Gas generator including a multifunctional filter

• US 8,231,141 B2
• Filed: 06/19/2009
• Issued: 07/31/2012
• Est. Priority Date: 06/23/2008
• Status: Active Grant

• Current Assignee: TRW Airbag Systems GmbH (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Original Assignee: TRW Airbag Systems GmbH (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Inventors: Neumayer, Hans-Peter, Cristoforetti, Fabien
• Primary Examiner(s): BROWN, DREW J
• Application Number:
  US12/487,682
• Publication Number:
  US 20090315307A1
• Time in Patent Office: 1,138 Days
• Field of Search: 280/741, 280/736, 102/530, 102/531
• US Class Current: 280/741
• CPC Class Codes: B60R 2021/26011 using a filter through which the inflation gas passes
• CPC Class Codes: B60R 2021/2648 comprising a plurality of combustion chambers or sub-chambers
• CPC Class Codes: B60R 21/2644 using only solid reacting substances, e.g. pellets, powder
• CPC Class Codes: Y10T 29/49826 Assembling or joining

Abstract

The invention relates to a gas generator (10) for use in a safety device for motor vehicles comprising a housing and a propellant (4) contained in a combustion chamber (25) of the housing for generating a pressurized gas, the housing comprising a first housing part (40) and a second housing part (30) at least partly surrounded by the first housing part (40) and at least one igniter (6) for igniting the propellant (4), and an annular filter (50) surrounding the combustion chamber (25) in which the propellant (4) is located. The filter (50) comprises a peripheral portion (52) and a radial portion (51), the radial portion (51) serving as filling body for the propellant (4) in the combustion chamber (25).

Claims

1. A gas generator (10) for use in a safety device for motor vehicles comprising a housing and a propellant (4) contained in a combustion chamber (25) of the housing for generating a pressurized gas, said housing comprising a first housing part (40) and a second housing part (30) at least partly surrounded by said first housing part (40), an igniter (6) for igniting said propellant (4) and an annular filter (50) surrounding said combustion chamber (25) in which said propellant (4) is located, characterized in that said filter (50) has a peripheral portion (52) positioned in the combustion chamber (25) and a radial portion (51) that acts as a filling body for directing said propellant (4) into said combustion chamber (25).

2. The gas generator according to claim 1, characterized in that said peripheral portion (52) has a lower compressibility than said radial portion (51).

3. The gas generator according to claim 1, characterized in that said radial portion (51) is constructed to serve as a distance element for positioning an axially movable component of said gas generator.

4. The gas generator according to claim 1, characterized in that said radial portion (51) is constructed to radially position a movable component of said gas generator.

5. The gas generator according to claim 1, characterized in that said radial portion (51) is constructed to serve as a distance element for positioning an ignition mixing sleeve (5).

6. The gas generator according to claim 1, characterized in that said radial portion (51) is constructed to develop an elastic force action used for sealingly closing the housing.

7. The gas generator according to claim 1, characterized in that said radial portion (51) is constructed to serve as a spring element for holding said ignition mixing sleeve (5) in place.

8. A manufacturing process of a gas generator (10) for use in a safety device for motor vehicles, wherein said gas generator comprises a combustion chamber (25) for a propellant (4) and a filter (50) provided for retaining combustion products of said propellant, wherein said filter (50) includes a first portion (52) and a second portion (51) and the process comprises the steps of:

Placing said filter (50) into a lower housing part (30) of said gas generator such that, in the axial direction, said second portion (51) extends beyond said combustion chamber (25) of said gas generator (10), and filling propellant (4) into said combustion chamber (25) of said gas generator (10) using said second portion (51) of said filter (50) as a filling aid, characterized in that said step of filling is followed by a step of bending said second portion (51) of said filter (50) such that, at least in sections, it also extends radially above said propellant fill.

9. The manufacturing process according to claim 8, characterized in that said first portion (52) has a lower compressibility than said second portion (51).

10. The manufacturing process according to claim 8, characterized in that said step of bending said second portion (51) of said filter (50) is done by placing an upper housing part (40) onto said lower housing part (30).

11. The manufacturing process according to claim 10, characterized in that said upper housing part (40) is pushed so far onto said lower housing part (30) that said second portion (51) is compressed and serves as a filling body for said propellant (4).