GB2446075A

GB2446075A - Airbag with lateral internal tether

Info

Publication number: GB2446075A
Application number: GB0806500A
Authority: GB
Inventors: Yan Fu; Weigang Chen; Baohua Xiao; Marwan Elbkally
Original assignee: Ford Global Technologies LLC
Current assignee: Ford Global Technologies LLC
Priority date: 2005-05-09
Filing date: 2006-05-03
Publication date: 2008-07-30
Anticipated expiration: 2026-05-03
Also published as: GB2446075B; GB0806500D0

Abstract

An airbag restraint 10 for an automotive vehicle, comprises a generally circular front panel 12, a generally circular rear panel 14 mated to said front panel 12, an inflator 16 attached to said rear panel 14 and acting through an inflator aperture formed in said rear panel 14, and at least one internal tether 30, 32, extending laterally along a chord of said front panel 12 and attached to the front and rear panels 12,14 at a common outer periphery 18 of the front and rear panels 12, 14.

Description

AIRBAG RESTRAINT FOR AUTOMOTIVE VEHICLE

The present invention relates to a supplemental restraint system for use in a vehicle. Such restraint systems are commonly called "airbags." According to the present invention, there is provided an airbag restraint for an automotive vehicle as set forth in claim 1 of the appended claims.

As shown in FIG. 3, a prior art airbag, 600, for use at the driver's position of a vehicle, commonly uses two longitudinal tethers, 602, which are generally located about the hub of steering wheel 606 at clock positions, 12 o'clock and 6 o'clock. The present inventors have determined that for certain vehicles, it is desirable to reshape the inflated airbag in a manner not comprehended by the prior art, by using laterally extending tethered sections of the

airbag, as opposed to the prior art's superimposed

longitudinal tethering structures. Although the prior art is replete with a variable plethora of tethering schemes, none restricts airbag lateral deployment and longitudinal deployment in the manner provided by the structures according to the present invention. These structures result in more favourable energy management and loading kinematics during a vehicle impact event.

In the preferred embodiments of the present invention, an airbag restraint for an automotive vehicle includes a generally circular front panel, a generally circular rear panel mated to the front panel, and an inflator attached to the rear panel and acting through an inflator aperture formed in the rear panel. The internally tethered section is preferably generated by a plurality of internal, longitudinal tethers attached to both the rear panel and the front panel. Each tether extends laterally along a portion of the previously described chord of the front panel. Taken together, the ends of the tethers which are attached to the front panel encompass at least about one-half the length of a chord extending laterally across the front panel.

Alternatively, the internally tethered section may be generated by more than one internal laterally extending tether positioned at a number of parallel chordal locations, with each of the tethers being attached to the front and rear panels at the common outer periphery of the front and rear panels. The internally tethered section will be generated by a plurality of unequal length laterally extending tethers positioned at two chordal locations, with each of the tethers being attached to the front and rear panels at the front and rear panels' common outer periphery.

The invention may further include at least one additional interior longitudinal tether attached to and extending laterally across a portion of the front and rear panels at a location between the inflator aperture and the longest of the plurality of laterally extending tethers.

It is an advantage of the invention that the airbag is preferentially reshaped from basically a toroidal shape to a more complex shape characterized by greater volume of the airbag at an lower portion of the deployed airbag and lesser volume at an upper portion of the airbag.

The invention will now be described further, by way of example, with reference to the accompanying drawings, in which: Figure 1 illustrates a second embodiment of an airbag of the invention and shown in an inflated state.

Figure 2 illustrates a simulated occupant-airbag interaction with the airbag of Figure 4.

Figure 3 shows a prior art airbag.

As shown in FIG. 1, airbag restraint 10 has a generally circular front panel 12, stitched to a rear panel 14. Airbag inflates through the circular portion of steering wheel 40. The present airbag utilizes an internally tethered section generated by first lateral tether 30 and second lateral tether 32. Tethers 30 and 32 are generally parallel, and extend across parallel chords of airbag 10.

Each of tethers 30 and 32 is formed, from a strap of airbag material, which is sewn at its ends into the front panel 12 and rear panel 14 at their common outer periphery, 18.

In addition to lateral tethers 30 and 32, FIG. 1 also shows a longitudinal tether, 36, which is sewn into front panel 12 and rear panel 14 at a location above inflator 16.

Thus, the airbag of FIG. 1 is a hybrid airbag because it utilizes both laterally extending tether webs 30 and 32 and a longitudinally extending tether web 36. In general, the longitudinal tether 36 of FIG. 1 may extend laterally (by virtue of its width) across a portion of front and rear panels 12 and 14 at a location between inflator aperture 24 and the longest one, i.e., 32, of the laterally extending tether webs.

FIG. 2 illustrates an interaction between a simulated occupant, 44, seated on seat 46, and inflated airbag 10, according to FIG. 1. It is noted that the construction of FIG. 1 produces a tethered airbag shape in which the volume of the airbag is shifted downwardly, so as to provide a larger volume for reacting to the upper torso of the simulated occupant.

Claims

1. An airbag restraint for an automotive vehicle, comprising: a generally circular front panel (12); a generally circular rear panel (14) mated to said front panel; an inflator (16) attached to said rear panel and acting through an inflator aperture formed in said rear panel; and at least one internal tether (30) extending laterally along a chord of said front panel and attached to the front and rear panels at a common outer periphery (18) of the front and rear panels (12,14).

2. An airbag restraint as claimed in Claim 1, wherein said at least one tether comprises a plurality of unequal length, laterally extending tethers positioned at two chordal locations, with each of said tethers being attached to said front and rear panels at their common outer periphery.

3. An airbag restraint as claimed in claim 2, wherein the plurality of chords are parallel to one another.

4. An airbag restraint as claimed in Claims 1 to 3, further comprising at least one additional internal longitudinal tether attached to, and extending laterally across, a portion of said front and rear panels at a location between said inflator aperture and the shortest one of said plurality of laterally extending tethers.

5. An airbag restraint as claimed in any of Claims 1 to 4, wherein each of tether comprises a length of airbag material.

6. An airbag restraint as claimed in any preceding claim, further comprising a steering column upon which said front panel, said rear panel, and said inflator are mounted.