Multi-chamber inflator

• US 6,095,561 A
• Filed: 03/05/1998
• Issued: 08/01/2000
• Est. Priority Date: 03/07/1997
• Status: Expired due to Fees

• Current Assignee: Automotive Systems Laboratory, Incorporated (Ningbo Junsheng Investment Group Co., Ltd.)
• Original Assignee: Automotive Systems Laboratory, Incorporated (Ningbo Junsheng Investment Group Co., Ltd.)
• Inventors: Siddiqui, Shahid A., Stratton, Rickey Lee
• Primary Examiner(s): Johnson, Brian L.
• Assistant Examiner(s): BRITTON, MICHAEL NMN
• Application Number:
  US09/036,885
• Time in Patent Office: 880 Days
• Field of Search: 280/741, 280/742
• US Class Current: 280/742
• CPC Class Codes: B60R 2021/2633 with a plurality of inflation levels
• 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

Abstract

A gas generator utilizes two segregated propellant container/combustion chambers, each having a plurality of nonazide propellant grains therein, and each having an igniter for separately igniting the propellant grains located within the respective chambers. A perforated insulating tube disposed between the two chambers precludes flame front and thermal propagation from one chamber to another, thus preventing redeployment of an activated airbag. Alternatively, a gas generator may contain two separate inflator subassemblies insulated to prevent heat conduction from one subassembly to another.

Claims

1. An air bag inflator comprising:

a first elongated and perforated cylindrical housing;

a second elongated and perforated cylindrical housing;

a first elongated and perforated cylindrical filter disposed radially inwardly of an inner wall of said first housing;

a second elongated and perforated cylindrical filter disposed radially inwardly of an inner wall of said second housing;

a first propellant chamber within said first filter;

a second propellant chamber within said second filter;

a perforated hollow tube connecting said first and second housings whereby heat transfer and flame propagation are eliminated therebetween and each chamber operates independently of the other;

a first propellant located within said first propellant chamber;

a second propellant located within said second propellant chamber;

a first means for igniting said first propellant; and

a second means for igniting said second propellant.

2. The inflator of claim 1 further comprising an inert heat insulator contained within said tube.

3. The inflator of claim 2 wherein said insulator comprises ceramic.

4. The inflator of claim 2 wherein said insulator comprises plastic.

5. The inflator of claim 2 wherein said insulator comprises carbon yarn.

6. An air bag inflator comprising:

a first inflator subassembly further comprising;

a first elongated and perforated cylindrical housing;

a first elongated and perforated cylindrical filter disposed radially inwardly of an inner wall of said first housing;

a first propellant chamber within said first filter;

a first propellant located within said first propellant chamber; and

a first means for igniting said first propellant;

a second inflator subassembly axially aligned with said first inflator subassembly further comprising;

a second elongated and perforated cylindrical housing;

a second elongated and perforated cylindrical filter disposed radially inwardly of an inner wall of said second housing;

a second propellant chamber within said second filter;

a second propellant located within said second propellant chamber;

a second means for igniting said second propellant; and

,

an inert heat insulator between said first and second subassemblies thereby preventing heat conduction between said first housing and said second housing.

7. The inflator of claim 6 wherein said insulator comprises air.

8. The inflator of claim 6 wherein said insulator comprises ceramic.

9. The inflator of claim 6 wherein said insulator comprises plastic.

10. The inflator of claim 6 wherein said insulator comprises carbon yarn.