Linear Stapler End Effector With Asymmetric Anvil Pockets
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing open linear staplers experience issues with torque generation during staple firing, leading to misalignment of the staple cartridge with the anvil, resulting in poor sealing and leakage risks due to uneven staple clearances.
Innovation Solution
The end effector design includes a welded anvil connection to outer clamping plates, off-center tissue retaining pin hole, and asymmetric staple forming pockets to ensure precise alignment and balanced force distribution, minimizing clearance and leakage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a conventional stapler design with symmetric staple forming pockets is used, then the structure is simple and easy to manufacture, but lateral force generates torque against the anvil during firing, leading to misalignment of the staple cartridge with the anvil
Solution Approach 1:
The anvil employs asymmetric staple forming pockets where the first staple forming pocket has a different shape from the second staple forming pocket. This asymmetry is designed to balance the lateral forces generated during staple firing, preventing torque against the anvil and ensuring transverse alignment between the staple cartridge and anvil without requiring complex alignment mechanisms
2Reliability
If the anvil is designed with asymmetric staple forming pockets to balance lateral forces, then transverse alignment is improved, but the manufacturing process becomes more complex
Solution Approach 1:
The asymmetric staple forming pockets are designed with specific geometric variations that balance lateral forces during firing. While the pockets are asymmetric, the overall anvil structure remains relatively simple, and the asymmetry can be incorporated into standard manufacturing processes such as molding or machining, avoiding excessive complexity in production
3Manufacturing precision
If symmetric staple forming pockets are used, then the anvil structure is simple, but uneven clearance between adjacent stitches causes poor sealing performance and leakage
Solution Approach 1:
The asymmetric configuration of the staple forming pockets ensures uniform clearance between adjacent stitches by balancing the lateral forces during staple deformation. This prevents the staggered alignment that occurs with symmetric pockets, ensuring consistent sealing performance without requiring additional alignment mechanisms or increasing overall device complexity
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An end effector includes a substantially U-shaped stationary jaw located distally and a movable jaw movable relative to the stationary jaw to clamp tissue therebetween. The stationary jaw includes an anvil at a surface opposite to the movable jaw. The movable jaw is configured to receive a staple cartridge. A surface of the anvil opposite to the movable jaw defines a tissue engagement surface that defines a longitudinal axis and is provided with a first staple forming pocket pair and a second staple forming pocket pair located at two sides of the longitudinal axis. The first staple forming pocket pair and the second staple forming pocket pair each are configured as a centrosymmetric structure formed by two staple forming pockets arranged along the longitudinal axis, and the staple forming pocket has an asymmetric shape. Corresponding staple forming pockets in the first staple forming pocket pair and the second staple forming pocket pair are opposite to each other in shape orientation along a transverse direction perpendicular to the longitudinal axis. The end effector can achieve better transverse alignment of the staple cartridge with the anvil during staple firing and provide a better sealing effect.