Gas generator for a vehicle occupant restraint system and airbag module having such a gas generator

• US 20070085310A1
• Filed: 10/10/2006
• Published: 04/19/2007
• Est. Priority Date: 10/17/2005
• Status: Abandoned Application

• Current Assignee: TRW Automotive GmbH (Apollo Global Management, Inc.)
• Original Assignee: TRW Automotive GmbH (Apollo Global Management, Inc.)
• Inventors: Lutz, Joachim, Debler, Jens
• Application Number:
  US11/545,317
• Publication Number:
  US 20070085310A1
• Time in Patent Office: Days
• US Class Current: 280/736
• 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

A gas generator (8) for a vehicle occupant restraint system includes a gas generator housing (25), the gas generator housing (25) defining a distribution chamber (14) and a generator chamber (12) from which gas flows into the distribution chamber (14) after the gas generator (8) has been activated, the distribution chamber (14) having at least one first outflow opening (26) that conveys the gas into an airbag (24), the distribution chamber (14) further having a pyrotechnical device (18) that, when it is triggered, releases at least one second outflow opening (28) in order to discharge gas to the environment.

The invention also relates to an airbag module having such a gas generator (8).

Claims

1. A gas generator (8) for a vehicle occupant restraint system, comprising a gas generator housing (25), said gas generator housing (25) defining a distribution chamber (14) and a generator chamber (12) from which gas flows into said distribution chamber (14) after said gas generator (8) has been activated, said distribution chamber (14) having at least one first outflow opening (26) that conveys said gas into an airbag (24), said distribution chamber (14) further having a pyrotechnical device (18) that, when it is triggered, releases at least one second outflow opening (28) in order to discharge gas to an environment.

2. The gas generator (8) according to claim 1, wherein said pyrotechnical device (18) is an explosive bolt that is arranged in an outer wall of said distribution chamber (14).

3. The gas generator (8) according to claim 1, wherein several second outflow openings (28) are provided and arranged in such a way that they discharge outflowing gas to said environment in a shear-neutral manner.

4. The gas generator (8) according to claim 1, wherein said second outflow opening (28) is integrated into said pyrotechnical device (18).

5. The gas generator (8) according to claim 1, wherein a membrane (30) is present that divides said distribution chamber (14) into two areas, a first area containing said first outflow opening (26) and a second area containing said second outflow opening (28) and, after said pyrotechnical device (18) has been activated, it destroys said membrane (30).

6. The gas generator (8) according to claim 5, wherein said pyrotechnical device (18) is arranged in said second area of said distribution chamber (14).

7. The gas generator (8) according to claim 1, wherein said gas generator (8) is a tubular gas generator with a tube axis (A), said generator chamber (12) and said distribution chamber (14) being arranged axially behind one another.

8. The gas generator (8) according to claim 1, wherein said distribution chamber (14) is formed by a separate part attached to said generator chamber (12).

9. The gas generator (8) according to claim 1, wherein said gas generator (8) is a cold gas generator, said generator chamber (12) having a chamber filled with compressed gas.

10. The gas generator (8) according to claim 1, wherein said gas generator (8) is a hot gas generator, said generator chamber (12) having a combustion chamber.

11. An airbag module having a gas generator (8) according to claim 1, wherein said gas generator (8) is accommodated and attached in a module housing (10), said distribution chamber (14) being configured in such a way that a section of said distribution chamber (14) having said second outflow opening (28) extends through an opening in said module housing (10) in order to discharge gas from said airbag module to said environment.

12. The airbag module according to claim 11, wherein at least one attachment bolt (20) is provided between said distribution chamber (14) and said module housing (10) in order to attach said gas generator (8) to said module housing (10), said pyrotechnical device (18) for releasing said second outflow opening (28) being integrated into said attachment bolt (20).

13. The airbag module according to claim 11, wherein a shape of said distribution chamber (14) and cross sections of said first and second outflow openings (26, 28) are coordinated with each other in such a way that, when said pyrotechnical device (18) is triggered, a gas mass flow into said airbag (24) is established that amounts to between 20% and 80%, preferably about 50%, of a value achieved when said second outflow opening (28) is closed.