David D. Schroeder - Ogden UT
Clark C. Strong - Kaysville UT
Marcus T. Clark - Kaysville UT
Marvin F. Fleming - Los Altos CA
Samuel Hersh - Danville CA
Morton International, Inc. - Chicago IL
An inflator for an airbag system has a target mounted in the pressurized gas contained in the inflator. An ultrasonic transducer is mounted on an external surface of the inflator in alignment with the target. The transducer generates and receives reflected ultrasonic signals from the target. The time-of-flight of the signals which are dependent on the gas pressure are used to determine the gas pressure in the inflator. Temperature compensation is provided by fabricating the target of bimetallic material which changes the spacing of the target from the transducer with temperature or providing a temperature sensitive element, e. g. a thermocouple to electrically provide temperature compensation.