Hybrid gas generator unit for inflating an airbag used in motor vehicle safety

• US 20030075909A1
• Filed: 09/20/2002
• Published: 04/24/2003
• Est. Priority Date: 10/19/2001
• Status: Active Grant

• Current Assignee: Livbag Snc
• Original Assignee: Livbag Snc
• Inventors: Perotto, Christian, Peremarty, Francois, Lebaudy, Franck
• Granted Patent: US 6,808,202 B2
• Time in Patent Office: Days
• US Class Current: 280/741
• CPC Class Codes: B60R 2021/0018 Roll-over
• CPC Class Codes: B60R 2021/26058 using a combination of inflators
• CPC Class Codes: B60R 2021/2617 Curtain bag nozzles
• CPC Class Codes: B60R 21/26 characterised by the inflation fluid source or means to control inflation fluid flow arrangement or mounting thereof to the vehicle B60R21/20; blasting cartridges for producing gas under pressure in general F42B3/04; initiators or igniters therefor F42B3/10
• CPC Class Codes: B60R 21/2646 the reacting substances being supported by the inflatable member walls, or by a flexible support within it
• CPC Class Codes: B60R 21/268 using instantaneous release of stored pressurised gas B60R21/26005 takes precedence

Abstract

The present invention relates to a hybrid gas generator unit (1) used to inflate at least one side airbag, characterized in that it comprises:

a pyrotechnic gas generator (2) produced using, on the one hand, a body (5) which contains an igniter (50) and which is provided with first and second ends (6, 7) and, on the other hand, a flexible element (8) which contains a pyrotechnic charge (10) and which is attached to the second end of the body;

a pressurized gas (4) reservoir (3) attached to the pyrotechnic gas generator at the first end of the body;

the said igniter being capable during operation, on the one hand, of initiating the combustion of the pyrotechnic charge contained in the flexible element and, on the other hand, of causing the pressurized gas contained in the reservoir to be released.

Claims

1. Hybrid gas generator unit (1) used for motor vehicle safety to inflate at least one side airbag, characterized in that it comprises:

a pyrotechnic gas generator (2) produced using, on the one hand, a body (5) which contains an electropyrotechnic igniter (50) and which is provided with first and second ends (6, 7) and, on the other hand, a flexible element (8) which contains a pyrotechnic charge (10) and which is attached to the second end of the body;

a pressurized gas (4) reservoir (3) attached to the pyrotechnic gas generator at the first end of the body;

the said igniter being capable during operation, on the one hand, of initiating the combustion of the pyrotechnic charge contained in the flexible element and, on the other hand, of causing the pressurized gas contained in the reservoir to be released.

2. Generator unit (1) according to claim 1, characterized in that the pyrotechnic charge (10) contained in the flexible element (8) is capable of generating a volume of gas sufficient to inflate the airbag in a time period of less than forty milliseconds.

3. Generator unit (1) according to either of claims 1 and 2, characterized in that, in operation, the pressurized gas (4) contained in the reservoir is released so as to keep the airbag inflated for a time period of about several seconds.

4. Generator unit (1) according to any one of the preceding claims, characterized in that the pyrotechnic charge contained in the flexible element is produced in the form of a cylindrical block (10) provided with a central channel (35).

5. Generator unit (1) according to any one of the preceding claims, characterized in that the pyrotechnic charge (10) contained in the flexible element (8) consists of a composite propellant comprising a charge based on ammonium perchlorate, sodium nitrate and an inert binder.

6. Generator unit (1) according to any one of the preceding claims, characterized in that a heat-shrunk pliant sleeve (12) grips and confines the pyrotechnic charge (10) contained in the flexible element (8).

7. Generator unit (1) according to claim 1, characterized in that the igniter (50) initiates the combustion of the pyrotechnic charge (10) contained in the flexible element (8) and causes the pressurized gas (4) contained in the reservoir to be released by means of booster charges (15, 33).

8. Generator unit (1) according to any one of the preceding claims, characterized in that the flexible element is produced using a pliant tube (8) made of a thermoplastic, provided with outlet orifices (52) uniformly distributed over its circumference and along its length.

9. Pyrotechnic gas generator (2) used in motor vehicle safety to inflate a side airbag, characterized in that it comprises:

a flexible element (8) containing a pyrotechnic charge produced in the form of a cylindrical block (10) provided with a central channel (35);

an electropyrotechnic igniter (50) located near the pyrotechnic charge.

10. Pyrotechnic generator (2) according to claim 9, characterized in that a heat-shrunk pliant sleeve (12) grips and confines the pyrotechnic charge (10).

11. Pyrotechnic generator (2) according to either of claims 9 and 10, characterized in that the flexible element is produced using a pliant tube (8) made of a thermoplastic, provided with outlet orifices (52) uniformly distributed over its circumference and along its length.