Air bag device for knee protection

• US 20030107206A1
• Filed: 12/30/2002
• Published: 06/12/2003
• Est. Priority Date: 07/07/2000
• Status: Active Grant

• Current Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Original Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Inventors: Takimoto, Masahiro, Kuriyama, Yuji, Koyama, Toru
• Granted Patent: US 7,182,365 B2
• Time in Patent Office: Days
• US Class Current: 280/730.1
• CPC Class Codes: B60R 2021/21506 comprising tearing tabs, legs or the like for holding the lid before deployment
• CPC Class Codes: B60R 2021/2163 with energy absorbing or elastic means
• CPC Class Codes: B60R 2021/23169 specially adapted for knee protection
• CPC Class Codes: B60R 2021/23316 Inner seams, e.g. creating separate compartments or used as tethering means
• CPC Class Codes: B60R 2021/23324 Inner walls crating separate compartments, e.g. communicating with vents
• CPC Class Codes: B60R 2021/23382 Internal tether means
• CPC Class Codes: B60R 2021/23386 External tether means
• CPC Class Codes: B60R 21/206 in the lower part of dashboards, e.g. for protecting the knees
• CPC Class Codes: B60R 21/215 characterised by the covers for the inflatable member B60R21/2176 takes precedence
• CPC Class Codes: B60R 21/216 comprising tether means for limitation of cover motion during deployment
• CPC Class Codes: B60R 21/2165 characterised by a tear line for defining a deployment opening
• CPC Class Codes: B60R 21/2171 specially adapted for elongated cylindrical or bottle-like inflators with a symmetry axis perpendicular to the main direction of bag deployment, e.g. extruded reaction canisters B60R21/2176 takes precedence
• CPC Class Codes: B60R 21/233 comprising a plurality of individual compartments; comprising two or more bag-like members, one within the other B60R21/232 takes precedence
• CPC Class Codes: B60R 21/2346 Soft diffusers
• CPC Class Codes: B60R 21/237 characterised by the way they are folded

Abstract

In a knee protecting airbag device (M1), an airbag (26) folded and housed below a steering column (3) is expanded and inflated while rising from the lower side of the steering column (3) along a column cover lower surface (9a) during an inflation process. The shape of the airbag having completed the inflation is in a generally plate shape capable of covering at least the lower surface of the column cover. Even if the knee of the driver comes close to the column cover when the driver depressing a brake pedal, therefore, the airbag being expanded and inflated goes smoothly into the clearance between the knee of the driver and the column cover lower surface. The airbag having completed the expansion and inflation protects the knee of the driver properly so that the knee may not interfere with the column cover.

Claims

1. A knee protecting airbag device for protecting knee of a driver with an airbag to be expanded and inflated by an inflating gas let in, wherein:

the airbag takes such a generally plate shape when having completed the expansion and inflation as covers at least the lower surface of a column cover covering a steering column; and

the airbag is so folded and housed below said steering column as to be expanded and inflated while rising along the lower surface of said column cover.

2. A knee protecting airbag device as set forth in claim 1, wherein said airbag is housed in a lower panel of an instrument panel below said column cover.

3. A knee protecting airbag device as set forth in claim 1, wherein said airbag is housed within the lower portion of said column cover.

4. A knee protecting airbag device as set forth in claim 1, wherein said airbag has a connection means to partially connect peripheral walls, as opposed to each other in the thickness direction, for keeping the generally plate shape when completing the inflation.

5. A knee protecting airbag device as set forth in claim 1, wherein:

in order that said airbag may have the completely inflated shape along the lower surface of said column cover, the upper side peripheral wall has a shorter longitudinal length than the longitudinal length of the lower side peripheral wall opposing to the upper side peripheral wall in the thickness direction.

6. A knee protecting airbag device as set forth in claim 1, wherein said airbag is formed by jointing a plurality of airbag elements which are cut solid to match the completely inflated shape.

7. A knee protecting airbag device as set forth in claim 1, wherein said airbag folded is housed in a case opened on the vehicular rear side.

8. A knee protecting airbag device as set forth in claim 7, wherein a guide plate portion is arranged on the peripheral edge of said case opening for guiding said airbag to be expanded and inflated along the column cover lower surface.

9. A knee protecting airbag device as set forth in claim 7, wherein said case is axially arranged generally in parallel with the axial direction of said steering column.

10. A knee protecting airbag device as set forth in claim 7, wherein:

said airbag folded and an inflator for feeding said inflating gas to said airbag are housed in said case to form an airbag assembly; and

said airbag assembly is mounted on a vehicle by being fixed on said steering column.

11. A knee protecting airbag device as set forth in claim 7, wherein:

said airbag folded and an inflator for feeding said inflating gas to said airbag are housed in said case to form an airbag assembly; and

said airbag assembly is mounted on a vehicle by being fixed on the vehicular body positioned on the left and right sides of said steering column.

12. A knee protecting airbag device as set forth in claim 7, wherein:

said airbag is housed while its vehicular rear side being covered with an airbag cover; and

said airbag cover includes a door portion to be opened by the push of the airbag being inflated, said door portion having a hinge portion on which to open at the lower end side thereof thereby opening downward.

13. A knee protecting airbag device as set forth in claim 12, wherein said airbag cover is made integral with the lower panel of the instrument panel below said column cover.

14. A knee protecting airbag device as set forth in claim 12, wherein said airbag cover is made integral with said column cover in the lower portion of said column cover.

15. A knee protecting airbag device as set forth in claim 12, wherein said door portion is constructed to open while breaking a breakable portion, as arranged on the peripheral edge thereof.

16. A knee protecting airbag device as set forth in claim 12, wherein said hinge portion is arranged on the vehicular front side of the upper end of said door portion.

17. A knee protecting airbag device as set forth in claim 12, wherein:

said door portion has an angle regulating means for regulating the opening angle connected thereto; and

said angle regulating means is so connected to said door portion as to retain the enough opening angle for said airbag to protrude from said case at the opening time, and to restrain the door from opening more than said opening angle.

18. A knee protecting airbag device as set forth in claim 12, wherein said door portion has a lower end side hinge portion arranged on the lower end side and has at least one auxiliary hinge portion arranged between said lower end side hinge portion and said door portion upper end, so that the portion on the upper side of the arrangement position of said auxiliary hinge portion may open downward.

19. A knee protecting airbag device as set forth in claim 7, wherein:

said case is covered on the vehicular rear side with an airbag cover;

said airbag cover includes a door portion to be opened by the push of said airbag being inflated;

said door portion has a hinge portion on which to open at either one of the upper end side or the lower end side, and has the lower end thereof arranged on the upper side of the lower end of the opening of said case so that the vertical width of said door portion may be smaller than the vertical width of the opening of said case; and

the lower side of the opening of said case is covered with the body portion of said airbag cover.

20. A knee protecting airbag device as set forth in claim 1, wherein said airbag includes a column cover side wall portion arranged on said column cover side when the airbag completes the expansion and inflation and a driver'"'"'s side wall portion arranged on the driver'"'"'s side when the airbag completes the expansion and inflation, and is folded by rolling at the upper end side on said column cover side wall portion.

21. A knee protecting airbag device as set forth in claim 20, wherein:

said airbag is folded through a longitudinal folding step, in which it is longitudinally folded from a flatly expanded state to bring both the left and right edges close to the center side, to a transverse width capable of being housed in the case; and

thereafter said airbag is folded by said rolling and is housed in said case.

22. A knee protecting airbag device as set forth in claim 21, wherein:

said airbag includes a central portion positioned near the center in the transverse direction, and end portions positioned on the left and right sides of said central portion; and

said longitudinal folding step consists of folding said left and right end portions individually on said column cover side wall portion.

23. A knee protecting airbag device as set forth in claim 1, wherein said airbag has a lower side as the upstream portion of said inflating gas and an upper side as the downstream portion of said inflating gas, so that said inflating gas flows to both the left and right sides in said upstream portion and then flows to the upper side of said airbag as said downstream portion.

24. A knee protecting airbag device as set forth in claim 23, wherein:

said airbag includes a column cover side wall portion on the side of said column cover and a driver'"'"'s side wall portion on the driver'"'"'s side;

within said airbag, there is transversely arranged a gas flow regulating member for connecting said column cover side wall portion and said driver'"'"'s side wall portion to form gas communication holes between the left and right ends thereof and the left and right sides of said airbag, thereby to partition said airbag into upstream portion and said downstream portion; and

said gas flow regulating member causes said inflating gas to flow to both the left and right sides in said upstream portion and then to flow through said gas communication holes to the upper side of said airbag as said downstream portion.

25. A knee protecting airbag device as set forth in claim 24, wherein said airbag includes a thickness regulating means for regulating the thickness of said airbag in said downstream portion.

26. A knee protecting airbag device as set forth in claim 24, wherein said gas flow regulating member is arranged in said airbag at such a position as becomes out of the airbag housing portion at the time of the expansion and inflation but near said housing portion.

27. A knee protecting airbag device as set forth in claim 24, wherein:

a thickness regulating means is arranged in said airbag for connecting said column cover side wall portion and said driver side wall portion; and

the connection portion to said driver side wall portion in said thickness regulating means is arranged on the upper stream side of said inflating gas than an interference portion of said airbag with the knee of the driver.