Abstract: A projectile accelerating pulsed gas source comprises a structure including a high voltage electrode for establishing axial electrical discharges in axial gaps behind an outlet where the projectile is located. Plasma flows at right angles to the discharges into a propellant that is converted into a high pressure component of the gas pulse. The gaps are arranged so that after the projectile moves away from its initial position, power applied to the plasma via gaps close to the outlet is greater than power applied to the plasma via gaps farther from the outlet. The gaps are arranged so power applied to the plasma is substantially the same in the discharges when plasma is initially produced. The gaps include walls that are eroded differently by the discharges so gap walls close to the outlet erode faster than gap walls farther from the outlet.

Abstract: An occupant passive restraint system for an automotive vehicle comprises an air bag and a pulsed pressure source in fluid flow relation with the air bag. The pulsed pressure source includes plural pulsed pressure sources sequentially energized in response to the deceleration sensor sensing a single crash impact. Each source includes plural chambers holding progressively larger masses of gas generant. The chambers are arranged so that each has an outlet coupled with the chamber having the next largest gas generant mass. The gas generant mass in each chamber is predominantly a non-explosive solid particulate material. The smallest chamber includes a fuse in contact with the generant. When a crash is sensed the fuse is supplied with a pulse having sufficient energy and duration to rupture the fuse and form a plasma discharge in the generant in the smallest chamber. The plasma discharge has sufficient energy to ignite the generant in the smallest chamber to a vapor.