Airbag Diffuser Gas Deflecting Elements
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing airbag diffusers inadequately swirl and deflect gas flows, leading to direct pressure waves and hot gas impingement on the airbag fabric, necessitating additional protective layers.
Innovation Solution
Incorporating gas deflecting elements such as projections, recesses, or slits on the diffuser's outer wall to influence and swirl the gas flow, preventing direct impingement and ensuring uniform pressure distribution within the airbag by deflecting and cooling the gas.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If gas deflecting elements are added to the diffusor, then the swirling and deflection of gas flow is improved, but the device complexity increases
Solution Approach 1:
The diffusor wall is designed with a porous structure containing multiple through-going channels. The gas flow is deflected and swirled by passing through these channels, achieving protection of the airbag fabric without requiring additional complex deflecting elements. The porous structure itself performs the flow control function.
Solution Approach 2:
The solution transitions from a two-dimensional surface approach (adding deflecting elements on the surface) to a three-dimensional volumetric approach (creating through-going channels within the wall thickness). This allows the gas flow to be influenced throughout the volume of the diffusor wall, achieving better flow control with a more integrated structure.
2Object-affected harmful factors
If additional protective layers are added to protect airbag fabric, then the protection against hot gas is improved, but the device complexity and cost increase
Solution Approach 1:
The invention extracts the flow control function from separate protective layers and integrates it into the diffusor wall structure itself. The porous channels within the diffusor perform the flow deflection and swirling that would otherwise require additional protective components, simplifying the overall structure.
Solution Approach 2:
The diffusor wall is designed to perform multiple functions simultaneously: it serves as the structural boundary of the diffusor, provides flow control through its porous channels, and protects the airbag fabric by deflecting hot gas. This multi-functionality eliminates the need for separate protective layers.
3Productivity
If the diffusor is fully opened upon activation, then the gas discharge capability is improved, but the protection of airbag fabric against direct flow is reduced
Solution Approach 1:
The diffusor wall is designed with non-uniform porous structure where different regions have different channel densities and orientations. This allows localized control of gas flow in different areas, achieving both high discharge capability and fabric protection through spatially varying flow patterns.
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 effectively swirls and deflects gas flows, reducing pressure wave impact on the airbag fabric, achieving uniform pressure increase and cooling, thus eliminating the need for additional protective layers.
Implementation Method 1
gas deflecting elements are provided for influencing the discharge direction of the gas exiting the inflator
Implementation Method 2
the gas flow is deflected away from the airbag fabric and is additionally swirled
Implementation Method 3
They form an uneven reflection surface at the inside of the diffusor by which non-directed reflection of the gas flow takes place
Implementation Method 4
the gas is cooled by mixing before it impinges on the airbag fabric
Implementation Method 5
the outer wall has a gap edge substantially extending in the longitudinal direction and is bent open along said gap edge upon activation of the inflator
Data Source
AI summary
In a diffusor (14) for an inflator (10) of an airbag module including an outer wall (16) that encloses the inflator (10) at least in a discharge area (12) in the circumferential direction, wherein the outer wall (16) has a gap edge (18) extending substantially in the longitudinal direction (L) and is bent open along said gap edge (18) upon activation of the inflator (10) and a discharge direction for the gas is defined, it is provided that gas deflecting elements (24, 26) which influence the discharge direction of the gas discharged from the inflator (10) in the bent-open state of the diffusor (14) are provided at the outer wall (16).