SAFETY VENTING WITH PASSIVELY CLOSEABLE VENTS

• US 20110031725A1
• Filed: 08/05/2009
• Published: 02/10/2011
• Est. Priority Date: 08/05/2009
• Status: Active Grant

• Current Assignee: Autoliv ASP Incorporated (Autoliv Incorporated)
• Original Assignee: Autoliv ASP Incorporated (Autoliv Incorporated)
• Inventors: Newkirk, John C., Rose, Larry D., Williams, Jeffrey D.
• Granted Patent: US 8,226,118 B2
• Time in Patent Office: Days
• US Class Current: 280/736
• CPC Class Codes: B60R 2021/23384 having ends which are movable or detachable during deployment
• CPC Class Codes: B60R 2021/2395 comprising means to control the venting
• CPC Class Codes: B60R 21/205 in dashboards
• CPC Class Codes: B60R 21/2338 Tethers
• CPC Class Codes: B60R 21/237 characterised by the way they are folded
• CPC Class Codes: B60R 21/239 characterised by their venting means

Abstract

The airbag cushion has a passive venting system that remains open or transitions to a closed position depending on the impact of the airbag with an occupant and the position of the occupant. The venting system self closes upon deployment when an occupant is not out of position but remains open when an occupant is out of position. The venting system self closes due to cushion membrane tension.

Claims

1. An airbag module, comprising:

an inflatable airbag cushion comprising a cushion membrane which defines an interior of the inflatable airbag cushion;

at least one closeable vent comprising a vent opening in the cushion membrane and a vent cover that extends over the vent opening;

wherein the vent cover has four sides,

wherein two of the sides are opposed to each other and are attached to the cushion membrane via stitches, and

wherein the other two sides include a side that is unattached to the cushion membrane and that is opposite a side that is attached to the cushion membrane via stitches;

wherein the vent cover is initially positioned to be distended away from the vent opening such that the vent is initially open;

wherein upon deployment of the inflatable airbag cushion with obstruction, the vent cover remains positioned such that the vent is open; and

wherein upon deployment of the inflatable airbag cushion without obstruction, the inflatable airbag cushion fully inflates such that the unattached side of the vent cover moves due to cushion membrane tension until the vent cover is taut and covers the vent opening to prevent inflation gas from exiting via the vent opening.

2. The airbag module of claim 1, wherein the vent opening is slit-shaped with a curvature that is concavely bowed downward away from the unattached side of the vent cover.

3. The airbag module of claim 1, wherein the unattached side of the vent cover has stitches extending along its length with a curvature that is concavely bowed downward toward the opposite side that is attached to the cushion membrane.

4. The airbag module of claim 3, wherein the stitches that extend along the length of the unattached side of the vent cover extend beyond the vent cover into the cushion membrane.

5. The airbag module of claim 3, wherein the attached side of the vent cover that is opposite the unattached side of the vent cover has stitches with a curvature that is convexly bowed upward toward the unattached side of the vent cover.

6. The airbag module of claim 1, wherein the stitches of the two opposing sides that are attached to the cushion membrane are generally straight and parallel with respect to each other.

7. The airbag module of claim 1, wherein the airbag cushion has a throat portion which receives inflation gas from an inflator, wherein the vent opening and vent cover are oriented downstream of the gas flow out of the throat portion at an angle that is about 900 with respect to the flow of gas out of the throat portion.

8. The airbag module of claim 1, wherein the airbag cushion has a throat portion which receives inflation gas from an inflator, wherein the vent opening and vent cover are oriented downstream of the gas flow out of the throat portion at an angle that is less than 90°

with respect to the flow of gas out of the throat portion.

9. An airbag module, comprising:

an inflatable airbag cushion comprising a cushion membrane which defines an interior of the inflatable airbag cushion, wherein the cushion has a front;

a closeable vent comprising a vent opening in the cushion membrane, a vent cover that extends over the vent opening, and a side panel that is adjacent to the opening;

a cord that extends through a hole in the vent cover, wherein the cord has an end that engages the side panel to pull the side panel to the vent cover, wherein the cord is coupled to the front of the airbag cushion,

wherein the cord is positioned to initially maintain the vent in an open position by distending the vent cover away from the vent opening, to continue maintaining the vent in the open position upon deployment of the inflatable airbag cushion with obstruction by continuing to distend the vent cover away from the vent opening, and to transition the vent to a closed position upon deployment of the inflatable airbag cushion without obstruction by drawing the cord taut due to full inflation of the inflatable airbag cushion, which draws the side panel to the vent cover and permits the vent cover to move due to cushion membrane tension and cover the vent opening to block the exit of inflation gas out of the vent opening.

10. The airbag module of claim 9, wherein the cord is sufficiently slack that it has a segment extending between the vent cover and the side panel with a length that is greater than the distance between the side panel and the vent cover when the vent cover is distended away from the vent opening.

11. The airbag module of claim 9, wherein the end of the cord that engages the side panel is sewn to the side panel, and wherein the cord is sewn to the front of the airbag cushion.

12. The airbag module of claim 9, wherein the vent opening is slit-shaped with a curvature that is concavely bowed downward toward an unattached side of the vent cover.

13. The airbag module of claim 9, wherein the vent cover and side panel are on opposite sides of the cushion membrane.

14. The airbag module of claim 9, wherein the cord is coupled to the front of the airbag cushion via a cord attachment that permits movement of the cord based on the tension of the cord.

15. The airbag module of claim 9, further comprising an additional closeable vent positioned at one of the opposing sides of the cushion opposite from the closeable vent, wherein the additional closeable vent comprises a vent opening in the cushion membrane, a vent cover that extends over the vent opening, and a side panel that is adjacent to the opening;

wherein the cord extends through a hole in the vent cover of the additional closeable vent and a hole in the side panel of the additional closeable vent, wherein the cord has a segment extending beyond the side panel of the additional closeable vent that terminates at a stop, whereby the cord is drawn taut upon deployment of the inflatable airbag cushion without obstruction and the stop pulls the side panel of the additional closeable vent to the vent cover of the additional closeable vent and the vent cover of the additional closeable vent moves due to cushion membrane tension such that inflation gas is blocked from exiting the vent opening of the additional closeable vent.

16. The airbag module of claim 15, wherein the cord is sufficiently slack that it has a segment extending between the vent cover of the vent and the side panel of the vent with a length that is greater than the distance between the side panel of the vent and the vent cover of the vent when the vent cover of the vent is distended away from the vent opening of the vent.

17. An airbag module, comprising:

an inflatable airbag cushion comprising a cushion membrane which defines an interior of the inflatable airbag cushion, wherein the cushion has a front;

a closeable vent comprising a vent opening in the cushion membrane and a vent cover that extends over the vent opening; and

a cord that engages the vent cover, wherein the cord extends through a hole in the cushion membrane at the front of the airbag cushion such that a segment of the cord that terminates at an end is positioned outside of the airbag cushion before deployment of the airbag cushion;

wherein the cord is positioned to initially maintain the vent in an open position by distending the vent cover away from the vent opening, to continue maintaining the vent in the open position upon deployment of the inflatable airbag cushion with obstruction by continuing to distend the vent cover away from the vent opening, and to transition the vent to a closed position upon deployment of the inflatable airbag cushion without obstruction due to full inflation of the inflatable airbag cushion, which pulls the cord through the hole such that the vent cover can move due to cushion membrane tension and cover the vent opening to block the exit of inflation gas out of the vent opening.

18. The airbag module of claim 17, wherein, before deployment, the airbag cushion comprises folds and rolls such that the airbag cushion has a compact configuration, wherein the segment of the cord extending out of the hole in the cushion membrane is in a rolled portion of the airbag cushion that has also been folded, which results in a frictional retention of the cord to initially maintain the vent in an open position, and to resist transitioning the vent to the closed position until deployment of the inflatable airbag cushion without obstruction.

19. The airbag module of claim 17, wherein the vent further comprises a side panel that is adjacent to the vent opening and is positioned to cooperate with the vent cover to block the exit of inflation gas out of the vent opening.

20. The airbag module of claim 19, wherein the side panel is not coupled to the cord.

21. The airbag module of claim 17, further comprising an additional closeable vent and an additional cord,

wherein the additional closeable vent is positioned at one of the opposing sides of the cushion opposite from the closeable vent, wherein the additional closeable vent comprises a vent opening in the cushion membrane and a vent cover that extends over the vent opening;

wherein the additional cord is attached to the vent cover of the additional closeable vent and extends out of an additional hole in the cushion membrane; and

wherein the additional cord is positioned to initially maintain the additional closeable vent in an open position by distending the vent cover of the additional closeable vent away from the vent opening, to continue maintaining the additional closeable vent in the open position upon deployment of the inflatable airbag cushion with obstruction by continuing to distend the vent cover of the additional closeable vent away from the vent opening of the additional closeable vent, and to transition the additional closeable vent to a closed position upon deployment of the inflatable airbag cushion without obstruction due to full inflation of the inflatable airbag cushion, which pulls the additional cord in the additional hole in the cushion membrane such that the vent cover of the additional closeable vent can move due to cushion membrane tension and cover the vent opening of the additional closeable vent to block the exit of inflation gas out of the vent opening of the additional closeable vent.

22. The airbag module of claim 17, further comprising an additional closeable vent positioned at one of the opposing sides of the cushion opposite from the closeable vent, wherein the additional closeable vent comprises a vent opening in the cushion membrane and a vent cover that extends over the vent opening;

wherein the cord extends from the vent cover of the closeable vent, through at least one hole in the vent cover of the additional closeable vent and out of the hole in the cushion membrane; and

wherein the cord is positioned to initially maintain the additional closeable vent in an open position by distending the vent cover of the additional closeable vent away from the vent opening, to continue maintaining the additional closeable vent in the open position upon deployment of the inflatable airbag cushion with obstruction by continuing to distend the vent cover of the additional closeable vent away from the vent opening of the additional closeable vent, and to transition the additional closeable vent to a closed position upon deployment of the inflatable airbag cushion without obstruction due to full inflation of the inflatable airbag cushion, which pulls the cord in the hole in the cushion membrane and in the hole of the vent cover of the additional closeable vent such that the vent cover of the additional closeable vent can move due to cushion membrane tension and cover the vent opening of the additional closeable vent to block the exit of inflation gas out of the vent opening of the additional closeable vent.

23. The airbag module of claim 17, wherein the segment of the cord that terminates at an end and is positioned outside of the airbag cushion before deployment of the airbag cushion, is pulled through the hole in the cushion membrane and into the inflatable airbag cushion upon deployment of the inflatable airbag cushion without obstruction.