Airbag Roll-Folding Method for Space-Efficient Deployment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing methods for folding airbags are inefficient in terms of space utilization and reproducibility, particularly for steering wheel airbags, which affects their deployment characteristics and requires complex folding techniques.
Innovation Solution
A method involving roll-folding the airbag into an elongate shape with the gas generator or airbag-retaining metal sheet positioned in the central third, allowing end portions to project and fold outward around the generator, optimizing space usage and facilitating rapid deployment by minimizing resistance during inflation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If the airbag is folded using traditional zigzag folding methods, then the folding process is relatively simple, but the space utilization is poor and deployment characteristics are compromised
Solution Approach 1:
The airbag is divided into multiple folding zones with different folding patterns. The first folding zone uses parallel zigzag folding to create an elongate package, while the second folding zone uses wave-shaped folding at the ends. This segmentation allows each zone to serve a specific function in optimizing space utilization while maintaining manageable folding complexity.
Solution Approach 2:
The airbag package is transformed from a linear elongate shape into a three-dimensional configuration by folding the ends in wave shapes and forcing them radially toward the gas generator. This dimensional transformation enables better space utilization by exploiting radial space around the gas generator rather than simply compressing the linear package.
2Manufacturing precision
If the airbag is folded to minimize positioning tolerances, then deployment precision is improved, but the folding process becomes more demanding and time-consuming
Solution Approach 1:
The airbag is pre-folded into an elongate package using parallel zigzag folding before the final assembly with the gas generator. This preliminary folding action establishes a consistent base configuration that simplifies subsequent steps and ensures reproducible positioning, reducing the time and complexity of achieving precise deployment characteristics.
Solution Approach 2:
Different folding methods are applied to different parts of the airbag based on their specific requirements. The central portion uses parallel zigzag folding for consistent elongate packaging, while the end portions use wave-shaped folding to achieve radial compression. This localized approach optimizes both reproducibility and efficiency for each specific region.
3Volume of moving object
If the airbag ends are folded inwards toward the gas generator, then space is saved, but resistance during deployment increases
Solution Approach 1:
Instead of folding the airbag ends inwards toward the center, the invention folds them outwards in wave shapes and then forces them radially toward the gas generator from the outside. This inverted approach allows the airbag to be compact while maintaining outward-facing folds that reduce deployment resistance by allowing smoother expansion during inflation.
Data Source
AI summary
A method for folding an airbag includes folding the airbag into an elongate state at least partially by roll-folding. The method also includes inserting a gas generator and/or an airbag-retaining metal sheet into the airbag. The gas generator and/or the airbag-retaining metal sheet is/are located in the central third of the airbag folded in elongate shape so that two end portions of the airbag project from the gas generator and/or from the airbag-retaining metal sheet. The method also includes guiding the airbag end portions around the outer circumference of the gas generator and/or of the airbag-retaining metal sheet in opposite directions toward each other up to a folding zone in which the end portions of the airbag at least almost contact each other. The method further includes folding over the end portions of the airbag from the folding zone outwards and guiding the airbag end portions in the opposite direction around the outer circumference of the gas generator and/or of the airbag-retaining metal sheet and around internal parts of the airbag end portions located thereon for forming external parts.