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.
Original patent title: “Safety device”
A 1968 patent describing an early vehicle safety system that uses a rapidly inflating confinement to protect passengers during a collision. Granted to Eaton Yale and Towne Inc in 1971 with 26 forward citations, and it is now in the public domain.
Key facts
Coverage
What does this patent actually cover?
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.
The gap
What does this patent NOT 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
These exclusions are unique to PatentBrief — derived from the actual claim language, not patent-office boilerplate.
What made this novel
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.
The Patent Drawing
Schematic visualization of the patent's claim structure. Hand-drawn diagrams in progress for each landmark patent.
Where you've seen this
Real-world examples
Early automotive supplemental restraint systems (SRS)
Experimental 1970s vehicle safety prototypes
Why it matters
The bigger picture
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.
Filed
November 21, 1968
Granted
January 5, 1971
Market context
Who's building on this
Companies in this space
Major automotive suppliers like Autoliv, ZF Friedrichshafen, and Joyson Safety Systems continue to refine the chemical and mechanical principles of rapid gas inflation established in early patents like this one.
Market impact
This technology laid the groundwork for the mandatory adoption of airbags in the 1990s. It triggered a shift in automotive design where safety became a primary competitive differentiator and a regulated requirement for all manufacturers.
Claim 1 — Plain English
What this patent 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.
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.
What it does not 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
Patent Journey
From filing to expiry
PatentBrief Score
Impact Score
Early stage
Citation count
29/40
Moderately cited
Claim breadth
0/20
Narrow claimsclaimsThe numbered statements at the end of a patent that legally define what the inventor owns.Read more →
Recency
0/20
Older than 20 years
Assignee scale
0/20
Independent or smaller assigneeassigneeThe entity that owns the patent — usually the inventor's employer or a company.Read more →
PatentBrief Impact Score — based on citation count, claim breadth, recency, and assignee scale. Not a legal assessment.
Heuristic Value Estimate
What this patent might be worth
$8K – $26K
Midpoint $16K · expired or expiring · industry ×0.9
Heuristic only — blends forward/backward citation counts, claim scope, time remaining, litigation history, and CPC-derived industry baseline. Real valuations need a professional appraisal.
Concepts involved
Citations
Patent lineage
Cite this patent
Berryman, C. O. (1971). How Early Vehicle Airbag Safety Systems Work (U.S. Patent No. 3,552,770). U.S. Patent and Trademark Office. https://patentbrief.org/patent/us/3552770/automotive-airbag-safety-device
Auto-generated from the patent record. Double-check author order and the issue date against the official USPTO document before submitting.
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Common Questions
Frequently Asked Questions
What does How Early Vehicle Airbag Safety Systems Work cover?
A 1968 patent describing an early vehicle safety system that uses a rapidly inflating confinement to protect passengers during a collision.
Who owns patent US 3552770?
Eaton Yale and Towne Inc owns this patent, granted in 1971.
When does this patent expire?
This patent has expired and is now in the public domain — anyone can use the invention freely.
What is patent US 3552770 cited by?
This patent has been cited by 26 later patents that build on its ideas.
What problem does this patent solve?
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.
What does this patent NOT cover?
Does not cover electronic crash sensors or modern accelerometer-based deployment logic
Patent monitoring