Dual stage inflator

• US 20090288574A1
• Filed: 05/20/2008
• Published: 11/26/2009
• Est. Priority Date: 05/20/2008
• Status: Active Grant

• Current Assignee: Autoliv ASP Incorporated (Autoliv Incorporated), Autoliv Incorporated
• Original Assignee: Autoliv ASP Incorporated (Autoliv Incorporated)
• Inventors: Smith, Kevin R., Jackson, Scott A.
• Granted Patent: US 7,950,693 B2
• Time in Patent Office: Days
• US Class Current: 102/530
• CPC Class Codes: B60R 2021/2648 comprising a plurality of combustion chambers or sub-chambers
• CPC Class Codes: B60R 21/263 using a variable source, e.g. plural stage or controlled output hybrid inflators B60R21/272
• CPC Class Codes: B60R 21/2644 using only solid reacting substances, e.g. pellets, powder

Abstract

A dual stage inflator device including a housing defining first and second chamber each containing a quantity of gas generant material ignitable to produce combustion products. A divider plate, separating the first chamber from the second chamber, is disposed and fixed within the housing. The divider plate includes an opening to allow gas flow communication from the second chamber to the first chamber. A removable plug element is normally disposed in the divider plate opening to prevent gas flow communication between the first chamber and the second chamber when in a static state.

Claims

1. A dual stage inflator device comprising:

a housing, the housing at least in part defining a first chamber containing a quantity of a first gas generant material ignitable to produce first combustion products including a first inflation gas, the housing also at least in part defining a second chamber containing a quantity of a second gas generant material ignitable to produce second combustion products including a second inflation gas;

a divider plate disposed and fixed within the housing, the divider plate separating the first chamber from the second chamber, the divider plate including a first opening to allow gas flow communication from the second chamber to the first chamber; and

a plug element disposed in the first opening of the divider plate to prevent gas flow communication between the first chamber and the second chamber through the first opening in a static state.

2. The dual stage inflator device of claim 1 wherein the plug element is press fit secured within the first opening when said inflator device is in a static state.

3. The dual stage inflator device of claim 1 wherein the housing at least in part defining the first chamber includes a plurality of spaced apart gas exit ports to permit passage of first inflation gas from said inflator device.

4. The dual stage inflator device of claim 3 additionally comprising a filter element disposed within the first chamber adjacent the plurality of spaced apart gas exit ports for filtration of combustion products of the first chamber.

5. The dual stage inflator device of claim 3 wherein the spaced apart gas exit ports also permit passage of the second inflation gas from said inflator device.

6. The dual stage inflator device of claim 5 additionally comprising a filter element disposed within the first chamber adjacent the plurality of spaced apart gas exit ports for filtration of combustion products of the first and second chambers.

7. The dual stage inflator device of claim 1 additionally comprising:

a first igniter device operatively associated with the first chamber; and

a second igniter device operatively associated with the second chamber.

8. The dual stage inflator device of claim 7 wherein the housing comprises a cup-shaped base portion and a diffuser cap portion, the cup-shaped base portion including a first opening wherein the first igniter device is at least in part disposed, the cup-shaped base portion also including a second opening wherein the second igniter device is at least in part disposed, the first igniter device comprises an igniter housing and the divider plate additionally comprises a second opening wherein the igniter housing is disposed to place the first igniter device in operative association with the contents of the first chamber.

9. The dual stage inflator device of claim 7 wherein upon actuation of the second igniter device the second gas generant material ignites to produce the second combustion products including the second inflation gas and the plug element disposed in the first opening of the divider plate is displaced to permit gas flow communication from the second chamber into the first chamber through the first opening.

10. The dual stage inflator device of claim 7 wherein at least a portion of the second inflation gas exits from the inflator assembly through spaced apart gas exit ports formed in the housing at least in part defining the first chamber.

11. A dual stage inflator device comprising:

a housing comprises a cup-shaped base portion and a diffuser cap portion, the housing at least in part defining a first chamber containing a quantity of a first gas generant material ignitable to produce first combustion products including a first inflation gas, the housing also at least in part defining a second chamber containing a quantity of a second gas generant material ignitable to produce second combustion products including a second inflation gas, the housing at least in part defining the first chamber including a plurality of spaced apart gas exit ports to permit passage of first and second inflation gas from said inflator device;

a first igniter device operatively associated with the first chamber;

a second igniter device operatively associated with the second chamber;

a filter element disposed within the first chamber adjacent the plurality of spaced apart gas exit ports for filtration of combustion products of the first and second chambers;

a divider plate disposed and fixed within the housing, the divider plate at least in part separating the first chamber from the second chamber, the divider plate including a first opening to allow gas flow communication from the second chamber to the first chamber; and

a plug element disposed in the first opening of the divider plate to prevent gas flow communication between the first chamber and the second chamber through the first opening in a static state,

wherein upon actuation of the second igniter device, the second gas generant material ignites to produce the second combustion products including the second inflation gas and the plug element disposed in the first opening of the divider plate is displaced to permit gas flow communication from the second chamber into the first chamber through the first opening.

12. The dual stage inflator device of claim 11 wherein the plug element is press fit secured within the first opening when said inflator device is in a static state.

13. The dual stage inflator device of claim 11 wherein cup-shaped base portion including a first opening wherein the first igniter device is at least in part disposed, the cup-shaped base portion also including a second opening wherein the second igniter device is at least in part disposed, the first igniter device comprises an igniter housing and the divider plate additionally comprises a second opening wherein the igniter housing is disposed to place the first igniter device in operative association with the contents of the first chamber.

14. The dual stage inflator device of claim 11 wherein at least a portion of the second inflation gas exits from the inflator assembly through spaced apart gas exit ports formed in the housing at least in part defining the first chamber.

15. A method of operation for a dual stage inflator device that includes a housing at least in part defining a first chamber containing a quantity of a first gas generant material ignitable to produce first combustion products including a first inflation gas, the housing also at least in part defining a second chamber containing a quantity of a second gas generant material ignitable to produce second combustion products including a second inflation gas, the housing at least in part defining the first chamber including a plurality of spaced apart gas exit ports to permit passage of first and second inflation gas from the inflator device;

a first igniter device operatively associated with the first chamber;

a second igniter device operatively associated with the second chamber;

the inflator device also including a divider plate disposed and fixed within the housing, the divider plate separating the first chamber from the second chamber, the divider plate including a first opening to allow gas flow communication from the second chamber to the first chamber; and

a plug element disposed in the first opening of the divider plate to prevent gas flow communication between the first chamber and the second chamber through the first opening in a static state, the method comprising;

actuating the second igniter device to ignite the second gas generant material and to produce the second combustion products including the second inflation gas; and

displacing the plug element disposed in the first opening of the divider plate when the pressure against the plug element becomes sufficiently high to permit gas flow communication from the second chamber into the first chamber through the first opening.