Biopsy Forceps Cam Trigger for Rotation Without Blocking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing surgical devices for biopsy face issues such as undesirable blocking of the actuation mechanism and difficulty in adjusting the orientation of forceps, particularly when used with instruments like anoscopes and rectoscopes.
Innovation Solution
A surgical device with a rotatable external element and biopsy forceps that can be adjusted via a cam-actuated mechanism, preventing unwanted misalignments and blocking by maintaining the actuation mechanism on a parallel axis, allowing easy orientation and reliable operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a trigger mechanism is used for actuation, then the forceps can be controlled to remove tissue, but the mechanism may be blocked by forces applied in unwanted directions
Solution Approach 1:
A cam mechanism is introduced as an intermediary between the trigger and the forceps actuation. The cam converts the trigger's linear motion into rotational motion, which then drives the forceps closure through a separate linkage. This intermediary mechanism isolates the forceps actuation from direct trigger forces, preventing blocking while maintaining control.
Solution Approach 2:
The direct linear actuation mechanism is replaced with a cam-based rotational mechanism. The cam profile is designed to convert the trigger's linear displacement into controlled rotational movement of the forceps closure, eliminating the direct transmission of unwanted forces that cause blocking.
2Device complexity
If the forceps are fixed in orientation, then the structure is simple, but it is difficult to adjust the orientation to better remove tissue fragments
Solution Approach 1:
The forceps assembly is made dynamically adjustable by incorporating a rotation mechanism that allows the forceps to be rotated to different orientations. This dynamic capability enables the forceps to be adapted to different tissue locations and fragment orientations without increasing overall structural complexity.
Solution Approach 2:
The forceps assembly is segmented into a rotatable external element and the forceps themselves. This segmentation allows the forceps to be independently rotated relative to the main device body, providing orientation adjustment while keeping the overall structure relatively simple.
3Productivity
If the actuation mechanism is directly connected to the forceps, then the transmission is direct, but misalignment causes blocking
Solution Approach 1:
The cam mechanism serves as an intermediary that decouples the direct linear transmission from the forceps closure. By converting linear motion to rotational motion through the cam profile, the system maintains efficient actuation transmission while preventing misalignment-induced blocking.
Solution Approach 2:
The actuation transmission is moved from a one-dimensional linear path to a two-dimensional rotational path through the cam mechanism. This dimensional change allows the forceps to close smoothly while the cam absorbs misalignment forces that would otherwise cause blocking.
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
Prevents actuation mechanism blocking and facilitates easy adjustment of forceps orientation, ensuring smooth and effective tissue sampling without mechanical interference.
Implementation Method 1
an actuation mechanism for the forceps, disposed inside the external structure... the actuation mechanism comprises a main structure movable inside the external structure between a rest position in which the main structure is proximal to the external element and a distanced position in which the main structure is distal relative to the external element
Implementation Method 2
The external element is rotatable about its main axis of extension... during use the biopsy forceps are rotatable together with the external element about the main axis of extension of the external element
Implementation Method 3
the actuation mechanism comprises a return spring connected to a proximal end of the main structure and configured to bring the main structure back from the distanced position to the rest position
Data Source
AI summary
A surgical device for biopsy includes an external structure having a handle, which is disposed in a proximal portion of the external structure for being gripped by a user, an external element insertable, during use, into a cavity, biopsy forceps retained by the external element, an actuation mechanism for the forceps, disposed inside the external structure, and a trigger pivoted and solidly joined to the external structure and engaged with the actuation mechanism. A main structure of the actuation mechanism includes a pin and the trigger has a through hole shaped like a cam and pivoted on the pin of the main structure of the actuation mechanism.