Airbag Curvature via Differential Thread Orientation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing airbag designs face challenges in achieving the desired curvature for optimal protection of vehicle occupants without increasing the airbag volume or requiring larger gas generators, which can compromise space efficiency and increase manufacturing costs.
Innovation Solution
The airbag features two layers with differently aligned threads, allowing for curvature when inflated by varying the angles of the threads with respect to the longitudinal direction, enabling different expansion and compression behaviors that result in a curved shape without additional cuts or tethers, and can be designed to support the head and thorax area effectively.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the gas bag volume is increased to position it closer to the vehicle occupant's head, then the protective effect is improved, but the space occupied when folded increases and a larger gas generator is required
Solution Approach 1:
The patent changes the geometric parameters of the fabric cuts, specifically the shape and orientation of the longitudinal and transverse seams, to create curvature in the inflated state without increasing the folded volume or gas generator size
Solution Approach 2:
The patent applies curvature to the gas bag by designing fabric cuts with specific seam orientations that cause the inflated airbag to form a curved shape, allowing it to reach closer to the occupant's head while maintaining compact folded dimensions
2Shape
If additional tethers or ruffled seams are used to curve the gas bag, then the positioning is improved, but the manufacturing complexity and expense increase
Solution Approach 1:
The patent achieves curvature by changing the parameters of the fabric cuts themselves, specifically the angles and orientations of the seams, rather than adding separate curvature-inducing components like tethers or ruffles
Solution Approach 2:
The patent extracts the curvature function from separate components (tethers, ruffled seams) and integrates it directly into the fabric cut design, eliminating the need for additional manufacturing steps and components
3Reliability
If a larger gas generator is used to fill a larger volume, then the protective effect is improved, but the space available for the airbag module decreases
Solution Approach 1:
The patent changes the geometric parameters of the fabric cuts to create an inflated shape that reaches closer to the occupant's head without requiring a larger gas volume, thereby maintaining a compact gas generator size and preserving module space
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 solution allows for a compact airbag design that achieves the desired curvature at high internal pressures, providing effective protection without the need for larger volumes or additional components, thus optimizing space usage and manufacturing simplicity.
Implementation Method 1
When the airbag is inflated, the fabric of the first and second airbag layers in the elongated section is more heavily stressed transversely to the longitudinal direction of the elongated section than along the longitudinal direction of the elongated section. Since the threads of the two airbag layers enclose a different angle with the longitudinal direction of the elongated section, the relative arrangement of the threads can change to different extents, leading to different expansion and compression behavior and thus to a curvature of the airbag.
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
The invention relates to an airbag (2) which can be inflated in order to protect a vehicle occupant, said airbag comprising: a first airbag layer (4a) and a second airbag layer (4b), wherein a first fabric cut-out forms the first airbag layer (4a) and a second fabric cut-out forms the second airbag layer (4b), wherein the first fabric cut-out and the second fabric cut-out are each woven from threads (16), wherein the airbag (2) has at least one elongate portion (18) which extends along a longitudinal direction (L1) and which is formed at least by a portion of the first airbag layer (4a) and at least a portion of the second airbag layer (4b). The airbag is characterized in that, when the airbag is in the resting state, the threads (16) of the first airbag layer (4a) and the threads (16) of the second airbag layer (4b) are oriented relative to each other in such a way that the threads (16) of the first airbag layer (4a) form an angle with the longitudinal direction (L1) that is different from that formed by the threads (16) of the second airbag layer (4b), the angles being selected such that the airbag (2) has a curvature in the direction of one of the two airbag layers (4a, 4b) in the inflated state.