Inflation device for automobile safety equipment

• US 6,447,008 B1
• Filed: 07/14/2000
• Issued: 09/10/2002
• Est. Priority Date: 07/16/1999
• Status: Expired due to Fees

• Current Assignee: Autoliv Development AB (Autoliv Incorporated)
• Original Assignee: Autoliv Development AB (Autoliv Incorporated)
• Inventors: Bohmann, Mats, Karlin, Mats
• Primary Examiner(s): Dickson, Paul N.
• Assistant Examiner(s): Dunn, David R.
• Application Number:
  US09/616,231
• Time in Patent Office: 788 Days
• Field of Search: 280/736, 280/737, 280/741, 102/530, 102/531
• US Class Current: 280/741
• CPC Class Codes: B60R 21/272 with means for increasing the pressure of the gas just before or during liberation, e.g. hybrid inflators
• 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

This invention relates to an inflation device for automobile safety equipment with a container in which a charge chamber for acceptance of a gas-producing charge and a discharge chamber with a discharge opening for connection with the safety device are provided, where a separating wall with an inside opening separates the two chambers axially from each other and is connected in a fluid-tight manner with a wall of said container by interlocking connecting means. According to the invention, such an inflation device excels through the fact that the connecting means are formed elastically in the axial direction in such manner that, when a predetermined pressure is reached in the charge chamber, they fail elastically and the separating wall is movable in the axial direction in the discharge chamber. The connecting means are released free of any radial expansion of the container wall.

Claims

1. Inflation device for automobile safety equipment having:

a container (1) in which a charge chamber (2) for acceptance of a gas-producing charge (3) and a discharge chamber (7) having a discharge opening (26) arranged to communicate with safety equipment, are arranged,

a separating wall (6) having an inside opening (19) structured and arranged to separate the two chambers (2,7) from each other in an axial direction of said container (1), and

interlocking connecting means (15,16,17) structured and arranged to connect said separating wall (6) fluid-tightly with a wall (4) of the container (1),

wherein the connecting means (15,16,17) are formed elastically and arranged such that said connecting means only fail in the axial direction when a predetermined pressure is reached in the charge chamber (2) and the separating wall (6) is structured and arranged to move in the axial direction within the discharge chamber (7).

2. Inflation device according to claim 1, wherein said connecting means are formed as a flange connection (15,16,17), having a flange (17) on said container wall (4) structured and arranged to point radially inwardly and a separating wall flange (15) pointing radially outwardly from said separating wall (6) and cooperating with said container flange (17),

said separating wall flange (15) structured and arranged elastically in the axial direction.

3. Inflation device according to claim 2, wherein said container flange (17) is integrally formed with said container wall (4), as a radially, pressed-in recess projecting radially inwardly from said container wall (4).

4. Inflation device according to claim 2, wherein the separating wall flange (15,16) is integrally formed with the separating wall (6) as a ring-like, circumferential ridge at an exterior circumference of the separating wall (6), forming a theoretical deformation point in the flange connection (15,16,17).

5. Inflation device according to claim 1, wherein said discharge opening (26) of said discharge chamber (7) has a larger cross-section than the inside opening (19) in the separating wall (6).

6. Inflation device according to claim 1, wherein the discharge opening (26) of the discharge chamber (7) is formed through said container wall (4) and points radially outwardly.

7. Inflation device according to claim 1, additionally comprising an exterior wall (5) on a side of said charge chamber (2) opposite said separating wall (6),

said exterior wall (5) being formed separately from said container wall (4) and coupled therewith by fluid-tight connecting means (12,13,14),

wherein said connecting means (12,13,14) for said exterior wall (5) is structured and arranged to be more resistant than said connecting means (15,16,17) for said separating wall (6) with said container (1).

8. Inflation device according to claim 7, wherein said connecting means (12,13,14) for said exterior wall (5) are formed as flange connections having a flange (13) on said exterior wall (5) pointing radially outwardly, and a flange (14) on said container wall (4) pointing radially inwardly and cooperating with the exterior wall flange (13).

9. Inflation device according to claim 8, wherein said container wall flange (14) is arranged on a side of said exterior wall flange (13) facing away from said charge chamber (2).

10. Inflation device according to claim 8, wherein said connecting means (12,13,14) for said exterior wall (5) is formed as an interlocking connection with the container wall (4) in both opposite axial directions.

11. Inflation device according to claim 1, wherein said container wall flange (17) is arranged on a side of said separating wall flange (15) facing away from said charge chamber (2).

12. Inflation device according to claim 11, wherein said container flange (17) comprises a rising inclined flank on a side facing one (15) of the separating wall flanges (15,16) and over which said respective separating wall flange (15) is pressed to be bent in an axial direction upon ignition whereby said respective separating wall flange (15) deforms or fails in the axial direction.

13. Inflation device according to claim 1, wherein said connecting means (15,16,17) for the separating wall (6) is formed as an interlocking connection with the container wall (4) closed in both opposite axial directions.

14. Inflation device according to claim 1, additionally comprising:

a pressure chamber (9) provided for compressed gas and structured and arranged to be connected with said discharge chamber (7),

a connecting opening (24) structured and arranged for communicating an interior of said pressure chamber (9) with said discharge chamber (7), and

a releasable seal (25) structured and arranged for fluid-tightly sealing said connecting opening (24),

said releasable seal (25) being formed and arranged to be released by gas pressure in said discharge chamber (2) after ignition of the gas-producing charge (3) therein.

15. Inflation device according to claim 14, additionally comprising a stopper (23) structured and arranged to plug the inside opening (19) in the separating wall (6),

said stopper (23) structured and arranged to release said opening (19) by being movable out from said inside opening (19) in a direction of said connecting opening (24) between said discharge chamber (7) and pressure chamber (9), such that seal (25) in said connecting opening (24) is opened by said movable stopper (23).

16. Inflation device according to claim 14, additionally comprising a separating wall (8) situated between said discharge chamber (7) and pressure chamber (9),

with said separating wall (6) situated between said charge chamber (2) and said discharge chamber (7) being supported thereon.

17. Inflation device according to claim 1, additionally comprising a symmetrical guide (20) extending in the axial direction and structured and arranged to support said separating wall (6) and being radially distanced from said container wall (4),

said guide (20) structured and arranged to be deformed or flattened in the axial direction.

18. Inflation device according to claim 17, wherein said guide (20) comprises a theoretical deformation zone formed as a radially inwardly pointed bead (22).

19. Inflation device according to claim 1, wherein said container (1) is formed essentially as a cylinder and said chambers (2,7) are concentrically arranged one after the other within said container (1) along a cylindrical axis thereof.

20. Inflation device according to claim 1, being built into automobile safety equipment, particularly an air bag arrangement.

21. Inflation device according to claim 1, wherein said connecting means (15,16,17) comprise two separate ring-shaped wall flanges (15,16) projecting radially outwardly and spaced at a distance from one another upon an exterior circumference of said separating wall (6),

a flange (17) extending from the wall (4) of the container (1) radially inwardly between the separate wall flanges (15,16) and projecting as a bead toward the inside, such that at least one gap is defined between said respective flanges (15,16,17) in unignited condition.

22. Inflation device according to claim 1, wherein said connecting means (15,16,17) comprises a pair of flanges (15,16) extending radially outwardly from an outer circumferential edge of said separating wall (6) and axially spaced from one another,

a flange (17) extending radially inwardly from the container wall (4) between said flange pair (15,16) and with a gap appearing between said flange pair (15,16) in unignited condition,

such that upon ignition, when pressure within said charge chamber (2) exceeds a predetermined value, one (15) of said flange pair (15,16) facing said charge chamber (2) deforms or fails in the axial direction and said separate wall (6) is pressed in the axial direction with the said flange (15) being bent in the axial direction and thrust over said container wall flange (17) which is provided with a rising inclined flank on a side facing said flange (15) and over which said flange (15) is pressed to be bent gently.

23. Inflation device for automobile safety equipment having:

a container (1) in which a charge chamber (2) for acceptance of a gas-producing charge (3) and a discharge chamber (7) having a discharge opening (26) arranged to communicate with safety equipment, are arranged,

a separating wall (6) having an inside opening (19) structured and arranged to separate the two chambers (2,7) from each other in an axial direction of said container (1),

interlocking connecting means (15,16,17) structured and arranged to connect said separating wall (6) fluid-tightly with a wall (4) of the container (1),

an exterior wall (5) on a side of said charge-chamber (2) opposite said separating wall (6),

said exterior wall (5) being formed separately from said container wall (4) and coupled therewith by fluid-tight connecting means (12,13,14), and

wherein said connecting means (12,13,14) for said exterior wall (5) is structured and arranged to be more resistant than said connecting means (15,16,17) for said separating wall (6) with said container (1) such that, upon ignition, said separating wall (6) always fails before said exterior wall (5).

24. The inflation device of claim 23, wherein the connecting means (15,16,17) for said separating wall (6) are formed elastically and arranged such that said connecting means (15,16,17) only fail in the axial direction when a predetermined pressure is reached in the charge chamber (2) and the separating wall (6) is structured and arranged to move in the axial direction within the discharge chamber (7).