Knee airbag

• US 20090134611A1
• Filed: 10/31/2008
• Published: 05/28/2009
• Est. Priority Date: 11/02/2007
• Status: Active Grant

• Current Assignee: Joyson Safety Systems Acquisition, LLC (Ningbo Junsheng Investment Group Co., Ltd.)
• Original Assignee: TK Holdings Incorporated (Ningbo Junsheng Investment Group Co., Ltd.)
• Inventors: Mendez, Gerardo, Wigger, Henning
• Granted Patent: US 8,096,578 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 2021/23386 External tether means
• CPC Class Codes: B60R 21/231 characterised by their shape, construction or spatial configuration
• CPC Class Codes: B60R 21/2338 Tethers
• CPC Class Codes: B60R 21/2342 Tear seams
• CPC Class Codes: B60R 21/237 characterised by the way they are folded

Abstract

A knee airbag apparatus includes a front panel configured to face toward an occupant when the knee airbag deploys and a rear panel configured to face toward an instrument panel when the knee airbag deploys. The rear panel is joined to the front panel to form an inflatable knee cushion configured to inflate to protect an occupant'"'"'s knees during a crash event. The knee airbag further includes at least one internal tether extending between the front and rear panels. The internal tether is attached to the front panel at a front panel attachment location offset from a rear panel attachment location. The knee airbag further includes an external tether attached at one end to the front panel, and at a second end at the knee airbag housing.

Claims

1. A knee airbag apparatus, comprising:

a front panel configured to face toward an occupant when the knee airbag deploys;

a rear panel configured to face toward an instrument panel when the knee airbag deploys, the rear panel joined to the front panel to form an inflatable knee cushion configured to inflate to protect an occupant'"'"'s knees during a crash event; and

a first internal tether extending between the front and rear panels, the first internal tether attached to the front panel at a front panel attachment location offset from a rear panel attachment location.

2. The knee airbag apparatus of claim 1, further comprising a second internal tether extending between the front and rear panels, the second internal tether being attached to the front panel at a front panel attachment location offset from a rear panel attachment location.

3. The knee airbag apparatus of claim 2, wherein the second internal tether is parallel to the first internal tether.

4. The knee airbag apparatus of claim 2, wherein an offset angle of the first internal tether is different from an offset angle of the second internal tether.

5. The knee airbag apparatus of claim 1, wherein an offset angle of the first internal tether is less than 90 degrees.

6. The knee airbag apparatus of claim 5, wherein the offset angle is in a range of five to 85 degrees.

7. The knee airbag apparatus of claim 2, wherein the first and second internal tethers are configured to shift between the front and rear panels to pull the knee cushion upward against the instrument panel.

8. The knee airbag apparatus of claim 1, wherein the front panel attachment location is offset from the rear panel attachment location by approximately 15 to 60 mm.

9. The knee airbag apparatus of claim 1, wherein the first internal tether has a length in a range of approximately 15 mm to 60 mm.

10. The knee airbag apparatus of claim 9, wherein the first internal tether has an offset angle in a range of nine to 85 degrees.

11. The knee airbag apparatus of claim 1, further comprising an external tether.

12. The knee airbag apparatus of claim 11, wherein the external tether comprises a trapezoidal shape.

13. The knee airbag apparatus of claim 11, wherein the external tether includes at least one frangible portion.

14. The knee airbag apparatus of claim 11, wherein a first end of the external tether is attached to the front panel, and the second end of the external tether is fixed to a housing member.

15. The knee airbag apparatus of claim 14, wherein the first end of the external tether is releasably attached to the front panel.

16. The knee airbag apparatus of claim 14, wherein the first end or a middle portion of the external tether includes a frangible portion configured to release the external tether from the knee airbag.

17. The knee airbag apparatus of claim 1, further comprising a bracket configured to mount the knee airbag in a housing, the housing located in an instrument panel of a vehicle.

18. The knee airbag apparatus of claim 17, wherein a first distance from a center line of the bracket to a seam connecting the front and rear panels at a bottom of the knee cushion is greater than a second distance from the center line of the bracket to a lower edge of the housing.

19. The knee airbag apparatus of claim 1, wherein the front and rear panels are formed of a single sheet.

20. A method of forming a knee airbag, comprising:

joining a front panel to a rear panel to form a knee cushion;

laying the knee cushion flat such that the rear panel is on top of the front panel;

folding the knee cushion, wherein the folding includes rolling the knee cushion beginning at a top end of the knee cushion toward a bottom end of the knee cushion with a mounting bracket;

after rolling the knee cushion toward the bottom end, folding the knee cushion back towards the front end in a Z-type fold.

21. The method of claim 20, wherein the rolling includes five rolls.

22. The method of claim 20, further comprising:

attaching an external tether to the knee cushion.

23. The method of claim 22, wherein attaching the external tether includes:

attaching a first end of the external tether to the front panel; and

folding the knee cushion after attaching the first end of the external tether.

24. The method of claim 23, wherein attaching the external tether further includes:

fixing a second end of the external tether to the mounting bracket, a housing member, or the rear panel of the knee cushion after folding the knee cushion.

25. The method of claim 24, wherein the first end of the external tether is wider than the second end of the external tether.

26. The method of claim 24, wherein fixing of the second end of the external tether occurs after rolling the cushion and before folding the cushion back in a Z-fold.

27. The method of claim 24, wherein fixing of the second end of the external tether occurs after rolling the cushion and after folding the cushion back in a Z-fold.

28. The method of claim 20, further comprising:

tucking sides of the knee cushion into the cushion prior to folding the knee cushion.