Retrieval Device End Effector Loop Capture Mechanism

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current retrieval devices face challenges in effectively capturing and removing objects from within a patient's body, particularly those not positioned on the side of the end effector, due to their open-end or closed-end designs.

Innovation Solution

A retrieval device with a sheath and end effector featuring expandable and contractible arms that form a loop, allowing for improved object capture and release, with a handle assembly to control the end effector's movement between expanded and contracted states.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If an open-end design end effector is used, then objects can enter through the front loop, but objects may escape under certain conditions

Engineering Contradiction:

Improveobject capture capabilityVSAvoidobject retention reliability

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

The end effector is divided into multiple arms (first arm, second arm, third arm, and optionally fourth arm) that can independently articulate and position themselves around the object. Each arm can be controlled separately to achieve precise encirclement and secure capture, preventing object escape while maintaining ease of insertion.

Inventive Principle:

Principle #1Segmentation

2Reliability

If a closed-end design end effector is used, then object capture may be more secure, but objects not positioned on the side of the end effector are difficult to capture

Engineering Contradiction:

Improveobject retention reliabilityVSAvoidobject capture versatility

Core Design Contradiction:

ReliabilityVSAdaptability or versatility

Solution Approach 1:

The end effector employs dynamic articulation mechanisms allowing arms to move relative to each other, transitioning between open and closed configurations. This enables the end effector to adapt to objects positioned at various locations, capturing objects from the side while maintaining secure retention when closed.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The end effector adds a dimensional aspect by allowing arms to articulate in multiple directions and planes, not just linear opening/closing. This multi-planar movement capability enables capture of objects positioned laterally or at angles, significantly improving versatility while maintaining reliable closure.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

3Ease of operation

If the end effector is expanded for object entry, then capture capability is improved, but device complexity increases

Engineering Contradiction:

Improveobject capture capabilityVSAvoidend effector structure complexity

Core Design Contradiction:

Ease of operationVSDevice complexity

Solution Approach 1:

The end effector arms are nested within each other or within the sheath when in a contracted state, minimizing profile during insertion. Upon deployment, the arms expand outward in a controlled sequence to form the capture loop, achieving complex capture capability without proportionally increasing overall device complexity.

Inventive Principle:

Principle #7Nested doll (Nesting)

Data Source

PatentUS20250090186A1Retrieval devices and related methods of use

Publication Date: 2025.03.20 BOSTON SCIENTIFIC SCIMED INC

AI summary

According to one aspect, a retrieval device may include a sheath having a distal end. The retrieval device may also include an end effector movable relative to the distal end of the sheath. The end effector may include first and second arms. The first arm may include a first opening at a distal portion of the first arm. The second arm may include a second opening at a distal portion of the second arm. The end effector may also include a third arm. The third arm may be slidably received in the first and second openings. A distal portion of the third arm may form at least part of a loop. The loop may extend through the first and second openings.