Hybrid inflator, method of operating a hybrid inflator, airbag module and vehicle safety system

Patent metadata

Field	Value
Publication number	US-10336289-B2
Application number	US-201715423674-A
Country	US
Kind code	B2
Filing date	Feb 3, 2017
Priority date	Feb 12, 2016
Publication date	Jul 2, 2019
Grant date	Jul 2, 2019

Abstract

The invention relates to a hybrid inflator (10) comprising a combustion chamber (20) and a pressure gas tank (30), wherein in the idle state of the hybrid inflator (10) an outlet opening (31) of the pressure gas tank (30) is closed by a bursting element (32) which in the case of function of the hybrid inflator (10) can be destroyed by means of a penetration element (40), wherein a mixing chamber (70) is formed between the pressure gas tank (30) and the combustion chamber (20). In accordance with the invention, between the combustion chamber (20) and the mixing chamber (70) at least in portions a partition wall (80) having a combustion chamber side (81) and a mixing chamber side (82) is formed, wherein the partition wall (80) includes at least one combustion chamber opening (85) which in the idle state of the hybrid inflator (10) is closed by a cover (88) formed on the mixing chamber side (82) of the partition wall (80).

First claim

The invention claimed is:

1. A hybrid inflator ( 10 ) comprising
a combustion chamber ( 20 ) and a pressure gas tank ( 30 ), wherein in an idle state of the hybrid inflator ( 10 ) an outlet opening ( 31 ) of the pressure gas tank ( 30 ) is closed by a bursting element ( 32 ) which in the case of function of the hybrid inflator ( 10 ) can be destroyed by means of a penetration element ( 40 ) displaced by ignition gas, with a mixing chamber ( 70 ) being formed between the pressure gas tank ( 30 ) and the combustion chamber ( 20 ), the penetration element ( 40 ) including a first hollow portion ( 43 ) for receiving the ignition gas for displacing the penetration element ( 40 ) into the bursting element ( 32 ) and a second hollow portion ( 95 ) for fluidly connecting the pressure gas tank ( 30 ) and the mixing chamber ( 70 ) when the bursting element ( 32 ) is destroyed, wherein between the combustion chamber ( 20 ) and the mixing chamber ( 70 ) at least in portions a partition wall ( 80 ) having a combustion chamber side ( 81 ) and a mixing chamber side ( 82 ) is formed, wherein the partition wall ( 80 ) includes at least one combustion chamber opening ( 85 ) which in the idle state of the hybrid inflator ( 10 ) is closed by a cover ( 88 ) formed on the mixing chamber side ( 82 ) of the partition wall ( 80 ).

2. The hybrid inflator ( 10 ) according to claim 1 , wherein the cover ( 88 ) is a membrane and/or film made from metal, wherein the mixing chamber ( 70 ) has at least one generator opening ( 75 ) for fluid-communicating the hybrid inflator ( 10 ) with an element to be inflated.

3. The hybrid inflator ( 10 ) according to claim 1 , wherein in the case of function of the hybrid inflator ( 10 ) the gas pressure generated or adapted to be generated within the combustion chamber ( 20 ) is lower than the pressure prevailing in the pressure gas tank ( 30 ) in the idle state of the hybrid inflator ( 10 ).

4. The hybrid inflator ( 10 ) according to claim 3 , wherein in the combustion chamber ( 20 ) an ignition tube ( 60 ) is formed, wherein the penetration element ( 40 ) is longitudinally movable at least in portions inside the ignition tube ( 60 ), wherein the ignition tube ( 60 ) is filled with a pyrotechnical igniting mixture and/or a pyrotechnical booster charge, the ignition tube ( 60 ) including at least one opening ( 64 ) for fluid communicating an inner area of the ignition tube ( 60 ) with the combustion chamber ( 20 ).

5. The hybrid inflator ( 10 ) according to claim 4 , wherein the ignition tube ( 60 ) at its end ( 63 ) facing the pressure gas tank ( 30 ) includes a collar portion ( 65 ) forming the partition wall ( 80 ) between the combustion chamber ( 20 ) and the mixing chamber ( 70 ), wherein in the longitudinal extension (L) of the hybrid inflator ( 10 ) the ignition tube ( 60 ) is completely surrounded by a combustion chamber ( 20 ) of circular ring shape in cross-section.

6. An airbag module comprising a hybrid inflator ( 10 ) according to claim 1 .

7. The hybrid inflator according to claim 1 , wherein the cover is a tamping.

8. The hybrid inflator according to claim 1 , wherein the cover is formed from one of steel, copper, and aluminum.

9. The hybrid inflator according to claim 1 , wherein the mixing chamber fluidly communicates the hybrid inflator with an airbag.

10. The hybrid inflator according to claim 1 , wherein the second hollow portion includes at least one axially extending recess and at least one radially extending gas outlet.

11. The hybrid inflator according to claim 1 , wherein the at least one radially extending gas outlet is formed as an extension of the at least one recess.

12. The hybrid inflator according to claim 1 , wherein the second hollow portion extends between penetration legs on the penetration element that destroy the bursting element.

13. The hybrid inflator according to claim 1 wherein further comprising an annular groove encircling the first hollow portion for receiving a sealing ring.

14. The hybrid inflator according to claim 1 , wherein at least a portion of the penetration element is spaced axially from the pressure gas tank when the hybrid inflator is in the idle state.

15. A hybrid inflator comprising:
a combustion chamber;
a pressure gas tank having an outlet opening;
a bursting element closing the outlet opening when the hybrid inflator is in an idle state;
a mixing chamber formed between the pressure gas tank and the combustion chamber;
a partition wall formed at least in portions between the combustion chamber and the mixing chamber and having a combustion chamber side and a mixing chamber side, the partition wall includes at least one combustion chamber opening;
a cover formed on the mixing chamber side of the partition wall for closing the at least one combustion chamber opening when the hybrid inflator is in the idle state; and
a penetration element movable by ignition gas for destroying the bursting element when the hybrid inflator is in a functional case, the penetration element including a first hollow portion for receiving the ignition gas for displacing the penetration element into the bursting element and a second hollow portion for fluidly connecting the pressure gas tank and the mixing chamber when the bursting element is destroyed.

Assignees

• Trw Airbag Sys Gmbh

Inventors

• Ebner Johannes
• Bierwirth Sebastian
• Oberstarr Martin
• Last Detlef

Classifications

• B25H3/02

  Boxes · CPC title

• B60R21/26 Primary

  characterised by the inflation fluid source or means to control inflation fluid flow {(arrangement or mounting thereof to the vehicle B60R21/20; blasting cartridges for producing gas under pressure in general F42B3/04; initiators or igniters therefor F42B3/10)} · CPC title

• B60R21/272 Primary

  with means for increasing the pressure of the gas just before or during liberation, e.g. hybrid inflators · CPC title

• B60R21/274

  characterised by means to rupture or open the fluid source · CPC title

• B60R2021/26047

  of film shape · CPC title