Cold Gas Generator for an Airbag System

• US 20030137136A1
• Filed: 12/27/2002
• Published: 07/24/2003
• Est. Priority Date: 06/29/2000
• Status: Active Grant

• Current Assignee: Welz Industrieprodukte GmbH (Huapeng Trading GmbH)
• Original Assignee: Welz Industrieprodukte GmbH (Huapeng Trading GmbH)
• Inventors: Welz, Siegfried
• Granted Patent: US 6,814,371 B2
• Time in Patent Office: Days
• US Class Current: 280/741
• CPC Class Codes: B60R 2021/23107 the bag being integrated in a multi-bag system
• CPC Class Codes: B60R 2021/2685 comprising a plurality of pressure chambers
• CPC Class Codes: B60R 21/268 using instantaneous release of stored pressurised gas B60R21/26005 takes precedence

Abstract

Abstract of Disclosure

A cold gas generator for an airbag system has a storage device having an interior filled with a gas under pressure. The interior is divided into at least two partial chambers. Gas outlet openings closed in a rest state of the cold gas generator are provided, wherein one of the gas outlet openings is correlated with one of the at least two partial chambers, respectively. An opening mechanism is provided for actuating, when needed, all of the gas outlet openings together and for filling several airbags with the gas.

Claims

1. WHAT IS CLAIMED IS:

1.A cold gas generator for an airbag system, the cold gas generator comprising;

a storage device (1) having an interior (2) filled with a gas (3) under pressure;

wherein the interior (2) is divided into at least two partial chambers (8,

     9);

gas outlet openings (4,

     5) closed in a rest state of the cold gas generator, wherein one of the gas outlet openings (4,

     5) is correlated with one of the at least two partial chambers (8,

     9), respectively;

an opening mechanism (6) for actuating, when needed, all of the gas outlet openings (4,

     5) together and for filling several airbags (7) with the gas (3).

2. The cold gas generator according to claim 1, wherein the storage device (1) comprises an approximately cylindrical center part (11) with a cylindrical peripheral wall (12) extending in a longitudinal direction (10) of the storage device (1), wherein the storage device (1) comprises a piston (13) provided in the interior (2) in the area of the center part (11), wherein the piston (13) is moved from a rest position (14) in a direction of the longitudinal axis (10) into an outflow position (15), when the opening mechanism (6) is actuated, and wherein one of the gas outlet openings (5) is closed in the rest position (14) of the piston (13) and is open in the outflow position (15) of the piston (13).

3. The cold gas generator according to claim 1, wherein the storage device (1) comprises an approximately cylindrical center part (11) with a cylindrical peripheral wall (12) extending in a longitudinal direction (10) of the storage device (1), wherein the storage device (1) comprises several pistons (13) provided in the interior (2), wherein each one of the pistons (13) separates two adjacent ones of the partial chambers (8, 9) from one another, respectively, wherein the pistons (13) are moved from a rest position (14) in a direction of the longitudinal axis (10) into an outflow position (15) when the opening mechanism (6) is actuated, and wherein the gas outlet openings (5) of the partial chambers are closed in the rest position (14) of the pistons (13) and are open in the outflow position (15) and fill one airbag, respectively.

4. The cold gas generator according to claim 3, wherein the storage device (1) further comprises at least one piston rod (16) connecting the pistons (13) to one another.

5. The cold gas generator according to claim 4, wherein the piston rod (16) is tubular.

6. The cold gas generator according to claim 3, wherein the pistons (13) in the rest position (14) are kept in equilibrium by the gas pressure within the storage device (1) and wherein the opening mechanism (6) is configured to act on one of the gas outlet openings (4) arranged at an end (21) of the storage device (1).

7. The cold gas generator according to claim 6, wherein the opening mechanism (6) comprises:

a sealing disk provided with a rated break-off location (17) and configured to close the gas outlet opening (4) arranged at the end of the storage device (1);

a support element (19) supporting the sealing disk (18); and

a pyrotechnical actuator (20) acting on the support element (19).

8. The cold gas generator according to claim 6, wherein the peripheral wall (12) has a tapering cross-section in the area of the end (21) of the storage device (1).

9. The cold gas generator according to claim 6, wherein the pistons (13) comprise a connecting channel (22), respectively, for pressure transmission between two of the partial chambers (8,9) separated by one of the piston (13), respectively, wherein the connecting channel (22) comprises a flow throttle (23).

10. The cold gas generator according to claim 9, wherein the pistons (13) have a blind bore (24), respectively, for receiving the at least one piston rod (16) and wherein the connecting channel (22) is arranged approximately coaxially in a bottom (25) of the blind bore (24) .

11. The cold gas generator according to claim 3, wherein the pistons (13) are sealed by an O-ring (26) relative to the peripheral wall (12), respectively.

12. The cold gas generator according to claim 3, wherein the gas outlet openings (5) are arranged in the peripheral wall (12) and are covered by the pistons (13) in the rest position (14).

13. The cold gas generator according to claim 12, wherein the gas outlet openings (5), in the rest position (14) of the pistons (13), are closed by a sealing sleeve (27), respectively, wherein the sealing sleeve (27) is comprised of a base body (28) fastened on the peripheral wall (12) and of a closure body (30) connected by a rated break-off location (29) to the base body (28) and attached to the pistons (13).

14. The cold gas generator according to claim 13, wherein the base body (28) is an approximately circular disk (31) having a thickness (d₁), wherein the closure body (30) is a cylindrical pin having a diameter (D₁) and formed as a monolithic part coaxially on the circular disk (31), wherein the pin engages a bore (33) provided in the piston (13), and wherein the circular disk (31) has a substantially coaxial outflow bore (34) whose diameter (D₂) is somewhat smaller than the diameter (D₁) of the pin (32) and whose depth (d₂) corresponds approximately at least to the thickness (d₁) of the circular disk (31).

15. The cold gas generator according to claim 14, wherein the pistons (13) on a side facing away from the outflow position (15) have an overlap length (L) relative to the outflow bore (34), respectively.

16. The cold gas generator according to claim 2, wherein the piston (13) in the rest position (14) is kept in equilibrium by the gas pressure within the storage device (1) and wherein the opening mechanism (6) is configured to act on one of the gas outlet openings (4) arranged at an end (21) of the storage device (1).

17. The cold gas generator according to claim 16, wherein the opening mechanism (6) comprises:

a sealing disk provided with a rated break-off location (17) and configured to close the gas outlet opening (4) arranged at the end of the storage device (1);

a support element (19) supporting the sealing disk (18); and

a pyrotechnical actuator (20) acting on the support element (19).

18. The cold gas generator according to claim 16, wherein the peripheral wall (12) has a tapering cross-section in the area of the end (21) of the storage device (1).

19. The cold gas generator according to claim 16, wherein the piston (13) comprises a connecting channel (22), respectively, for pressure transmission between the two partial chambers (8, 9) separated by the piston (13), wherein the connecting channel (22) comprises a flow throttle (23).

20. The cold gas generator according to claim 2, wherein the piston (13) is sealed by an O-ring (26) relative to the peripheral wall (12).

21. The cold gas generator according to claim 2, wherein the gas outlet opening (5) is arranged in the peripheral wall (12) and covered by the piston (13) in the rest position (14).

22. The cold gas generator according to claim 21, wherein the gas outlet opening (5), in the rest position (14) of the piston (13), is closed by a sealing sleeve (27), wherein the sealing sleeve (27) is comprised of a base body (28) fastened on the peripheral wall (12) and of a closure body (30) connected by a rated break-off location (29) to the base body (28) and attached to the piston (13).

23. The cold gas generator according to claim 22, wherein the base body (28) is an approximately circular disk (31) having a thickness (d₁), wherein the closure body (30) is a cylindrical pin having a diameter (D₁) and formed as a monolithic part coaxially on the circular disk (31), wherein the pin engages a bore (33) provided in the piston (13), and wherein the circular disk (31) has a substantially coaxial outflow bore (34) whose diameter (D₂) is somewhat smaller than the diameter (D₁) of the pin (32) and whose depth (d₂) corresponds approximately at least to the thickness (d₁) of the circular disk (31).

24. The cold gas generator according to claim 23, wherein the piston (13) on a side facing away from the outflow position (15) has an overlap length (L) relative to the outflow bore (34).

25. The cold gas generator according to claim 1, wherein the gas (3) contained in the interior (2) is primarily helium.