How Early Vehicle Airbag Safety Systems Work

A 1968 patent describing an early vehicle safety system that uses a rapidly inflating confinement to protect passengers during a collision.

What it covers

The device functions as an occupant restraint system that remains collapsed during normal operation. Upon detecting an accident, it triggers an expansion process to deploy a confinement, which acts as a cushion. The patent details two primary methods for inflation: using a fluid reservoir with a zero-reaction diffuser to direct gas flow, or utilizing gas-generating chemical materials that ignite to fill the confinement instantly.

What it doesn't cover

• —Does not cover electronic crash sensors or modern accelerometer-based deployment logic
• —Does not cover multi-stage inflation systems that adjust pressure based on occupant size
• —Does not cover side-curtain or knee-based airbag configurations

The clever bit

The use of a zero-reaction diffuser allowed for the rapid movement of high-pressure gas without creating a massive physical recoil force that could damage the vehicle's dashboard structure during deployment.

Why it matters

This patent represents a foundational step in automotive safety technology. It helped transition the industry from reliance on basic seatbelts toward the active, automated restraint systems that are now standard in every passenger vehicle worldwide.

Real-world examples

• 1.Early automotive supplemental restraint systems (SRS)
• 2.Experimental 1970s vehicle safety prototypes