Patent ID: 6169947
Filing Date: 2001-01-02
Classification: B60R

Abstract:
A vehicle occupant protection system for detecting an impact to introduce a gas from an inflator into an air bag to inflate the air bag in a motor vehicle, comprising: a detector for detecting an impact; an impact calculator for calculating a magnitude of the impact from an output signal from said detector; a first switch for being turned on when a seat belt in the motor vehicle is not fastened and being turned off when the seat belt is fastened; a second switch for being turned off when the seat belt is not fastened and being turned on when the seat belt is fastened; a fastened status detector for detecting whether the seat belt is fastened or not, based on output signals from said first switch and said second switch; a selector for selecting either an impact decision level when the seat belt is not fastened or an impact decision level when the seat belt is fastened, based on an output signal from said fastened status detector; a comparator for comparing the magnitude of the impact calculated by said impact calculator with the impact decision level selected by said selector, and outputting an activating signal when the calculated magnitude of the impact is greater than the selected impact decision level; and an activator for activating the insulator to introduce a gas into the air bag in response to the activating signal from said comparator; said selector having means for selecting the impact decision level when the seat belt is not fastened if both said first switch and said second switch are turned on or off.