Hybrid inflator device for a passive restraint air bag system

Patent metadata

Field	Value
Publication number	US-9205802-B1
Application number	US-201414459411-A
Country	US
Kind code	B1
Filing date	Aug 14, 2014
Priority date	Aug 14, 2014
Publication date	Dec 8, 2015
Grant date	Dec 8, 2015

Abstract

A hybrid inflator device for a passive restraint air bag system includes a housing defining a first chamber and a baffle passing through the first chamber. A supply of gas generant material is disposed in the first chamber and surrounds the baffle. An initiator is operative for creating a shock wave to open a burst disk and further operative to generate a hot gas to ignite the gas generant material. The initiator is disposed proximate a first end of the baffle. The baffle includes a reduced inner diameter portion and an unobstructed path extending along the length of the baffle.

First claim

What is claimed is:

1. A hybrid inflator device for a passive restraint air bag system, the hybrid inflator device comprising:
a housing defining a first chamber;
a baffle passing through the first chamber;
a supply of gas generant material disposed in the first chamber; and
an initiator for creating a shock wave to open a burst disk and generating a hot gas to ignite the gas generant material, the initiator disposed proximate a first end of the baffle;
wherein the baffle includes a first length from the first end to a reduced inner diameter portion and a second length from the reduced inner diameter portion to a second end of the baffle, the second length being greater than the first length, the baffle defining an unobstructed path extending along the first length and the second length.

2. The hybrid inflator device of claim 1 , wherein the gas generant material includes a plurality of gas generant tablets.

3. The hybrid inflator device of claim 2 , wherein the baffle positions and retains the plurality of gas generant tablets prior to ignition thereof.

4. The hybrid inflator device of claim 1 , wherein the baffle is perforated for facilitating ignition of the gas generant material with the hot gas.

5. The hybrid inflator device of claim 1 , wherein the reduced inner diameter portion of the baffle is greater than 50% of a nominal inner diameter of the baffle.

6. The hybrid inflator device of claim 1 , further comprising:
a ring for retaining the gas generant material;
a spring biasing the ring toward the gas generant material; and
a spring retainer for retaining the spring.

7. The hybrid inflator device of claim 6 , wherein the spring retainer engages an internal diameter of the housing.

8. The hybrid inflator device of claim 1 , further comprising a second chamber containing a pressurized gas.

9. The hybrid inflator device of claim 1 , wherein the hybrid inflator device is a hybrid inflator.

10. The hybrid inflator device of claim 1 , wherein the gas generant material surrounds the baffle.

11. A hybrid inflator device for a passive restraining air bag system, the hybrid inflator device comprising:
a housing;
a baffle disposed in the housing;
a gas generant material surrounding the baffle;
a ring retaining the gas generant material in an axial direction;
a spring biasing the ring toward the gas generant materials; and
a spring retainer for retaining the spring.

12. The hybrid inflator device of claim 11 , wherein the spring retainer engages an internal diameter of the housing.

13. The hybrid inflator device of claim 12 , wherein the spring retainer forms an interference fit with the housing.

14. The hybrid inflator device of claim 11 , wherein the spring retainer includes a main body portion and a plurality of tabs extending from the main body portion for engaging the internal diameter of the housing.

15. The hybrid inflator device of claim 14 , wherein the plurality of tabs extend from the main body portion at an angle.

16. The hybrid inflator device of claim 15 , wherein the plurality of tabs are adapted to inwardly flex upon the introduction of the spring retainer into the housing.

17. A hybrid inflator device for a passive restraint air bag system, the hybrid inflator device comprising:
a generally cylindrical housing having a first end and a second end, the housing defining a first chamber containing a gas generant material and a second chamber containing a pressurized gas;
a baffle passing through the first chamber such that the gas generant material surrounds the baffle, the baffle including a reduced inner diameter portion and a unobstructed path extending along the length of the baffle;
an initiator disposed in the housing proximate the first end, the initiator for creating a shock wave to open a burst disk and further operate to generate a hot gas to ignite the gas generant material;
a ring for retaining the gas generant material;
a spring biasing the ring toward the gas generant material; and
a spring retainer for retaining the spring.

18. The hybrid inflator device of claim 17 , wherein the reduced inner diameter portion of the baffle is greater than 50% of a nominal inner diameter of the baffle.

19. The hybrid inflator device of claim 17 , wherein the baffle includes a first length from the first end to the reduced inner diameter portion and a second length from the reduced inner diameter portion to a second end of the baffle, the second length being greater than the first length.

20. The hybrid inflator device of claim 17 , wherein the spring surrounds a portion of the baffle and a portion of the initiator.

21. A hybrid inflator device for a passive restraint air bag system, the hybrid inflator device comprising:
a housing defining a first chamber;
a baffle passing through the first chamber;
a supply of gas generant material disposed in the first chamber; and
an initiator for creating a shock wave to open a burst disk and generating a hot gas to ignite the gas generant material, the initiator disposed proximate a first end of the baffle;
wherein the first end of the baffle has a first inner diameter, the baffle further including a second end having a second inner diameter and a reduced inner diameter portion disposed between the first and second ends and including a reduced inner diameter smaller than both the first inner diameter and the second inner diameter.

22. The hybrid inflator device of claim 21 , wherein the reduced inner diameter portion of the baffle is greater than 50% of a nominal inner diameter of the baffle.

23. The hybrid inflator device of claim 22 , wherein the initiator includes a pressure dome spaced from the baffle.

24. The hybrid inflator device of claim 22 , wherein the baffle includes a reduced outer diameter portion proximate the reduced inner diameter portion.

Assignees

• Autoliv Asp Inc

Inventors

• Lang Gregory J
• Clark Kenneth J

Classifications

• B60R21/272 Primary

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

• B60R21/268

  using instantaneous release of stored pressurised gas {(B60R21/26005 takes precedence)} · CPC title