Welded Feed-Through Connector Assembly for Implantable Pulse Generators
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current connectors for implantable pulse generators (IPGs) face limitations, including insufficient support for devices with 24-26 contacts, larger feed-through wire pitches, and lack of stress relief, which complicates electrical connections and assembly processes, especially when using dissimilar materials.
Innovation Solution
A welded feed-through connector assembly with temporary connecting structures allows for flexible installation and stress minimization between the header and hermetic enclosure, enabling efficient assembly and long-term durability by using laser welding or resistance welding for connections between platinum and other materials like MP35N or SS 316LVM.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If hand routed feed through wires are used to connect directly to the lead connection stack, then the FT pitch can be larger (approximately 0.075 inches), but the device cannot support high contact counts (24-26 contacts) and lacks stress relief
Solution Approach 1:
The connector assembly is divided into modular components: a header portion with conducting pins, a hermetic enclosure, and a lead connection stack with contact blocks. This segmentation allows each component to be optimized independently - the header can accommodate high-density pins while the connection stack provides flexible wiring pathways, enabling support for 24-26 contacts with reduced pitch requirements.
Solution Approach 2:
The lead connection stack is positioned within the hermetic enclosure, and the header portion is connected to the enclosure. This nested arrangement allows the FT wires to be routed through the enclosure space, providing stress relief pathways while maintaining compact overall dimensions and supporting high contact counts without increasing external device size.
2Reliability
If dissimilar materials (platinum and MP35N or SS 316LVM) are connected, then electrical conductivity is achieved, but welding complexity and stress resistance are reduced
Solution Approach 1:
The connector assembly introduces intermediate connection points and transition structures between dissimilar materials. The header portion with conducting pins serves as an intermediary that can be welded to the hermetic enclosure using materials compatible with both platinum and MP35N or SS 316LVM, simplifying the welding process while maintaining electrical continuity across dissimilar material interfaces.
Solution Approach 2:
The design allows for parameter optimization in the welding process by separating the welding locations into distinct stages - welding the header to the enclosure, and welding the lead connection stack to the header. This enables adjustment of welding parameters (temperature, time, pressure) for each specific material interface, reducing overall welding complexity while ensuring reliable electrical connections.
3Adaptability or versatility
If the device size is reduced to accommodate more contacts, then contact density increases, but stress relief and assembly flexibility are compromised
Solution Approach 1:
The lead connection stack provides three-dimensional routing pathways for FT wires within the hermetic enclosure, allowing stress relief in multiple directions. This vertical and lateral dimensionality enables high contact density on the header face while providing adequate space for wire routing and stress distribution throughout the assembly volume, preventing stress concentration that would compromise strength.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution provides a compact, durable, and stress-resistant electrical connection that supports higher contact counts in a smaller device configuration, facilitating easier assembly and ensuring reliable electrical continuity across multiple lead ports.
Implementation Method 1
enabling efficient assembly and long-term durability by using laser welding or resistance welding for connections between platinum and other materials like MP35N or SS 316LVM
Implementation Method 2
enabling efficient assembly and long-term durability by using laser welding or resistance welding for connections between platinum and other materials like MP35N or SS 316LVM
Data Source
AI summary
A connector assembly, and its method of assembly, for use in a medical device for connecting an IPG to a connector assembly for connecting the IPG to a relatively large plurality of electrodes that can support 24 or more stimulation channels for stimulating one or more stimulation regions of a patient. Also the IPG and the stimulation system and the stimulation therapy utilizing the connector assembly.