INFLATABLE KNEE AIRBAGS AND INTERNAL TETHERS PRODUCED FROM SINGLE PANELS OF MATERIAL

• US 20100270779A1
• Filed: 04/27/2009
• Published: 10/28/2010
• Est. Priority Date: 04/27/2009
• Status: Active Grant

• Current Assignee: Autoliv ASP Incorporated (Autoliv Incorporated)
• Original Assignee: Autoliv ASP Incorporated (Autoliv Incorporated)
• Inventors: Enders, Mark L., Mueller, Louis, Lunt, Larry
• Granted Patent: US 8,118,325 B2
• Time in Patent Office: Days
• US Class Current: 280/730.100
• CPC Class Codes: B60R 2021/23169 specially adapted for knee protection
• CPC Class Codes: B60R 2021/23382 Internal tether means
• CPC Class Codes: B60R 21/2338 Tethers

Abstract

An airbag assembly with a reduced-cost knee airbag cushion and internal tethers can be formed from a single rectangular panel of material so that there is very little material waste. A pleat can be formed in a rear face so that the combination of tethers and pleat help the cushion deploy with favorable characteristics and adopt an arced shape when inflated. The cushion can have apertures for inserting an inflator with mounting stems partially within the cushion so that the mounting stems can be used to couple the cushion to an airbag housing. The assembly can also have a bag strap formed from a single piece of fabric that can wrap around a rolled and/or folded cushion. The assembly can also have a stabilizer strap that can be coupled to the cushion and to the airbag housing so that during deployment, the cushion does not skew or twist.

Claims

1. An inflatable airbag cushion formed from a single panel of material, wherein the airbag cushion has a middle portion formed by the removal of a first portion and a second portion from the single panel of material, the single panel of material being folded at the middle portion such that the airbag cushion has a front face and a rear face, wherein the middle portion has a width that is of a smaller magnitude than a width of the front face and the rear face, the front and rear face being coupled together along a perimeter such that the airbag cushion defines an inflatable void and has an upper portion and a lower portion, the airbag cushion further comprising:

a first tether formed from the first portion of material removed from the single panel of material, wherein the first tether is configured such that during inflatable airbag cushion deployment, the first tether partially limits a depth of the cushion when the cushion is inflated; and

,

a second tether formed from the second portion of material removed from the single panel of material, wherein the second tether is configured such that during inflatable airbag cushion deployment, the second tether partially limits a depth of the cushion when the cushion is inflated.

2. The airbag assembly of claim 1, wherein upon inflation during inflatable airbag cushion deployment, the cushion is configured such that it can adopt an arced shape.

3. The airbag assembly of claim 1, wherein the folded portion of the inflatable airbag cushion comprises an inflator attachment portion.

4. The airbag assembly of claim 3, wherein the inflator attachment portion is located on the front face of the airbag cushion.

5. The airbag assembly of claim 1, wherein the inflatable airbag cushion comprises seam reinforcements.

6. An inflatable airbag cushion formed from a rectangular shaped single panel of material that has a portion removed from each long-axis side of the rectangle to form a middle portion such that the single panel of material comprises an “

H”

shape, wherein the single panel of material is folded at the middle portion such that the airbag cushion has a front face and a rear face, wherein the middle portion has a width that is of a smaller magnitude than a width of the front face and the rear face, the front and rear face being coupled together along a perimeter such that the airbag cushion defines and inflatable void and has an upper portion and a lower portion, the airbag cushion further comprising;

a first tether formed from one of the portions of material removed from the rectangular single panel of material, the first tether being coupled to the first face of the inflatable airbag cushion, wherein the first tether extends to, and is coupled to, the second face such that the first tether is located within the inflatable void of the airbag cushion; and

,

a second tether formed from one of the portions of material removed from the rectangular single panel of material, the second tether being coupled to the first face of the inflatable airbag cushion, wherein the second tether extends to, and is coupled to, the second face such that the second tether is located within the inflatable void of the airbag cushion.

7. The inflatable airbag cushion of claim 6, wherein each of the first and second tethers are oriented such that they run transversely across a majority of the width of the inflatable airbag cushion and are approximately parallel with the fold of the folded middle portion.

8. The inflatable airbag cushion of claim 7, wherein the first tether is coupled to the front face between about 100 mm and about 200 mm from the fold of the folded middle portion.

9. The inflatable airbag cushion of claim 7, wherein the first tether comprises a plurality of apertures such that inflation gas may pass from an inflator-proximal side of the tether to an inflator-distal side of the tether.

10. The inflatable airbag cushion of claim 7, wherein the second tether is located between about 33% and about 50% of the distance between the first tether and an upper edge of the inflatable airbag cushion.

11. The inflatable airbag cushion of claim 7, wherein each of the points at which the first the first and second tethers are coupled to the rear face of the inflatable airbag cushion is located closer to an inflator than each of the points at which the first and second tethers are coupled to the front face of the inflatable airbag cushion.

12. The inflatable airbag cushion of claim 11, wherein the distance by which each of the rear face tether attachment points are closer to the inflator than each of the front face tether attachment points is between about 20 mm to about 30 mm.

13. The inflatable airbag cushion of claim 7, wherein the rear face of the inflatable airbag cushion comprises a pleat that runs transversely across the inflatable airbag cushion.

14. The inflatable airbag cushion of claim 13, wherein the pleat comprises a fold of the rear face of the airbag cushion that is sewn such that the folded portion projects in to the inflatable void.

15. The inflatable airbag cushion of claim 14, wherein the pleat reduces a length of the rear face by about 40 mm to about 100 mm, compared to a length of the front cushion.

16. The inflatable airbag cushion of claim 15, wherein the first tether, the second tether, and the pleat are configured such that when the airbag cushion is fully inflated and viewed from a side view, it adopts a concave arced shape, wherein the apex of the arc projects away from a cabin of a vehicle and the ends of the arc project toward the cabin of the vehicle.

17. The inflatable airbag cushion of claim 6, wherein the cushion further comprises at least one heat panel that is coupled to the cushion at an inflator attachment portion of the cushion.

18. The inflatable airbag cushion of claim 17, wherein the at least one heat panel comprises a material selected from the group consisting of fiber glass, carbon fibers, hemp, nylon, polyester, para-aramid synthetic fibers, or a combination of the preceding materials.

19. The heat panel of claim 18, wherein the heat panel is coated with a flexible epoxy selected from the group consisting of neoprene, urethane, phenolic materials, or a combination of the preceding substances.

20. The inflatable airbag cushion of claim 17, wherein the heat panel comprises fiber glass fibers selected from the group consisting of E-glass, S-glass, S2-glass, or a combination of the preceding fibers.