Airbag inflation tunnels and related systems and methods

Airbag cushion assemblies comprising an airbag inflation tunnel positioned within an airbag cushion. Some embodiments may comprise an airbag cushion comprising an inflator opening and an airbag inflation tunnel coupled to the airbag cushion. The inflation tunnel may be configured to direct inflation gas from an inflator positioned within the inflator opening down the airbag inflation tunnel upon deployment of the inflator. A plurality of directional vent openings may be positioned within the airbag inflation tunnel that may be configured to direct the inflation gas laterally relative to the inflator. The inflation tunnel may further be configured such that the inflation gas contacts a terminal end of the inflation tunnel prior to exiting the plurality of directional vent openings.

SUMMARY

Airbag cushion inflation often results in cushion “bounce.” In other words, for driver-side airbags, for example, the forces associated with airbag inflation often cause the cushion to deflect off of the steering wheel and deliver high forces directly towards a driver. In addition, airbags often inflate by inflating the central part of the cushion before the lateral sides of the cushion.

The present inventors have therefore determined that it would be desirable to provide systems and methods that overcome one or more of the foregoing limitations and/or other limitations of the prior art by, in some embodiments, providing airbag cushion assemblies that include an inflation tunnel that may allow inflation gas to fill the cushion radially or laterally during an earlier stage of inflation. Such radial inflation and/or other beneficial aspects of one or more embodiments disclosed herein may reduce forces delivered to an occupant, reduce cushion bounce, reduce occupant travel during a vehicle crash, provide a more desirable foundation for the airbag during an early stage of deployment, and/or otherwise improve upon the prior art. Various airbag inflation tunnels disclosed herein may also, or alternatively, act as inflation tethers, control airbag deployment distances, reduce fabric uses and/or costs, and/or allow for tuning of airbag deployment characteristics.

In a more particular example of an airbag cushion assembly according to some embodiments, the assembly may comprise an airbag cushion comprising an inflator opening. The assembly may further comprise an airbag inflation tunnel coupled to the airbag cushion about the inflator opening. The inflation tunnel may be configured to direct inflation gas from an inflator positioned within the inflator opening down the airbag inflation tunnel upon deployment of the inflator. The inflation tunnel may further be configured to at least substantially prevent the inflation gas from being directed laterally within the airbag cushion immediately adjacent to the inflator such that the inflation gas must travel within the airbag inflation tunnel upon deployment of the inflator prior to entering a primary inflation chamber of the airbag cushion. The inflation tunnel may further comprise a plurality of directional vent openings positioned within the airbag inflation tunnel configured to direct the inflation gas laterally relative to the inflator. The inflation tunnel may further be configured such that the inflation gas contacts a terminal end of the inflation tunnel prior to exiting the plurality of directional vent openings.

In some embodiments, the inflation tunnel may comprise a base configured to define a full perimeter adjacent to the inflator so as to prevent the inflation gas from being directed laterally within the airbag cushion immediately adjacent to the inflator.

In some embodiments, at least a subset of the plurality of directional vent openings may be evenly distributed from a cross-sectional view of the inflation tunnel taken perpendicular to an elongated length of the inflation tunnel. In some such embodiments, the plurality of directional vent openings may comprise a first set of vent openings extending along the length of the inflation tunnel; a second set of vent openings extending along the length; and a third set of vent openings extending along the length, wherein the first set of vent openings is spaced from the second set of vent openings by at least about 120 degrees from the cross-sectional view, wherein the second set of vent openings is spaced from the third set of vent openings by at least about 120 degrees from the cross-sectional view, and wherein the third set of vent openings is spaced from the first set of vent openings by at least about 120 degrees from the cross-sectional view. Of course, a variety of alternative embodiments and implementations are contemplated, including but not limited to providing a first set of vent openings and a second set of vent openings spaced by about 180 degrees relative to the first set, or the holes may be grouped together more closely, depending upon the desired deployment characteristics.

In some embodiments, the inflation tunnel may be directly coupled to an inner surface of the airbag cushion. Alternatively, a tether may be coupled to an inner surface of the airbag cushion and coupled to the inflation tunnel. In some such embodiments, the tether may be coupled to an inner surface of the airbag cushion directly opposite from the inflator such that the tether is configured to be at least substantially aligned with the inflation tunnel during inflation of the airbag cushion.

In some embodiments, the inflation tunnel may be defined by a rectangular panel. In implementations of methods for manufacturing such an inflation tunnel, opposing sides of the panel may be aligned and sewn or otherwise coupled together to define a tubular structure. In some such embodiments and/or implementations, a flap may be sewn to one end of the tubular structure to define a closed terminal end.

In some embodiments, the inflation tunnel may comprise a base and a closed tip opposite from the base, and the inflation tunnel is configured such that, upon inflation of the airbag cushion, the inflation gas is forced to contact the closed tip before exiting the inflation tunnel. In some embodiments, the inflation tunnel may comprise a length between the base and the tip, and the length may be between about 200 mm and about 300 mm.

In another specific example of an airbag cushion assembly according to other embodiments, the assembly may comprise an airbag cushion comprising an inflator opening. The assembly may further comprise an elongated airbag inflation tunnel coupled to the airbag cushion. The airbag inflation tunnel may comprise a base and a tip opposite from the base along a length of the airbag inflation tunnel, wherein the airbag inflation tunnel is coupled to the airbag cushion along the base. The airbag inflation tunnel may be configured to direct inflation gas from an inflator positioned within the inflator opening down the airbag inflation tunnel upon deployment of the inflator. In some embodiments, the tip may comprise a first width in a direction perpendicular from the length, and the base may comprise a second width in a direction perpendicular from the length, wherein the second width is greater than the first width. For example, in some such embodiments, the inflation tunnel may taper from the base to the tip, such as a closed tip in some embodiments, such that a width of the inflation tunnel gradually decreases from the base to the tip, or at least along a portion of the length between the base and the tip.

Some embodiments may further comprise a plurality of directional vent openings positioned within the airbag inflation tunnel. In some embodiments, the inflation tunnel may be configured to at least substantially prevent the inflation gas from being directed laterally within the airbag cushion immediately adjacent to the inflator such that the inflation gas must travel within the airbag inflation tunnel upon deployment of the inflator prior to entering a primary inflation chamber of the airbag cushion. The plurality of directional vent openings may be configured to distribute inflation gas laterally relative to the inflator and symmetrically from a cross-sectional view of the inflation tunnel taken perpendicular to the length of the inflation tunnel. In some such embodiments, the plurality of directional vent openings may comprise a first set of vent openings; a second set of vent openings; and a third set of vent openings, wherein the first set of vent openings is spaced from the second set of vent openings by at least about 120 degrees from the cross-sectional view, wherein the second set of vent openings is spaced from the third set of vent openings by at least about 120 degrees from the cross-sectional view, and wherein the third set of vent openings is spaced from the first set of vent openings by at least about 120 degrees from the cross-sectional view.

In some embodiments, the inflation tunnel may comprise a frusto-conical shape.

The inflation tunnel may be configured such that, upon inflation of the airbag cushion, the inflation gas is forced to contact the closed tip before exiting the inflation tunnel.

Some embodiments may further comprise a cover configured to receive the airbag cushion. The cover may comprise a tear seam, and the airbag cushion may be positioned within the cover such that the inflation tunnel contacts the tear seam upon deployment of the airbag cushion to facilitate separation of the tear seam.

In another specific example of an airbag cushion assembly according to another embodiment, the assembly may comprise an airbag cushion comprising an inflator opening. The airbag cushion may define a primary inflation chamber. The assembly may further comprise an inflator extending into the inflator opening and an elongated airbag inflation tunnel coupled to the airbag cushion. The airbag inflation tunnel may be defined by a rectangular panel, and may comprise a base and a closed tip opposite from the base. The airbag inflation tunnel may be coupled to the airbag cushion along the base, and may be configured to direct inflation gas from the inflator down the airbag inflation tunnel upon deployment of the inflator. The inflation tunnel may further taper from the base to the tip such that a width of the inflation tunnel gradually decreases from the base to the tip. The inflation tunnel may further be configured to at least substantially prevent the inflation gas from being directed laterally within the airbag cushion immediately adjacent to the inflator such that the inflation gas must travel within the airbag inflation tunnel upon deployment of the inflator prior to entering the primary inflation chamber, and such that, upon inflation of the airbag cushion, the inflation gas is forced to contact the closed tip before exiting the inflation tunnel. The assembly may further comprise a plurality of directional vent openings positioned within the airbag inflation tunnel, wherein the plurality of directional vent openings are configured to distribute inflation gas from the inflator laterally relative to the inflator and symmetrically from a cross-sectional view of the inflation tunnel taken perpendicular to a length of the inflation tunnel extending between the base and the tip.

The features, structures, steps, or characteristics disclosed herein in connection with one embodiment may be combined in any suitable manner in one or more alternative embodiments.

DETAILED DESCRIPTION

A detailed description of apparatus, systems, and methods consistent with various embodiments of the present disclosure is provided below. While several embodiments are described, it should be understood that the disclosure is not limited to any of the specific embodiments disclosed, but instead encompasses numerous alternatives, modifications, and equivalents. In addition, while numerous specific details are set forth in the following description in order to provide a thorough understanding of the embodiments disclosed herein, some embodiments can be practiced without some or all of these details. Moreover, for the purpose of clarity, certain technical material that is known in the related art has not been described in detail in order to avoid unnecessarily obscuring the disclosure.

Apparatus, methods, and systems are disclosed herein relating to airbag cushion assemblies including airbag inflation tunnels. Such tunnels may be configured to improve airbag cushion deployment characteristics, such as by reducing loads on occupants during deployment, reduce cushion “bounce,” control deployment distances, etc.

The embodiments of the disclosure may be best understood by reference to the drawings, wherein like parts may be designated by like numerals. It will be readily understood that the components of the disclosed embodiments, as generally described and illustrated in the figures herein, could be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of the embodiments of the apparatus and methods of the disclosure is not intended to limit the scope of the disclosure, as claimed, but is merely representative of possible embodiments of the disclosure. In addition, the steps of a method do not necessarily need to be executed in any specific order, or even sequentially, nor need the steps be executed only once, unless otherwise specified. Additional details regarding certain preferred embodiments and implementations will now be described in greater detail with reference to the accompanying drawings.

FIG. 1depicts an airbag cushion assembly100according to some embodiments. Airbag cushion assembly100comprises an airbag cushion110. Airbag cushion110comprises an opening112, which may be configured to receive an inflator50therethrough for inflation of airbag cushion110.

Airbag cushion assembly100further comprises an airbag inflation tunnel120coupled to the airbag cushion110about the inflator opening112. Inflation tunnel120may be configured to direct inflation gas from an inflator50positioned within the inflator opening112down the airbag inflation tunnel120upon deployment of the inflator50. In some embodiments, inflation tunnel120may be configured to at least substantially prevent the inflation gas from being directed laterally within the airbag cushion110immediately adjacent to the inflator and/or inflator opening112such that the inflation gas must travel within the airbag inflation tunnel120upon deployment of the inflator50prior to entering a primary inflation chamber114of airbag cushion110.

Thus, as best seen inFIGS. 1 and 2, upon entering airbag inflation tunnel120, inflation gases cannot immediately enter primary inflation chamber114. In the depicted embodiment, this is caused at least in part because the inflation tunnel120comprises a base125that defines a full perimeter adjacent to the inflator50and/or the opening112so as to prevent the inflation gas from being directed laterally within the airbag cushion immediately adjacent to the inflator50.

Airbag inflation tunnel120comprises a plurality of directional vent openings122positioned within the airbag inflation tunnel120. In the depicted embodiment, the plurality of directional vent openings122are configured to direct the inflation gas laterally relative to the inflator50. In some embodiments, the airbag inflation tunnel120and vent openings122may be configured such that the inflation gas is at least substantially prevented from directly contacting a portion of the airbag cushion110directly opposite from the inflator50. Thus, in some such embodiments, airbag inflation tunnel120may comprise a closed terminal end126. As described in greater detail below, in some embodiments, airbag inflation tunnel120may comprise a closed flap defining terminal end126. In some embodiments, including the embodiment ofFIGS. 1-3, inflation tunnel120is configured such that the inflation gas contacts terminal end126of inflation tunnel120prior to exiting the plurality of directional vent openings122. Embodiments comprising a closed terminal end may be configured such that, upon inflation of the airbag cushion, the inflation gas is forced to contact the closed tip before exiting the inflation tunnel (through the vent openings).

This may be useful for improving a variety of deployment conditions/problems, including, for example, reducing cushion “bounce,” or the phenomenon of the cushion rebounding and contacting the steering wheel (for driver-side airbags) during and/or after inflation. Similarly, this may reduce forces experienced by a driver or other passenger during airbag deployment. In addition, this may provide for a more desirable foundation for airbag deployment, since the cushion will tend to deploy radially rather than directly contacting the occupant, in some embodiments closer to the deployment module, which may allow the cushion to be in better position and/or condition to receive the force of the occupant during deployment.

In some embodiments, the inflation tunnel, such as inflation tunnel120, may comprise a length between the base and the tip, such as between base125and terminal, closed end126that may be between about 200 mm and about 300 mm in length. This length, however, may vary depending upon a wide variety of factors, including whether there is a terminal tether present, which will be discussed below in connection withFIG. 5.

In some embodiments, the inflation tunnel may be directly coupled to an inner surface of the airbag cushion. Thus, in the depicted embodiment, closed terminal end126of inflation tunnel120is directly sewn or otherwise coupled to the interior surface of airbag cushion110at128. In this manner, inflation tunnel120may serve to limit the deployment length of airbag cushion110from inflator50towards the occupant. As described below, however, other embodiments are contemplated in which the inflation tunnel is indirectly coupled to the airbag cushion, such as by use of a terminal tether that may, for example, extend from a tip of the inflation tunnel to an interior surface of the airbag cushion opposite from the inflator. Still other embodiments are contemplated in which the inflation tunnel is closed only by virtue of its being coupled to the inside of an airbag cushion. In other words, some embodiments may lack a flap to close the terminal end. However, it may be preferred to provide such a flap to increase the strength of the cushion/tunnel at its terminal end where inflation gases will be expected to deliver the strongest forces.

Some embodiments may comprise various tethers, some of which may be lateral tethers coupled to a lateral surface of the inflation tunnel, either in addition to, or instead of a terminal tip tether, as previously mentioned. For example,FIGS. 1-3depict various lateral tethers140a,140b, and140c, each of which is coupled to a lateral, internal surface of airbag cushion110at one end, and is coupled to a lateral surface of inflation tunnel120at its respective opposite end. Such tethers may allow for further tuning of desired airbag deployment characteristics.

In some embodiments, assembly100may further comprise a cover150, which may be configured to receive airbag cushion110and from which airbag cushion110may be deployed, as shown inFIG. 2. In some such embodiments, the cover150may comprise a tear seam155, and the airbag cushion110may be positioned within the cover150such that the inflation tunnel120will contact (typically indirectly) the tear seam155upon deployment of the airbag cushion110to facilitate separation of the tear seam155. In other words, the directional force of inflation gas towards a particular location within airbag cushion110may also be used to separate a cover tear seam155by appropriately aligning the tear seam155with the expected location of airbag inflation tunnel120during deployment.

In some embodiments, lateral tethers140may be evenly spaced about the periphery of airbag inflation tunnel120. For example, as shown in the cross-sectional view ofFIG. 3, some embodiments may comprise three tethers spaced apart from one another by about 120 degrees from one another. However, other embodiments are contemplated in which different number of lateral tethers, or no tethers at all may be present. For example, in another contemplated embodiment, two lateral tethers may be used, each of which extends laterally from the other tether in an at least approximately opposite direction such that the tethers are spaced apart from one another radially by about 180 degrees.

Various sets of aligned vent openings may be similarly spaced apart from one another. For example, as also best shown inFIG. 3, several sets of vent openings are shown evenly distributed from a cross-sectional view of inflation tunnel120taken perpendicular to an elongated length of the inflation tunnel120. More particularly, a first set of directional vent openings122a, a second set of vent openings122b, a third set of vent openings122c, a fourth set of vent openings122d, a fifth set of vent openings122e, and a sixth set of vent openings122f, each respectively extends along an elongated length of the inflation tunnel120. Each of the various sets of vent openings is spaced apart from one another by about sixty degrees. Each of the various sets of vent openings may comprise a single vent opening or, alternatively may comprise a plurality of aligned vent openings extending at the same, or at least approximately the same, angle as the other vent openings in the set.

In other embodiments, other numbers of vent opening sets may be used. For example, in another preferred embodiment, three sets of vent openings may extend along the length of the inflation tunnel. In some such embodiments, the first set of vent openings is spaced from the second set of vent openings by at least about 120 degrees from the cross-sectional view, the second set of vent openings is spaced from the third set of vent openings by at least about 120 degrees from the cross-sectional view, and the third set of vent openings is spaced from the first set of vent openings by at least about 120 degrees from the cross-sectional view.

FIGS. 4A and 4Bdepict exemplary steps in an example of a method for manufacturing an airbag inflation tunnel120according to certain preferred embodiments and/or implementations.FIG. 4Adepicts airbag inflation tunnel120comprising terminal flap126and rectangular panel128. In a method step preliminary to the stage depicted inFIG. 4A, vent openings122may be formed. Of course, vent openings122may instead be formed during a later step if desired.

Following the stage depicted inFIG. 4A, rectangular panel128may be rolled or folded such that its opposing ends are aligned and then sewn or otherwise coupled together to define a tubular structure. Flap126may then be sewn to one end of rectangular panel128to define a closed terminal end, as previously mentioned. In alternative implementations, airbag inflation tunnel120may lack flap126and may instead be sewn or otherwise coupled directly to an interior surface of an airbag cushion, as previously mentioned.

AlthoughFIGS. 4A and 4Bdepict the manufacture of an airbag inflation tunnel120defining a cylindrical tubular structure having an approximately constant cross-sectional diameter along its length between its base and its terminal end, other embodiments having different shapes and/or sizes are contemplated. For example, in some embodiments, as discussed below in connection withFIG. 5, the airbag inflation tunnel may comprise a tapering width extending along its length so as to, for example, define a frusto-conical shape.

FIG. 5depicts another airbag cushion assembly500according to some embodiments. Airbag cushion assembly500comprises an airbag cushion510comprising an opening512, which may be configured to receive an inflator50therethrough for inflation of airbag cushion510.

Airbag cushion assembly500further comprises an airbag inflation tunnel520coupled to the airbag cushion510about the inflator opening512. Inflation tunnel520differs from the previously-depicted inflation tunnels in that it tapers in cross-sectional diameter. More particularly, inflation tunnel520comprises a narrow, closed terminal end526that increases in width towards base525. Base525defines a full perimeter adjacent to the inflator50and opening512so as to prevent the inflation gas from being directed laterally within the airbag cushion immediately adjacent to inflator50. Although it may be preferred for some applications that this tapering extend from a wider diameter at or near the base of the airbag inflation tunnel, such as is depicted inFIG. 5, alternative embodiments are contemplated in which this tapering may extend in an opposite direction. However, it is preferred for most applications that the airbag inflation tunnel either taper from wide to narrow towards the tip, at least in part, or otherwise have a narrower tip than base, or that the airbag inflation tunnel have a constant diameter. In some embodiments, the airbag inflation tunnel may comprise a length extending between a base and a tip. The tip may comprise a first width in a direction perpendicular from the length, and the base may comprise a second width in a direction perpendicular from the length. In some such embodiments, the second width may be greater than the first width.

Assembly500further differs from the previously-depicted embodiments in that a terminal tether545is provided that couples the terminal end526of airbag inflation tunnel520to an interior surface of airbag cushion510at stitch line528. Of course, terminal tether545may be coupled to airbag cushion510by alternative means if desired. Preferably, terminal tether545is coupled to a region of airbag cushion510that is directly opposite that of inflator50such that, in some embodiments, the location of this coupling528is at a center location, or at least approximately a center location, of airbag cushion510. In addition, terminal tether545is coupled to an inner surface of airbag cushion510directly opposite from inflator50such that tether545is at least substantially aligned with a central axis of inflation tunnel520during inflation of airbag cushion510, as shown inFIG. 5.

Assembly500is otherwise similar to the previously-depicted embodiments. For example, airbag inflation tunnel520again comprises a plurality of directional vent openings522positioned within the airbag inflation tunnel520, which are configured to direct inflation gas laterally relative to inflator50. Also, airbag inflation tunnel520and vent openings522are configured such that the inflation gas is at least substantially prevented from directly contacting a portion of the airbag cushion510directly opposite from inflator50, due to closed terminal end526. Inflation tunnel520is therefore configured such that the inflation gas contacts terminal end526of inflation tunnel520prior to exiting the plurality of directional vent openings522.

Assembly500may further comprise one or more lateral tethers, such as tethers540aand540b, which may be coupled to a lateral surface of the inflation tunnel520at one end and a lateral, internal surface of airbag cushion510at an opposite end.

In some embodiments, assembly500may further comprise a cover550, which may comprise a tear seam555. As previously mentioned, airbag cushion510may be positioned within cover550such that the inflation tunnel520will contact tear seam555upon deployment of the airbag cushion510to facilitate desired separation of tear seam555.

The foregoing specification has been described with reference to various embodiments and implementations. However, one of ordinary skill in the art will appreciate that various modifications and changes can be made without departing from the scope of the present disclosure. For example, various operational steps, as well as components for carrying out operational steps, may be implemented in various ways depending upon the particular application or in consideration of any number of cost functions associated with the operation of the system. Accordingly, any one or more of the steps may be deleted, modified, or combined with other steps. Further, this disclosure is to be regarded in an illustrative rather than a restrictive sense, and all such modifications are intended to be included within the scope thereof. Likewise, benefits, other advantages, and solutions to problems have been described above with regard to various embodiments. However, benefits, advantages, solutions to problems, and any element(s) that may cause any benefit, advantage, or solution to occur or become more pronounced, are not to be construed as a critical, required, or an essential feature or element.