Pulsed pressure source particularly adapted for vehicle occupant air bag restraint systems

An occupant passive restraint system for an automotive vehicle having a battery comprising an air bag, means for sensing deceleration of the vehicle associated with a crash, a pulsed pressure source in fluid flow relation with the air bag, the pulsed pressure source including:

• plural chambers holding progressively larger masses of gas generates, said chambers being arranged so that each has an outlet coupled in fluid flow relation with the chamber having the next largest gas generant mass, the gas generant mass in each chamber being predominantly a non-explosive solid material, the smallest chamber including a metal element in contact with the generant therein and selectively connected to an electric source energized by said battery, the electric source responding to the deceleration sensing means for supplying a pulse having sufficient energy and duration to the element to cause the metal element to burst and form a plasma discharge having sufficient energy and pressure to the plasma discharge having sufficient energy and pressure to energize the generant in the smallest chamber to a vapor, the chambers and generants being arranged so that gas from each chamber sequentially flows into the chamber having the next largest gas generant mass to sequentially activate the generant mass in the next largest chamber, the gas from the chamber having the largest generant mass flowing into the air bag.

An occupant passive restraint system for an automotive vehicle having a battery comprising an air bag, means for sensing deceleration of the vehicle associated with a crash, a pulsed pressure source in fluid flow relation with the air bag, the pulsed pressure source including:

• means for generating separate pressure pulses at sequential time intervals in response to the deceleration means sensing a single impact of a crash, pressures from the sequentially generated pulses being combined to produce a flow for inflating the air bag, means for generating the separate pressure pulses including plural sources of pressure pulses, said sources being responsive to the crash sensing means to be sequentially activated, each of said sources of pressure pulses including plural chambers holding progressively larger masses of gas generants, said chambers being arranged so that each has an outlet coupled in fluid flow relation with the chamber having the next largest gas generant mass, the gas generant mass in each chamber being predominantly a non-explosive solid material, the smallest chamber including a metal element in contact with the generant therein and selectively connected to an electric source energized by said battery, the electric source responding to the deceleration sensing means for supplying a pulse having sufficient energy and duration to the element to cause the metal element to rupture and form a plasma discharge in the generant in the smallest chamber, the plasma discharge having sufficient energy and pressure to energize the generant in the smallest chamber to a vapor, the chambers and generants being arranged so that gas from each chamber sequentially flows into the chamber having the next largest gas generant mass to sequentially activate the generant mass in the next largest chamber, the gas from the chamber having the largest generant mass flowing into the air bag.