Side Airbag Cushion Layout to Avoid Shoulder Interference

Solution Overview

Problem

Conventional airbags interfere with the occupant's shoulder during expansion and deployment due to the design covering nearly the entire cushion above the torso, leading to potential interference with the shoulder.

Innovation Solution

The airbag design includes a notched section between the first and second cushions, non-expandable sections, and a duct section for communication, allowing the airbag to expand and deploy without interfering with the shoulder, and includes a front protecting section to cover the front of the head.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Area of stationary object

If the airbag is designed to cover nearly the entire cushion above the torso, then head protection coverage is improved, but interference with the occupant's shoulder during expansion and deployment occurs

Engineering Contradiction:

Improvecoverage area of airbagVSAvoidinterference with shoulder

Core Design Contradiction:

Area of stationary objectVSObject-affected harmful factors

Solution Approach 1:

The airbag is divided into multiple cushions (first cushion, second cushion, third cushion) with distinct functional regions. The notched section creates a segmentation between the first and second cushions, allowing the second cushion to expand without interfering with the shoulder while the first cushion provides head protection.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the airbag are assigned different properties: the first cushion is designed for head protection with higher expansion, while the notched section creates a localized gap to avoid shoulder interference. The second cushion has restricted expansion in the shoulder region but maintains protection capability in other areas.

Inventive Principle:

Principle #3Local quality

2Reliability

If a second cushion is connected to the lower side of the first cushion for side head protection, then side head protection is improved, but interference with the shoulder during expansion and deployment occurs

Engineering Contradiction:

Improveside head protectionVSAvoidinterference with shoulder

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The airbag is divided into multiple cushions (first cushion, second cushion, third cushion) with distinct functional regions. The notched section creates a segmentation between the first and second cushions, allowing the second cushion to expand without interfering with the shoulder while the first cushion provides head protection.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the airbag are assigned different properties: the first cushion is designed for head protection with higher expansion, while the notched section creates a localized gap to avoid shoulder interference. The second cushion has restricted expansion in the shoulder region but maintains protection capability in other areas.

Inventive Principle:

Principle #3Local quality

3Reliability

If the airbag expands and deploys to cover the head comprehensively, then head protection is improved, but deployment time is increased

Engineering Contradiction:

Improvehead protectionVSAvoiddeployment time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The notched section is pre-formed in the airbag structure before deployment. This preliminary design feature allows the second cushion to expand into the predetermined gap space without resistance, enabling faster deployment compared to a fully continuous airbag structure that would require time to create expansion pathways.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The airbag is divided into multiple cushions (first cushion, second cushion, third cushion) with distinct functional regions. The notched section creates a segmentation between the first and second cushions, allowing the second cushion to expand without interfering with the shoulder while the first cushion provides head protection.

Inventive Principle:

Principle #1Segmentation

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 design suppresses interference with the shoulder during expansion and deployment, enabling smooth expansion and deployment, providing comprehensive protection for the head and torso, and allowing early restraint of the occupant.

Implementation Method 1

an inflator that supplies gas to the airbag

Methodology Applied

Scientific EffectGas expansion:

Data Source

PatentEP4219247B1Airbag device

Publication Date: 2025.10.22 AUTOLIV DEV AB

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Figure 5

AI summary

An airbag device including an airbag having a first cushion for protecting the side of the head of an occupant and a second cushion connected to the lower side thereof, wherein in order to suppress interference of the airbag with the shoulder of the occupant during the expansion and deployment process, the airbag device 10 includes: an airbag 11 for protecting the occupant 5 seated in the seat 1 of a vehicle, and an inflator 12 that injects gas supplied to the airbag 11, the airbag 11 in the expansion completed state where expansion and deployment are complete includes: the first cushion 21 that covers at least the side of the head of the occupant 5, and a second cushion 22 connected to the rear section of the first cushion 21 at a height near the shoulder of the occupant 5 which extends downward from this connecting point, and in the expansion completed state, the notched section 24 is formed extending from the front towards the rear in between the first cushion 21 and the second cushion 22.