Dual stage inflator

An inflator for inflating an airbag comprising:

• a housing having an axial centerline and comprising a first housing portion with a diameter d1, said first housing portion defining a first chamber, said housing further comprising a second housing portion with a diameter d2, said second housing portion defining a second chamber;
• a gas generant disposed in said first and second chambers;
• a first ignition unit for use in combusting said gas generant disposed in said first chamber;
• a second ignition unit for use in combusting said gas generant disposed in said second chamber;
• a barrier extending perpendicular to the axis of the inflator and separating the first and second chambers;
• a first ignition enhancer tube disposed in said first chamber, a portion of said first ignition unit being located within said first ignition enhancer tube, said first ignition enhancer tube having at least one outlet defined therein said first ignition enhancer tube capable of holding an ignition enhancer such that when said first ignition unit ignites, said ignition enhancer combusts and exits through said outlet and then reacts with said gas generant;
• a second ignition enhancer tube disposed in said second chamber, a portion of said second ignition unit being located within said second ignition enhancer tube, said second ignition enhancer tube having at least one outlet defined therein, said second ignition enhancer tube capable of holding an ignition enhancer such that when said second ignition unit ignites, said ignition enhancer combusts and exits through said outlet and then reacts with said gas generant;
• and
• wherein said barrier extending perpendicular to the axis of the inflator comprises a first divider plate connected to said first housing portion and a second divider plate connected to said second housing portion, said second divider plate having a main body having a circumferentially extending flange portion;
• inner and outer annular ribs integrally formed with said main body and forming cavities thereunder;
• and a circumferentially extending rim surrounding said circumferentially extending flange portion such that said circumferentially extending rim contacts an interior wall of said second housing portion.

An inflator for an automotive airbag comprising:

• a first housing portion defining a first chamber, said first housing portion having a first divider plate attached thereto;
• a second housing portion defining a second chamber, said second housing portion having a second divider plate attached thereto, said first and second divider plates forming a separating wall between said first and second housing portions, said first divider plate comprising a main body having a circumferentially extending flange portion, inner and outer annular ribs integrally formed with said main body and forming cavities thereunder, and a circumferentially extending rim surrounding said circumferentially extending flange portion such that the circumferentially extending rim contacts an interior wall of said first housing portion during assembly, said second divider plate further comprising a main body, inner and outer annular ribs integrally formed with said main body and forming cavities thereunder, and a circumferentially extending flange portion contacting said first divider plate and said second housing portion;
• a maximum diameter and a height of the exterior of the inflator forming a ratio of Dmax/h, said ratio Dmax/h ranging from substantially 1.00 to 3.00;
• a gas generant disposed in said first and second chambers;
• a first ignition unit disposed in said first chamber;
• a second ignition unit disposed in said second chamber;
• a plurality of gas exit ports defined in said first housing portion and said second housing portion;
• a first filter radially spaced from said first ignition unit and disposed between said gas generant and said plurality of gas exit ports of said first housing portion;
• a second filter radially spaced from said second ignition unit and disposed between said gas generant and said plurality of gas exit ports of said second housing portion;
• a first ignition enhancer tube disposed in said first chamber, a portion of said first ignition unit being located within said first ignition enhancer tube, said first ignition enhancer tube having a plurality of openings defined therein, said first ignition enhancer tube capable of holding an ignition enhancer;
• a second ignition enhancer tube disposed in said second chamber, a portion of said second ignition unit being, located within said second ignition enhancer tube, said second ignition enhancer tube having a plurality of openings defined therein, said second ignition enhancer tube capable of holding an ignition enhancer;
• and
• wherein said first and second ignition units each includes an igniter retainer attached to a respective housing portion and an igniter attached to said igniter retainer, wherein activation of said igniters causes said gas generant to combust, such that when said igniters ignite, said ignition enhancers combust and exit through said plurality of openings and then react with said gas generant, whereby gas resulting from combustion of said gas generant is not forced to turn at an angle greater than or equal to ninety degrees before exiting said plurality of gas exit ports.