Pyrotechnic Gas Generator Containing Means for Temporarily Storing Some of the Gases

• US 20090283006A1
• Filed: 08/29/2006
• Published: 11/19/2009
• Est. Priority Date: 09/01/2005
• Status: Active Grant

• Current Assignee: Autoliv AB (Autoliv Incorporated)
• Original Assignee: Autoliv AB (Autoliv Incorporated)
• Inventors: Abaziou, Xavier
• Granted Patent: US 8,011,302 B2
• Time in Patent Office: Days
• US Class Current: 102/530
• CPC Class Codes: B60R 21/2644 using only solid reacting substances, e.g. pellets, powder

Abstract

The present invention related to a pyrotechnic gas generator intended for motor vehicle safety, comprising a sealed housing (1), which contains:—at least one combustion chamber (C) containing a pyrotechnic charge (3), the combustion of which is initiated by an initiator (2) associated with the chamber;—at least one plenum chamber (T) for receiving the gases generated by the combustion of the charge (3) for removing them to the exterior, via at least one discharge aperture (10) formed in said housing (1). It is characterized in that said housing (1) also contains means (R) for temporarily storing at least some of the combustion gases.

Claims

1-13. -13. (canceled)

14. A pyrotechnic gas generator comprising:

a sealed housing having at least one combustion chamber and at least one plenum chamber;

the at least one combustion chamber containing a pyrotechnic charge,—

the combustion of which is initiated by an initiator associated with the chamber; and

the at least one plenum chamber for receiving the gases generated by the combustion of the charge for removing the gases from the housing via at least one discharge aperture formed in said housing, wherein the housing further includes means for temporarily storing at least some of the combustion gases.

15. The generator of claim 14, wherein the means for temporarily storing comprises a transit chamber separate from the combustion chamber in which at least some of the combustion gases are at least partly stored before their removal from the housing.

16. The generator of claim 15, wherein the exit of the gases from the transit chamber is based on the gas pressure prevailing in the transit chamber.

17. The generator of claim 15, which is tubular, wherein the generator includes a combustion chamber, a central plenum chamber and a transit chamber, longitudinally offset;

said chambers are separated in pairs, respectively by first and second partitions;

each partition has two communicating nozzles

the combustion chamber and transit chamber are connected directly to one another by a duct which terminates in two nozzles facing the first and second partitions respectively;

the nozzle of the second partition, which lacks a duct, has selective means for allowing the passage of gas, only from the transit chamber toward the plenum chamber.

18. The generator of claim 17, wherein the selective means comprises a check valve.

19. The generator of claim 17, wherein:

a side of the first partition turned toward the combustion chamber comprises a shutter of said nozzles which ruptures above a first value of the gas pressure in the combustion chamber, and

wherein a side of the second partition turned toward the transit chamber comprises a shutter of said nozzle lacking a duct, which ruptures above a second value of the gas pressure in the transit chamber.

20. The generator of claim 15, which is tubular, wherein the generator comprises two combustion chambers on either side of a plenum chamber and a transit chamber, both longitudinally offset;

said chambers being separated in pairs, respectively by a first, a second and a third partition, each partition has two communicating nozzles;

wherein the combustion chambers are directly connected to one another by a duct which terminates in two nozzles, respectively facing the first—

and third partitions, and passing through a nozzle of the second partition, the part of the duct passing through the transit chamber has apertures for communicating with this chamber, the nozzles of the third and the second partitions, which lack a duct, have selective means for allowing the flow of gas, only from the second combustion chamber toward the transit chamber, and from the transit chamber toward the plenum chamber.

23. The generator of claim 22, wherein

a side of the third partition turned toward the second combustion chamber, comprises a shutter of said nozzles which ruptures above a certain value of the gas pressure in said second combustion chamber;

and

wherein a side of the second partition turned toward the transit chamber comprises a shutter of said nozzle lacking a duct, which ruptures above a second value of the gas pressure in the transit chamber.

24. The generator of claim 23, which is tubular, wherein the generator comprises two combustion chambers on either side of a plenum chamber and a transit chamber, the transit chamber has the shape of a duct contained in the plenum chamber, said combustion chambers and plenum chamber are separated in pairs, respectively by first and second partitions, each partition-has a single communicating nozzle;

wherein the combustion chambers are directly-connected to one another by said duct which constitutes a transit chamber and which terminates in said nozzles; and

wherein the duct has a first and second series of apertures for communicating with the plenum chamber, placed respectively close to the first and second partitions, the second series being blocked by shutters which rupture above a predefined pressure.

25. The generator of claim 24, wherein the nozzle of the second partition is closed by a shutter which ruptures above a predefined pressure in said duct.

26. The generator of claim 23, wherein said transit chamber is annular and surrounds said combustion chamber;

said plenum chamber is also annular and surrounds said transit chamber;

the partitions separating the combustion chamber and the transit chamber on the one hand, and the transit chamber and the plenum chamber on the other, comprise communicating nozzles;

the communicating nozzles between the transit chamber and the plenum chamber are blocked by shutters, some opening above a certain pressure in the transit chamber, the others opening above a predefined and higher pressure in the transit chamber.

22. The generator of claim 21, wherein the selective means comprises a check valve.

23-1. The generator of claim 14, which comprises two distinct combustion chambers, wherein said means comprises a transit chamber, separate from the combustion chambers, in which at least some of the combustion gases from the first chamber are stored, these gases subsequently igniting the pyrotechnic charge of the second chamber.