Hybrid inflator with temporary gas generator throttle

摘要

A dual stage hybrid inflation device includes a first stage gas source (12) comprising a liquefied gas stored in a first stage pressure vessel (16) and a second stage gas source (14) comprising a gas generator (36) having a gas output (42) directed into the first stage pressure vessel. The gas generator is isolated from the first stage pressure vessel by a frangible diaphragm (38) that ruptures when the pressure in the gas generator exceeds the pressure in the first stage pressure vessel by a predetermined amount. The gas generator is also isolated from the first stage pressure vessel (16) by an eroding nozzle (50) that temporarily restricts the flow of gas from the gas generator to the first stage pressure vessel after the frangible diaphragm (38) ruptures. The eroding nozzle (50) initially restricts the flow of gas from the gas generator (36) to the first stage pressure vessel (16) to prevent a sudden pressure drop in the gas generator that would cause the pyrotechnic gas generating material to self extinguish. The nozzle (50) then erodes away to allow an unrestricted flow of combustion products from the gas generator (36) to the first stage pressure vessel (16).