Knee protecting airbag device

• US 20020171230A1
• Filed: 05/03/2002
• Published: 11/21/2002
• Est. Priority Date: 05/21/2001
• Status: Active Grant

• Current Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Original Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Inventors: Funabashi, Satoshi, Takimoto, Masahiro, Koyama, Toru
• Granted Patent: US 6,752,417 B2
• Time in Patent Office: Days
• US Class Current: 280/730.1
• CPC Class Codes: B60R 2021/0051 Knees
• CPC Class Codes: B60R 2021/21512 the lid being displaced towards the occupant during deployment B60R2021/2161, B60R2021/21525 take precedence
• CPC Class Codes: B60R 2021/23169 specially adapted for knee protection
• CPC Class Codes: B60R 21/206 in the lower part of dashboards, e.g. for protecting the knees
• 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 21/237 characterised by the way they are folded

Abstract

A knee protecting airbag device is comprising a folded airbag housed on the lower side of a member attached to the vehicle body and in front of the knees of a seated passenger and deploying in front of the knees of the passenger. The airbag extends and expands when fed with an inflating gas, protruding toward the rear of the vehicle from a housing case thereby to protect the knees of the passenger. The airbag includes a lower expansion portion on the upstream side of the gas and an upper expansion portion on the downstream side. The lower expansion portion protrudes from the opening of the case toward the rear of the vehicle to cover the front sides of the knees. The upper expansion portion protrudes upward from the lower expansion portion along the rear-facing face of the member attached to the vehicle body to cover the opening in the member attached to the vehicle body and at least the portion above the protruding opening. The airbag device is enabled to protect the knees of the passenger properly by extending and expanding the airbag efficiently taking into account the time elapsed, until completion of the extension and expansion.

Claims

1. A knee protecting airbag device comprising:

an airbag for inflating, when fed with an inflating gas, to protect the knees of a passenger; and

a housing portion arranged on the lower side of a member attached to the vehicle and in front of the knees of the seated passenger for housing the airbag folded,

wherein said housing portion includes an opening for protruding said airbag toward the vehicle rear,

wherein said airbag is arranged to extend and expand, when fed with said inflating gas, while protruding from said housing portion toward the vehicle rear, and

wherein said airbag includes;

a lower expansion portion which is upstream of said inflating gas flow, for protruding from the opening of said housing portion toward the rear of the vehicle, when fed with said inflating gas, to cover the front sides of said knees; and

an upper expansion portion communicating with said lower expansion portion and being downstream of the gas flow, for protruding upward from said lower expansion portion along the rear-facing face of said member attached to the vehicle to cover the said opening in said vehicle side member and at least the area above protruding opening.

2. A knee protecting airbag device according to claim 1,

wherein said airbag includes a wall arranged on said vehicle side upon completion of the extension and expansion, and a wall on the passenger side opposite said vehicle side wall upon completion of the extension and expansion, and

wherein a tether is arranged in said airbag for connecting said vehicle side wall and said passenger side wall to regulate the thickness of said lower expansion portion when extending and expanding.

3. A knee protecting airbag device according to claim 1,

wherein a flow-directing cloth is arranged in said airbag for guiding said inflating gas from said lower expansion portion to said upper expansion portion.

4. A knee protecting airbag device according to claim 3,

wherein said flow-directing cloth is arranged to guide said inflating gas upward along the rear-facing face of said member attached to the vehicle body.

5. A knee protecting airbag device according to claim 4,

wherein said airbag includes a wall arranged on said vehicle side upon completion of the extension and expansion, and a wall on the passenger side opposite said vehicle side wall upon completion of the extension and expansion,

wherein tethers are arranged in said airbag for connecting said vehicle side wall portion and said passenger side wall portion to regulate the thickness of said lower expansion portion when extending and expanding,

wherein an inflator for discharging said inflating gas is arranged in the lower expansion portion of said airbag,

wherein said tethers are arranged above and below said inflator, and

wherein said flow-directing cloth is formed generally into a sheet shape and supported by said upper and lower tethers.

6. A knee protecting airbag device according to claim 1,

wherein said airbag has a cushioning pad joined to the outer surface side of the passenger side wall at said lower expansion portion, and

wherein said pad is made substantially flush with the peripheral edge of said protruding opening, when said airbag is housed in said housing portion, to clog said protruding opening, and moves, when said airbag is extending and expanding, toward the rear of the vehicle as said lower expansion portion protrudes, so that it is arranged on the front sides of said knees.

7. A knee protecting airbag device according to claim 1,

wherein said airbag includes a wall arranged on said vehicle side upon completion of the extension and expansion, and a wall on the passenger side opposite said vehicle side wall portion upon completion of the extension and expansion, and

wherein said airbag is folded through a step of rolling the upper edge side toward said vehicle side wall portion.

8. A knee protecting airbag device according to claim 1,

wherein said airbag is folded by a cactus folding method to fold the outer peripheral side into said airbag so that it may be housed in said housing portion.

9. A knee protecting airbag device according to claim 1,

wherein said airbag is constructed such that it can cover a hard member arranged on an instrument panel upon completion of the extension and expansion.

10. A knee protecting airbag device according to claim 1,

wherein said airbag is constructed such that its upper end portion upon completion of the extension and expansion has a smaller transverse size than the lower end portion.

11. A knee protecting airbag device according to claim 1,

wherein said airbag is manufactured by cutting material into a three-dimensional shape to match the shape when expanded.

12. A knee protecting airbag device according to claim 1,

wherein at the initial stage of the extension and expansion of said airbag, said lower expansion portion protrudes toward the rear of the vehicle from the protruding opening of said housing portion, and then extends and expands transversely to cover the areas to the left and right of said protruding opening.

13. A knee protecting airbag device according to claim 12,

wherein means for extending and expanding said lower expansion portion transversely includes a gas flow guide member arranged in said airbag for guiding said inflating gas in said lower expansion portion to the two transverse sides.

14. A knee protecting airbag device according to claim 13,

wherein said airbag includes a wall arranged on said vehicle side upon completion of the extension and expansion, and a wall on the passenger side confronting said vehicle side wall upon completion of the extension and expansion,

wherein a tether is arranged in said airbag for connecting said vehicle side wall and said passenger side wall to regulate the thickness of said lower expansion portion when extending and expanding, and

wherein said tether is removed at their left and right ends from the two left and right edges of said airbag and arranged in the transverse directions to construct said gas flow guide member.

15. A knee protecting airbag device according to claim 14,

wherein the tether constructing said gas flow guide member defines a gas communication port near its center for feeding the inflating gas to said upper expansion portion.

16. A knee protecting airbag device according to claim 13,

wherein an inflator for discharging said inflating gas is arranged in the lower expansion portion of said airbag, and

wherein said gas flow guide member is formed in a tubular shape with its two left and right ends opened and covering said inflator.

17. A knee protecting airbag device according to claim 16,

wherein said gas flow guide member has an auxiliary opening at a transverse central portion for feeding the inflating gas to said upper expansion portion.

18. A knee protecting airbag device according to claim 17,

wherein said gas flow guide member has narrow openings at its left and right ends, and

wherein said auxiliary opening is sewn at its peripheral edge with a sewing thread, for allowing said auxiliary opening to open when the thread is broken.

19. A knee protecting airbag device according to claim 12,

wherein an inflator for discharging said inflating gas is arranged near the transverse center in the lower expansion portion of said airbag,

wherein said airbag includes a wall on said vehicle side upon completion of the extension and expansion, and a wall on the passenger side opposite said vehicle side wall upon completion of the extension and expansion,

wherein said passenger side wall is constructed with joining positions between the transverse central portion and the two left and right ends, and

wherein means for extending and expanding said lower expansion portion transversely includes a folded shape resulting from vertical folding step of portions on the two left and right edge sides of said airbag respectively, on the side of the vehicle side wall at said joining positions on the left and right of said passenger side wall portion.