Compressible Seal with PTFE Coating for Hermetic Housing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Hermetically sealed housings in aerospace engineering face challenges with corrosion, tightness, and water vapor permeation, as existing sealing technologies like fluorosilicone rubber and metal C-rings are prone to corrosion, have low tear resistance, and offer inadequate protection against gases and complex shapes.
Innovation Solution
A housing arrangement with a compressible seal inserted into a milled recess, providing defined compression and improved handling, along with a non-conductive surface coating for corrosion protection and conductive coatings for bonding, ensuring gas-tightness and reduced corrosion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If fluorosilicone rubber seals are used in hermetic housings, then temperature resistance and fuel/oil resistance are improved, but tear resistance is low and friction is high
Solution Approach 1:
The patent uses a composite sealing structure combining a fluorosilicone rubber seal element with a PTFE (polytetrafluoroethylene) coating layer. The PTFE coating provides low friction and high wear resistance, while the fluorosilicone rubber base material maintains temperature resistance and fuel/oil resistance. This composite approach resolves the contradiction by adding protective properties without sacrificing the original material's thermal and chemical resistance.
2Reliability
If O-ring seals are compressed to achieve tightness, then sealing performance is improved, but excessive compression causes damage and failure
Solution Approach 1:
The patent modifies the compression parameters by introducing a PTFE coating layer that acts as a stress-distributing interface. This coating layer reduces the effective compression stress on the O-ring while maintaining the sealing force, allowing the seal to achieve tightness without excessive compression that would cause damage. The parameter change is in the distribution and magnitude of compressive stress.
3Object-affected harmful factors
If non-conductive corrosion protection coating is applied to the housing surface, then corrosion resistance is improved, but electrical conductivity and bonding performance deteriorate
Solution Approach 1:
The patent applies corrosion protection locally through a PTFE coating that is selectively positioned in specific areas where corrosion risk exists but electrical conductivity is not critical. This localized application maintains overall electrical conductivity and bonding performance while providing corrosion protection where most needed, resolving the contradiction between universal corrosion protection and electrical functionality.
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 significantly reduces corrosion and improves tightness and water vapor permeation, maintaining electromagnetic compatibility and bonding performance under extreme conditions.
Implementation Method 1
at least one seal (12, 14) made of a compressible seal which has an elastic component, inserted into an opening (16, 18) consisting of a milled recess provided in the housing (10)
Implementation Method 2
a non-conductive surface coating (26) for corrosion protection is applied on the environmental side to the surface (24) of the housing (10) up to the opening (16)
Data Source
Figure 1
Figure 2
AI summary
The arrangement has seal (12) that is provided with a compressible material having an elastic portion, and is positioned in a milled portion (16). The milled portion is provided in a plug flange (22) of the plug-in connector (20). The seal of ring shaped is press-fitted into the milled portion. An independent claim is included for a seal assembly for sealing a housing arrangement.