Rigid Plastic Connector Header for Implantable Medical Devices
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional connector headers for implantable medical devices, made from polyurethane, lack rigidity, leading to feedthrough failures due to stress from side-to-side deflection, while more rigid materials crack or craze, and the manufacturing process is time-consuming due to low temperature and pressure requirements.
Innovation Solution
The use of a housing made from a plastic material with a modulus of rigidity of 100 ksi or greater, such as polysulfone or polycarbonate, which is dimensionally stable and less prone to cracking, combined with methods like plasma treatment to improve adhesive bonding and minimize stress during manufacturing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If polyurethane housing is used for connector header, then the housing is flexible and does not crack or craze under stress, but the housing lacks rigidity and transfers stress to feedthrough pins causing failure
Solution Approach 1:
The patent changes the material parameter (modulus of rigidity) from polyurethane (26 ksi) to rigid plastic (100 ksi or greater), fundamentally altering the mechanical properties of the housing to simultaneously achieve crack resistance and stress protection for feedthrough pins
Solution Approach 2:
The patent employs a composite construction where a rigid plastic housing is combined with adhesive bonding and overmolding techniques, creating a multi-material system that distributes stress away from feedthrough pins while maintaining structural integrity
2Reliability
If more rigid polymeric materials are used for connector header housing, then the housing provides dimensional stability and prevents feedthrough failure, but the materials are prone to cracking and crazing
Solution Approach 1:
The patent identifies and applies the critical parameter threshold (modulus of rigidity ≥100 ksi) that distinguishes rigid plastics suitable for this application, changing the material selection criterion to resolve the contradiction between rigidity and crack resistance
Solution Approach 2:
The patent incorporates adhesive bonding layers and overmolding processes that act as cushioning elements, absorbing and distributing stresses before they can cause cracking or crazing in the rigid plastic housing
3Strength
If low temperature and pressure are used for over-molding liquid silicone rubber, then the polyurethane housing is not damaged, but the manufacturing process takes significant amount of time
Solution Approach 1:
The patent changes the temperature and pressure parameters used in over-molding, enabling higher processing conditions that reduce cycle time while the rigid plastic housing's inherent strength protects against damage from these elevated parameters
4Manufacturing precision
If rigid plastic material with modulus of 100 ksi or greater is used, then the housing is dimensionally stable and manufacturing tolerances are tighter, but the material requires different manufacturing conditions
Solution Approach 1:
The patent adjusts manufacturing parameters (temperature, pressure, adhesive application) to match the requirements of rigid plastic materials, transforming the ease of manufacture by optimizing the process for the selected material properties
Data Source
AI summary
A connector header includes a housing formed from a plastic material having a modulus of rigidity of 100 ksi or greater. The housing defines an opening for insertion of a lead. The connector header further includes a lead receptacle having an electrically conductive element. The electrically conductive element is operably couplable to a feedthrough of the implantable medical device. The lead receptacle is in communication with the opening and is disposed within the housing such that an electrical contact of the lead is electrically couplable to the conductive element of the receptacle when the lead is inserted into the receptacle.