Syringe Needle Adapter Sealing for Long-Term Closure Integrity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing connectors for prefilled syringes with staked needles fail to maintain container closure integrity during long-term storage, particularly at extreme temperatures and high humidity, leading to leakage and contamination.
Innovation Solution
A syringe system with an adapter that connects the needle to the syringe barrel, featuring a pull-off force of 1 N to 500 N and cone breakage force of 1 N or more and/or 400 N or less, ensuring secure attachment and sealing through a click mechanism and resilient sealing member, using materials like polypropylene and elastomers to compensate for tolerances and prevent damage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If existing connectors are used for fixing the needle to the syringe barrel, then the assembly process is simple, but the container closure integrity deteriorates during long-term storage at extreme temperatures and high humidity
Solution Approach 1:
The adapter is designed with a resilient sealing member that proactively compensates for thermal expansion and contraction of the cone during temperature cycling. The resilient material absorbs dimensional changes before they can compromise the seal, preventing leakage and contamination during long-term storage at extreme temperatures and high humidity.
Solution Approach 2:
The sealing interface transitions from a rigid mechanical connection to a compliant seal that adapts its physical properties. The resilient sealing member changes its dimensional parameters in response to temperature and humidity conditions, maintaining optimal contact pressure and seal geometry throughout storage duration to preserve container closure integrity.
2Reliability
If the adapter exerts sufficient pressure to seal the contacting surfaces, then the container closure integrity improves, but the cone may break resulting in reduced integrity
Solution Approach 1:
The resilient sealing member acts as an intermediary between the adapter and the cone. It transmits the necessary sealing pressure to the contacting surfaces while absorbing and distributing the load to prevent stress concentration on the cone. This mediator protects the cone from breakage while maintaining adequate seal pressure for container closure integrity.
Solution Approach 2:
The resilient sealing member functions as a flexible element that deforms under compression to create the seal. Its flexibility allows it to conform to surface variations and distribute pressure evenly, achieving reliable sealing without exerting excessive point loads that could fracture the cone structure during long-term storage.
3Force
If the adapter is tightly locked to the syringe barrel, then the pull-off force increases preventing accidental removal, but the risk of cone breakage increases
Solution Approach 1:
The resilient sealing member serves as a flexible element that provides friction grip between the adapter and syringe barrel. The compliance of the resilient material increases the coefficient of friction at the interface, generating high pull-off force through normal contact pressure without requiring excessive clamping force that could fracture the cone.
Solution Approach 2:
The frictional locking mechanism relies on changing the normal force parameter applied by the resilient sealing member. By optimizing the compression set and elastic properties of the resilient material, the system achieves maximum static friction force for preventing accidental adapter removal while keeping the applied load below the cone's fracture threshold.
Data Source
AI summary
Disclosed is a system for long-term storage of a pharmaceutical composition particularly comprising a syringe. The system comprises an adapter for fixing a needle to the syringe barrel providing improved container closure integrity.