Airbag apparatus

• US 20040135352A1
• Filed: 10/07/2003
• Published: 07/15/2004
• Est. Priority Date: 10/28/2002
• Status: Active Grant

• Current Assignee: Takata Corporation (Ningbo Junsheng Investment Group Co., Ltd.)
• Original Assignee: Takata Corporation (Ningbo Junsheng Investment Group Co., Ltd.)
• Inventors: Igawa, Tadahiro, Gu, Weixin
• Granted Patent: US 7,040,655 B2
• Time in Patent Office: Days
• US Class Current: 280/729
• CPC Class Codes: B60R 21/217 Inflation fluid source retainers, e.g. reaction canisters; Connection of bags, covers, diffusers or inflation fluid sources therewith or together
• CPC Class Codes: B60R 21/233 comprising a plurality of individual compartments; comprising two or more bag-like members, one within the other B60R21/232 takes precedence
• CPC Class Codes: B60R 21/2346 Soft diffusers
• CPC Class Codes: B60R 21/276 with means to vent the inflation fluid source, e.g. in case of overpressure B60R21/30 takes precedence; venting means on inflatable member walls B60R21/239

Abstract

An airbag apparatus including a vent hole that is reliably opened the pressure of an airbag has reached a predetermined level. An apparatus includes inner and outer bags placed in a retainer in folded conditions and the retainer is closed by a module cover. The retainer has a vent hole. The vent hole is closed by a lid or sheet type closing structure. The module cover is pushed open by the inflation pressure of the inner bag. The gas in the inner bag is discharged into the outer bag to inflate the outer bag. When the inner pressure of the outer bag has reached a predetermined level, the closing structure opens to open the vent hole.

Claims

1. An airbag apparatus comprising:

an airbag having an inner bag and an outer bag;

a gas generator configured to supply gas to the inner bag, wherein the inner bag includes an opening to allow gas to exit the inner bag to inflate the outer bag;

wherein the outer bag includes a vent hole;

wherein the vent hole includes a mechanism for maintaining the vent hole closed until the pressure of the gas in the outer bag reaches a predetermined level; and

wherein the vent hole is positioned so that gas escapes from the vent hole out of the outer bag and through a retainer for holding the gas generator.

2. The apparatus of claim 1, further comprising a cover connected to the retainer for covering the airbag in a folded condition, wherein the cover is pushed open by the inflation of the inner bag.

3. The apparatus of claim 1, wherein the mechanism includes a lid mounted to the retainer and the outerbag.

4. The apparatus of claim 3, wherein the lid includes a frangible portion that breaks when the pressure in the outer bag reaches a predetermined level to allow gas to escape out of the outer bag.

5. The apparatus of claim 3, wherein the closing mechanism includes a gasket between the lid and the retainer.

6. An airbag module for protecting the occupant of a vehicle, comprising an airbag including inner and outer bags and a retainer to which one of the bags is connected;

wherein the outer bag includes a vent hole positioned to allow an inflation gas to escape the outer bag through the retainer when the pressure in the outer bag reaches a predetermined level.

7. The module of claim 6, further comprising a mechanism for maintaining the vent hole closed until the pressure in the outer bag reaches a predetermined level.

8. The module of claim 7, wherein the mechanism includes a sheet covering a plurality of holes in the retainer.

9. The module of claim 8, wherein the sheet is configured to break when the pressure in the outer bag reaches a predetermined level.

10. The module of claim 6, wherein retainer is connected to a module cover that is configured to break when the pressure in the inner bag reaches a predetermined level.

11. The module of claim 8, wherein the sheet is connected to the retainer by an adhesive.