Gas generant

Abstract

The present invention includes a gas generator 10 that incorporates a gas generating composition 12 and a scavenging additive 16 in heterogeneous but vapor / gaseous communication with the gas generating composition 12. The scavenging additive retains moisture / contaminants typically evolving over time at relatively higher temperatures. The present invention further includes a gas generating system 180 incorporating the gas generator 10.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit of U.S. Provisional Application Ser. No. 60 / 722,168 filed on Sep. 30, 2005.TECHNICAL FIELD [0002] The present invention relates generally to gas generating systems, and to gas generant compositions employed in gas generator devices for automotive restraint systems, for example. BACKGROUND OF THE INVENTION [0003] The present invention relates to gas generant compositions that upon combustion produce a relatively small amount of solids and a relatively abundant amount of gas. It is an ongoing challenge to reduce the amount of solids and increase the amount of gas thereby decreasing the filtration requirements for an inflator. As a result, the filter may be either reduced in size or eliminated altogether thereby reducing the weight and / or size of the inflator. [0004] An equally important challenge is to manufacture gas generants that exhibit relatively low sensitivity with regard to impact, friction, or ...

AI Technical Summary

Benefits of technology

[0012] The use of certain additives, preferably zeolites such as molecular sieves, calcium sulfate (Drierite™), or calcium oxide can minimize, and in some cases eliminate contaminants occurring within the inflator over time. In particular, molecular sieves function to better retain moisture and other contaminants in the presence of relatively high temperatures such as 107 degrees Celsius, thereby ensuring predictable performance of associated inflators. Stated another way, molecular sieves retain moisture / contaminants at elevated temperatures at least as high as 107 degrees Celsius thereby facilitating consistent performance predictability of inflators incorporating one or more types of these additives.

Problems solved by technology

It is an ongoing challenge to reduce the amount of solids and increase the amount of gas thereby decreasing the filtration requirements for an inflator.

An equally important challenge is to manufacture gas generants that exhibit relatively low sensitivity with regard to impact, friction, or electrostatic discharge stimuli.

Yet another challenge with gas generant compositions that produce relatively small amounts of solids, sometimes known as “smokeless” compositions, is that hot all non-metallic constituents contribute to stable ballistic performance when subjected to environmental conditioning.

These extreme tests can cause many problems, ranging from failure to inflate the airbag to over-pressurization of the inflator leading to rupture.

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