Cool gas powers new inflators

A new inflator technology is helping to make protection from side-impact and rollover accidents a practical reality for passenger-vehicle occupants. Autoliv Side Hybrid-2 (ASH-2) ‘cool gas’ inflator is already part of side-impact safety systems in some of the newest models from GM and DaimlerChrysler, and will soon find its way into the offerings of other major automakers.

The patented ASH-2’s unique performance characteristics are based on the science of dissociation, rather than on classic combustion principles used in other inflators. Dissociation separates the gas into its nitrogen and oxygen components without generating high temperatures, and uses the energy that comes from breaking the bond between the nitrogen and oxygen to expand the gas.

Unlike conventional inflators, which generate relatively hotter gases, the ‘cool-gas’ technology prevents volume loss caused by gases that contract as their temperature drops. This is especially crucial for systems providing rollover protection, where the side curtain must remain fully inflated for the entire rollover event which can take up to several seconds.

Manufacturing considerations also favour the ASH-2. The new inflator has 44% fewer parts and less than half the welds of the company’s previous models, making it simple to manufacture and robust in design.

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