Patent ID: 6072246
Filing Date: 2000-06-06
Classification: B60R

Abstract:
A method for triggering a passive occupant protection system for motor vehicles of the type including a plurality of electric ignition agents for respective safety devices protecting a person in the vehicle in the event of a hazardous impact, and a trigger circuit which provides each of the electric ignition agents with ignition energy via a respective trigger current which, in the event of a functional failure occurring in the on-board electric system of the motor vehicle, is generated as the discharge current of an autarchic capacitor; said method comprising the steps of: measuring the resistance value of each ignition agent whilst the motor vehicle is in operation, in order to define therefrom the ignition energy required for the ignition of the respective ignition agent; in the event of a functional failure of the on-board electric system, simultaneously applying the discharge current of the autarchic capacitor in parallel to each of the electric ignition agents while pulse-width modulating the respective trigger current for each ignition agent such that the defined ignition energy required for the respective ignition agent is preset by the respective pulse-to-pause ratio of the respective trigger current based on the respective measured resistance.