options with tactile feedback. An articulation lock allows the fixing and releasing of both neutral and articulated configurations of the tool and of consequent placement of the end effector. A rotation lock provides for enablement and disablement of rotatability of the end effector.