Arcuate Seal for Minimally Invasive Surgical Access
Solution Overview
Problem
Surgical access assemblies for minimally invasive surgery require robust seals that can adjust to manipulation of surgical instrumentation without compromising seal integrity, but existing seals often suffer from buckling or bending during movement, leading to loss of sealing contact.
Innovation Solution
The surgical access assembly includes an instrument valve housing with a centering mechanism, seal assembly, and guard assembly, featuring a base seal member with an arcuate portion that adjustably engages surfaces of the housing for sealing, and a retainer frame assembly to secure the seal and guard assemblies, ensuring reliable sealing during instrument insertion and manipulation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a seal is made robust to maintain sealing integrity, then sealing reliability is improved, but the seal becomes prone to buckling and bending during movement
Solution Approach 1:
The seal is divided into multiple arcuate seal members (first, second, third, and fourth arcuate seal members) that can independently engage with the housing surfaces. This segmentation allows each segment to maintain its shape and sealing function without buckling, while collectively providing robust sealing integrity across the instrument valve housing.
Solution Approach 2:
The seal members are designed with arcuate (curved) geometries that conform to the cylindrical instrument valve housing. This curvature allows the seals to flex and adapt to radial and off-centered movements while maintaining continuous contact with the housing surfaces, preventing buckling and ensuring sealing reliability during dynamic operation.
2Reliability
If the seal is designed to engage multiple surfaces for robust sealing, then sealing reliability is improved, but the device complexity increases
Solution Approach 1:
Multiple arcuate seal members are combined into a single integrated seal assembly that simultaneously engages with multiple surfaces of the instrument valve housing. This merging approach maintains robust sealing reliability across various movement conditions while reducing the number of separate components and simplifying the overall assembly process.
Solution Approach 2:
The seal assembly is designed to perform multiple sealing functions simultaneously - engaging with the distal surface, lateral surface, and other surfaces of the housing. This multi-functionality allows a single seal assembly to provide comprehensive sealing coverage, reducing the need for multiple separate sealing components and simplifying the device structure.
3Adaptability or versatility
If the seal assembly allows radial movement to accommodate instrument manipulation, then adaptability is improved, but sealing contact is lost
Solution Approach 1:
The arcuate seal members are designed with dynamic characteristics that allow them to flex and move radially as the instrument valve housing moves off-center. This dynamic design enables the seals to maintain continuous contact with the housing surfaces during radial and off-centered movements, accommodating instrument manipulation while preserving sealing integrity.
Solution Approach 2:
The seal assembly utilizes changes in geometric parameters (arcuate shapes and orientations) to adapt to radial movements. As the housing moves, the arcuate seal members change their engagement parameters with the housing surfaces, maintaining optimal sealing contact throughout the range of motion and ensuring reliable sealing during instrument manipulation.
Data Source
AI summary
An access assembly includes an instrument valve housing and a valve assembly disposed within the instrument valve housing. The instrument valve housing includes upper and lower housing sections. The valve assembly includes a centering mechanism, a seal assembly, and a guard assembly. The centering mechanism is configured to bias the valve assembly towards a generally centered position within the instrument valve housing. The centering mechanism includes a base seal member having an annular base and a flange portion. The flange portion includes an arcuate portion configured to adjustably engage first and second surfaces of the instrument valve housing in a sealing relation. The seal assembly is attachable to the centering mechanism. The seal assembly is configured to engage a surgical instrument inserted into the access assembly in a sealing relation. The guard assembly is attachable to the centering mechanism.