Patent ID: 6889614

Claim:
An air bag inflator comprising a housing having a combustion chamber therein and at least one port for expelling combustion gas from said combustion chamber; an initiator mounted on said housing for introducing a combustion gas into said combustion chamber; an injection piston slidably mounted in said combustion chamber of said housing for movement between an initial position and a second position in response to the introduction of a combustion gas into said combustion chamber from said initiator, said piston including a circumferential skirt defining a propellant chamber therein for containing a charge of liquid propellant therein, at least one nozzle communicating said propellant chamber with said combustion chamber to deliver liquid propellant thereto, and means for releasably closing said nozzle to prevent communication between said propellant chamber and said combustion chamber; a plug mounted in said housing coaxially of said piston to slidably receive said skirt of said piston; and a pump piston mounted in abutment with one end of said plug and slidably receiving said skirt of said injection piston thereon.