Multi-zone air bag curtain

• US 20060163849A1
• Filed: 05/27/2005
• Published: 07/27/2006
• Est. Priority Date: 01/21/2005
• Status: Active Grant

• Current Assignee: Milliken & Company
• Original Assignee: Milliken & Company
• Inventors: Keshavaraj, Ramesh
• Granted Patent: US 7,549,669 B2
• Time in Patent Office: Days
• US Class Current: 280/730.200
• CPC Class Codes: B60R 2021/23316 Inner seams, e.g. creating separate compartments or used as tethering means
• CPC Class Codes: B60R 2021/23386 External tether means
• CPC Class Codes: B60R 2021/23576 Sewing
• CPC Class Codes: B60R 2021/2358 Bonding
• CPC Class Codes: B60R 2021/23595 Sealing
• CPC Class Codes: B60R 2021/26058 using a combination of inflators
• CPC Class Codes: B60R 21/232 Curtain-type airbags deploying mainly in a vertical direction from their top edge
• CPC Class Codes: B60R 21/2338 Tethers
• CPC Class Codes: B60R 21/235 characterised by their material
• CPC Class Codes: B60R 21/239 characterised by their venting means

Abstract

An air bag curtain that incorporates at least a pair of substantially discrete inflation zones within the curtain structure such that upon failure or disengagement of one inflation zone, at least one other inflation zone remains operative.

Claims

1. An inflatable air bag curtain for occupant protection in a transportation vehicle, the air bag curtain comprising:

a first inflatable region comprising an elongate lower edge tensioning cell disposed adjacent a lower edge of the curtain and at least a second inflatable region disposed above the lower edge tensioning cell, wherein the first inflatable region is adapted to retain inflation gas in substantial isolation from the second inflatable region such that upon deployment of the curtain, retained inflation of the first inflatable region is independent of retained inflation in the second inflatable region.

2. The invention as recited in claim 1, wherein the first and second inflatable regions are operatively connected across a one way valve.

3. An inflatable air bag curtain for occupant protection in a transportation vehicle, the air bag curtain comprising:

a first mouth opening adapted to accept inflation gas generated by a first gas emitting inflator, the first mouth opening being in fluid communication with a gas transmission bolster portion of the curtain disposed adjacent an upper edge of the curtain; and

at least a second mouth opening adapted to accept inflation gas generated by a second gas emitting inflator, the second mouth opening being in fluid communication with a lower edge tensioning portion disposed adjacent a lower edge of the curtain, wherein the gas transmission bolster portion is in fluid isolation from the lower edge tensioning portion such that inflation within the gas transmission bolster portion is maintained independently from inflation within the lower edge tensioning portion.

4. The invention as recited in claim 3, wherein the gas transmission bolster portion has an elongate configuration extending at least partially along the length of the curtain.

5. The invention as recited in claim 3, further comprising at least a first group of gas accepting inflatable cells branching downwardly away from the gas transmission bolster portion such that a portion of the inflation gas accepted through the first mouth opening is transmitted into the first group of gas accepting inflatable cells.

6. The invention as recited in claim 5, wherein the lower edge tensioning portion comprises an elongate cell extending at least partially along the length of the curtain adjacent a lower edge.

7. The invention as recited in claim 6, wherein the gas transmission bolster portion, the first group of gas accepting inflatable cells and the lower edge tensioning portion are all disposed within a common web structure.

8. The invention as recited in claim 6, wherein the gas transmission bolster portion and the first group of gas accepting inflatable cells are disposed within a common web structure and wherein the lower edge tensioning portion is tethered in offset spaced relation to said web structure.

9. The invention as recited in claim 3, wherein the curtain includes one or more sewn seams comprising at least one stitching thread extending in perforating relation between a first panel and a second panel whereby discrete segments of the first panel and the second panel are held in opposing relation to one another, and wherein a layer of gas blocking sealant of discrete width is disposed between said discrete segments of the first panel and the second panel in surrounding relation to said at least one stitching thread, the gas blocking sealant having a tensile strength not greater than about 2.5 MPa and forming an adhesive bond to the first panel and the second panel with adhesive strength in excess of the internal cohesive strength of the sealant and wherein the sealant is characterized by gelation from liquid to a solid rubber phase at room temperature within about 180 minutes or less.

10. The invention as recited in claim 9, wherein the sealant is characterized by a gelation time from liquid to solid of not greater than about 180 minutes at room temperature.

11. The invention as recited in claim 9, wherein at least one of said first panel and said second panel further comprises a coating layer disposed in contacting relation to the gas blocking sealant.

12. The invention as recited in claim 11, wherein the coating layer comprises silicone.

13. The invention as recited in claim 9, wherein the layer of gas blocking sealant has a width of less than 10 millimeters and a thickness not greater than 1 millimeter.

14. An inflatable air bag curtain for occupant protection in a transportation vehicle, the air bag curtain comprising:

a first mouth opening adapted to accept inflation gas generated by a first gas emitting inflator, the first mouth opening being in fluid communication with an inflatable gas transmission bolster portion extending at least partially along the length of the curtain and at least a first group of gas accepting inflatable cells branching downwardly away from the gas transmission bolster portion such that inflation gas accepted through the first mouth opening is transmitted into the gas transmission bolster portion and into the first group of gas accepting inflatable cells; and

at least a second mouth opening adapted to accept inflation gas generated by a second gas emitting inflator, the second mouth opening being in fluid communication with an inflatable tensioning cell extending at least partially along the length of the curtain adjacent a lower edge of the curtain such that at least a portion of the first group of gas accepting inflatable cells is disposed between the tensioning cell and the gas transmission bolster portion, wherein the tensioning cell is in fluid isolation from the gas transmission bolster portion such that inflation within the tensioning cell is maintained independently from inflation within the gas transmission bolster portion.

15. The invention as recited in claim 14, further comprising a second group of gas accepting inflatable cells branching upwardly away from the tensioning channel such that a portion of the inflation gas accepted through the second mouth opening is transmitted into said second group of gas accepting inflatable cells.

16. The invention as recited in claim 15, wherein the first group of gas accepting inflatable cells and the second group of gas accepting inflatable cells define at least two inflatable cushioning zones within a web portion of the curtain and wherein a non-inflatable region is disposed between said inflatable cushioning zones.

17. An inflatable air bag curtain for occupant protection in a transportation vehicle, the air bag curtain comprising:

a lower edge tensioning zone comprising at least a first inflatable gas containment cell disposed adjacent a lower edge of the curtain and a head impact zone comprising at least a second inflatable gas containment cell disposed above the lower edge tensioning zone, wherein the first inflatable gas containment cell is at least partially enclosed by sewn seam boundaries comprising a layer of gas blocking sealant disposed between panel segments in surrounding relation to at least a portion of stitching threads forming the sewn seam boundaries and wherein the second inflatable gas containment cell is at least partially enclosed by gas permeable sewn seam boundaries substantially free of gas blocking sealant between panel segments and wherein the first inflatable gas containment cell is adapted to retain inflation gas in substantial isolation from the second inflatable gas containment cell such that upon deployment of the curtain, the lower edge tensioning zone retains inflation for a period in excess of the period of retained inflation of the head impact zone.

18. The invention as recited in claim 17, wherein the lower edge tensioning zone is characterized by a retained inflation period in excess of three minutes and wherein the head impact zone is characterized by a retained inflation period of less than three seconds.