Metal Washer Fixation for High-Pressure Fuel Sealing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Highly pressurized fuel systems face unreliable sealing due to increasing hardness of fuel rails, as conventional metal-to-metal deformation seals are no longer effective, and elastomeric or polymer seals lack sufficient strength and durability.
Innovation Solution
A metal washer is elastically deformed and fixed within a pocketed port of a pressure sensor, using a frustoconically shaped insertion tool to ensure a reliable, high-pressure seal without plastic deformation, utilizing a malleable material softer than the fuel rail and pressure sensor, and a mechanical press to securely fasten the washer in place.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional metal-to-metal deformation sealing is used, then the sealing structure is simple, but the seal reliability deteriorates due to increasing fuel rail hardness
Solution Approach 1:
A metal washer is introduced as an intermediary sealing element between the fuel rail and pressure sensor port. The washer is elastically deformed during installation to expand and seal against the port, providing reliable sealing without requiring deformation of the hard fuel rail material.
Solution Approach 2:
The washer undergoes elastic deformation parameter changes during installation - it is compressed radially to reduce its diameter, then when released, it expands elastically to seal against the port. This controlled parameter change enables reliable sealing while accommodating the increased hardness of fuel rails.
2Strength
If elastomeric or polymer seals are used, then the sealing structure is simple, but the material strength and durability are insufficient for high pressure applications
Solution Approach 1:
The solution uses a metal washer (typically stainless steel) as the sealing element, combining the strength and durability of metal with the elastic deformation capability needed for sealing. This metal-based composite approach provides both the required strength for high-pressure applications and the flexibility for elastic sealing.
3Reliability
If soft metal gaskets with wedge shaped sealing edges are used, then sealing can be achieved, but the device complexity increases due to required support frames and positioning structures
Solution Approach 1:
The complex support frames and positioning structures are removed from the design. The washer is designed to be self-positioning and self-retaining through elastic deformation, eliminating the need for additional support structures while maintaining reliable sealing.
Solution Approach 2:
The washer performs multiple functions autonomously: it seals against the port through elastic expansion, positions itself within the port, and retains itself without additional fasteners. This self-service capability eliminates the need for complex support frames and positioning structures.
4Reliability
If the washer is added just prior to connecting the pressure sensor to the fuel rail, then the sealing structure is simple, but the risk of washer disruption during transportation increases
Solution Approach 1:
The washer is pre-installed and secured to the pressure sensor port before transportation. Through elastic deformation and expansion, it is firmly retained in place, eliminating the risk of disruption during handling and transport while ensuring the sealing surface is ready for connection.
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
This method provides a robust, reliable sealing structure capable of withstanding high pressures (up to 2700 bar) with minimal deformation and wear, ensuring a consistent seal during assembly and transportation, reducing the risk of incorrect washer installation and maintaining seal integrity.
Implementation Method 1
The washer is elastically deformed while being driven into the annular recess, such that the washer takes on a round shape with a diameter that is equal to or less than the inner diameter of the annular recess
Implementation Method 2
Upon release, the washer will attempt to expand back into its original shape, but will be fixated against the inner wall of the annular recess by a retention force resulting from washer expansion and contact with the recess wall
Implementation Method 3
The washer may be elastically deformed by being pressed toward the annular recess through a (frusto-)conically shaped surface of an insertion tool
Data Source
AI summary
Assembly systems and methods are provided for elastically deforming a non-circularly shaped washer while driving the washer through an insertion tool into a workpiece, such as a pressure sensor, having a correspondingly shaped recess with an inner wall diameter less than a maximum radial dimension of the non-circular washer. The washer is released from radial compression into the recess so as to permit the washer to become fixated against the inner wall of the recess by a retention force. The fixated washer has a height greater than a height of the recess inner wall, and may serve as a deformable sealing element between the workpiece and other components.