Vertically Movable Knife in Surgical Stapling Device
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing surgical stapling devices face issues with tissue accumulation and slippage due to horizontal force applied by the knife blade during staple formation, which can negatively impact staple formation efficiency.
Innovation Solution
The surgical stapling device incorporates an actuation sled assembly with a knife that moves vertically within the tissue gap, leveraging micro-serrations on the cutting edge to enhance cutting efficiency, and includes a guide member and biasing mechanism to facilitate linear and reciprocating movement of the knife between extended and retracted positions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the knife blade moves horizontally through the tool assembly to cut tissue, then the cutting action is simple and direct, but tissue accumulation and slippage occur during staple formation which negatively impacts staple formation quality
Solution Approach 1:
The knife blade is modified to move not only horizontally but also vertically within the tissue gap. The vertical movement component is achieved through a cam mechanism that converts horizontal actuation sled movement into vertical knife blade motion. This dimensional change allows the knife to engage tissue more effectively and prevents tissue slippage during cutting and staple formation, thereby improving staple formation quality while maintaining cutting efficiency.
Solution Approach 2:
The knife blade system transitions from a static horizontal cutting path to a dynamic reciprocating motion with both horizontal and vertical components. The cam mechanism enables the knife to reciprocate vertically during its horizontal traversal, creating a more dynamic cutting action that maintains better contact with tissue throughout the cutting process, preventing slippage and improving staple formation reliability.
2Productivity
If micro-serrations are added to the cutting edge to enhance cutting efficiency, then cutting performance improves, but the knife structure becomes more complex
Solution Approach 1:
Micro-serrations are applied only to the cutting edge portion of the knife blade where they are most needed for enhanced cutting efficiency. This localized application of a complex feature minimizes the overall increase in structural complexity while maximizing the benefit at the critical cutting interface. The rest of the knife blade maintains a simpler structure.
Data Source
AI summary
A surgical stapling device includes a tool assembly having an actuation sled assembly that includes an actuation sled and a knife movably supported on the actuation sled. The tool assembly includes structure for moving the knife in relation to the actuation sled between extended and retracted positions in response to movement of the actuation sled through a staple cartridge of the tool assembly. Movement of the knife moves a cutting edge of the knife in relation to the actuation sled within a tissue gap defined by the tool assembly to impart a degree of vertical motion to the cutting edge of the knife. This enables the tool assembly to leverage micro-serrations on the cutting edge of the knife to enhance cutting efficiency of the knife.