Abstract:
A deployment flap can be used with inflatable airbag to reduce the risk of the airbag getting caught between the instrument panel of a vehicle and an out of position occupant. The manner in which the airbag and deployment flap are folded prior to deployment alters their deployment characteristics, such as trajectory.

Description:
TECHNICAL FIELD 
     The present disclosure relates generally to the field of automotive protective systems. More specifically, the present disclosure relates to inflatable airbag cushions with a deployment flap, which is folded according to a predetermined method. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present embodiments will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. Understanding that the accompanying drawings depict only typical embodiments, and are, therefore, not to be considered to be limiting of the disclosure&#39;s scope, the embodiments will be described and explained with specificity and detail in reference to the accompanying drawings. 
         FIG. 1  is a perspective view of an inflatable airbag with a deployment flap, wherein the airbag comprises a portion of an airbag assembly. 
         FIG. 2  is a cross-sectional view of the airbag assembly of  FIG. 1 , wherein the airbag is in a deployed and inflated configuration within a vehicle. 
         FIG. 3  is a side perspective view of the airbag assembly of  FIG. 2 , wherein the assembly is mounted in a vehicle and is depicted in a deployed and inflated configuration within a vehicle. 
         FIG. 4  is a top elevation view of the airbag assembly of  FIG. 2  before the airbag and deployment flap have been folded. 
         FIG. 5  is a cross-sectional view of the airbag assembly of  FIG. 4 . 
         FIG. 6  is a top elevation view of the airbag assembly of  FIG. 4  after side portions of the airbag has been folded inwardly. 
         FIG. 7  is a top elevation view of the airbag assembly of  FIG. 6  after a bottom portion of the airbag has been folded upwardly. 
         FIG. 8  is a cross-sectional view of the airbag assembly of  FIG. 7 . 
         FIG. 9  is a cross sectional view of the airbag assembly of  FIG. 8  after the bottom portion has been forward-rolled. 
         FIG. 10  is a cross-sectional view of the airbag assembly of  FIG. 9  after the forward-rolled bottom portion has been placed within an airbag housing. 
         FIG. 11  is a top elevation view of the airbag assembly of  FIG. 10 . 
         FIG. 12  is a cross-sectional view of the airbag assembly of  FIG. 11  after a top portion of the airbag has been accordion-folded. 
         FIG. 13A  is a cross-sectional view of the airbag assembly of  FIG. 12  after a deployment flap has been accordion-folded. 
         FIG. 13B  is a cross-sectional view of the airbag assembly of  FIG. 13A  after another accordion-fold has been formed in the deployment flap. 
         FIG. 13C  is a cross-sectional view of the airbag assembly of  FIG. 13B  after another accordion-fold has been formed in the deployment flap. 
         FIG. 13D  is a cross-sectional view of the airbag assembly of  FIG. 13C  after the accordion-folded deployment flap has been folded. 
         FIG. 13E  is a top elevation view of a portion of the airbag assembly of  FIG. 13D . 
         FIG. 13F  is a cross-sectional view of the airbag assembly of  FIG. 13D  after a wrapper has been wrapped around the packaged airbag. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     It will be readily understood that the components of the 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 more detailed description of various embodiments, as represented in the figures, is not intended to limit the scope of the disclosure, as claimed, but is merely representative of various embodiments. While the various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated. 
     The phrases “connected to,” “coupled to” and “in communication with” refer to any form of interaction between two or more entities, including mechanical, electrical, magnetic, electromagnetic, fluid, and thermal interaction. Two components may be coupled to each other even though they are not in direct contact with each other. The term “abutting” refers to items that are in direct physical contact with each other, although the items may not necessarily be attached together. 
     Inflatable airbag systems are widely used to minimize occupant injury in a collision scenario. Airbag modules have been installed at various locations within a vehicle, including, but not limited to, the steering wheel, the instrument panel, within the side doors or side seats, adjacent to roof rail of the vehicle, in an overhead position, or at the knee or leg position. In the following disclosure, “airbag” may refer to an inflatable curtain airbag, overhead airbag, front airbag, or any other airbag type. 
     Front airbags are typically installed in the steering wheel and instrument panel of a vehicle. During installation, the airbags are rolled, folded, or both, and are retained in the rolled/folded state behind a cover. During a collision event, vehicle sensors trigger the activation of an inflator, which rapidly fills the airbag with inflation gas. Thus the airbag rapidly changes confirmations from the rolled/folded configuration to an expanded configuration. 
       FIG. 1  is a perspective view of a portion of an inflatable airbag assembly  100 , which may comprise an inflatable airbag  110 , a throat flap  120 , a wrapper  130 , and a deployment flap  140 . Airbag  110  may comprise a throat portion  111  that has an inflator aperture  112 , which is contiguous with an inflatable void  113  and may be coupled to a housing (not shown) via mounting structures  114 . Inflatable airbag  110  also comprises a front face  115 , a top face  117  a bottom face  116 , a side face  118 , and a vent  119 . Top face  117  of cushion  110  is the portion of the cushion that is closest to the headliner of a vehicle when the cushion is in a deployed state. Bottom face  116  is below top face  117  when cushion  110  is in a deployed state, and is closest to a floor of the vehicle. The term “bottom face” is not necessarily limited to the portion of cushion  110  that is below a horizontal medial plane of the cushion, but may include less than half, more than half or exactly half of the bottom portion of the cushion. Likewise, the term “top face” is not necessarily limited to the portion of cushion  110  that is above a horizontal medial plane of the cushion, but may include less than half, more than half or exactly half of the top portion of the cushion. 
     Throat flap  120  is an optional component of assembly  100  and may be used to reinforce airbag  110  at the housing mounting structures  114 , as well as protect portions of airbag  110  during deployment. Throat flap  120  may comprise a throat proximal portion  121  that has an aperture  122  that coincides with inflator aperture  112 . Throat flap  120  also has a throat-distal portion  123  that ends with a distal edge  124 . Throat flap  120  may be coupled to airbag  110  via stitching  125 , which in the depicted embodiment circumnavigates aperture  122 . 
     Wrapper  130  may comprise a frangible material, or a non-frangible material that has been rendered frangible via a rupture point that can comprise perforations or a weakened portion. Wrapper  130  may comprise a throat-proximal portion  131  that terminates in a throat-proximal edge  132  and a throat-distal portion  133  that terminates in a throat-distal edge  134 . Wrapper  130  is configured to wrap around a packaged inflatable airbag and aid in retaining the airbag within the airbag housing. 
     Deployment flap  140  may comprise the same material from which airbag  110  is formed. Deployment flap  140  is configured to deploy in front of airbag  110  and aid in keeping airbag  110  from getting trapped between an out of position occupant, such as a child in a child car seat and the instrument panel in which the airbag is mounted. Deployment flap  140  may comprise a throat-proximal portion  141  that terminates in a throat-proximal edge  142 , and a throat-distal portion  143  that terminates in a throat-distal edge  144 ; deployment flap  140  also comprises lateral sides  145 . 
     In the depicted embodiment, wrapper  130  and deployment flap  140  are coupled to airbag  110  via throat flap  120 . However, in other embodiments, the wrapper and deployment flap may be directly attached to the airbag. Wrapper  130  and deployment flap  140  may be coupled together at their throat-proximal portions  131  and  141  and may be coupled to airbag  110  via stitching  105 . In other embodiments, the wrapper and deployment flap may not be coupled together. The relative sizes and shapes of the airbag, wrapper, and deployment flap as depicted in  FIG. 1  are for illustrative purposes only, and may vary. 
     Those skilled in the art will appreciate that a variety of types and configurations of inflatable airbags can be utilized without departing from the scope and spirit of the present disclosure. For example, the size, shape, and proportions of the cushion membrane may vary according to its use in different vehicles or different locations within a vehicle. Also, the inflatable airbag cushion membrane may comprise one or more pieces of any material well known in the art, such as a woven nylon fabric. Additionally, the airbag cushion may be manufactured using a variety of techniques such as one piece weaving, “cut and sew”, or a combination of the two techniques. Further, the cushion membrane may be manufactured using sealed or unsealed seams, wherein the seams are formed by stitching, adhesive, taping, radio frequency welding, heat sealing, or any other suitable technique or combination of techniques. The inflatable airbag may comprise one or more vents, which may be configured as discreet vents or dynamic vents. Generally, discreet vents do not change diameter during airbag deployment, and may not vary their capacity to vent inflation gas out the inflatable void of the airbag may not change during deployment. Dynamic vents may change diameter during airbag deployment and may vary their capacity to vent inflation gas out the inflatable void of the airbag may not change during deployment. 
       FIG. 2  is a cross-sectional view of airbag assembly  100 , wherein the assembly is mounted within a vehicle instrument panel, and airbag  110  is in a deployed and inflated configuration. Airbag  110  is configured to be coupled to an airbag housing  150  via an inflator  160  at throat portion  111  of the airbag. Inflator  160  is configured to fill inflatable void  118  with inflation gas in response to predetermined conditions. Inflatable void  118  may be defined by throat portion  111 , front face  115 , top face  116 , bottom face  117 , and side faces (not shown). In the deployed and inflated configuration, throat flap  120  is configured to be located between throat portion  111  and a cabin sidewall  151  of housing  150 . Throat proximal portions  131  and  141  of wrapper  130  and deployment flap  140  are coupled to throat-distal portion  123  of throat flap  120  via stitching  105 . 
     Wrapper  130  is configured to be wrapped around the packaged inflatable airbag  110 , such that throat proximal portion  131  is located on one side of the airbag, and throat distal portion  133  is on another side of the airbag. Throat-distal portion  133  is configured to be coupled to a windshield sidewall  152  of housing  150 . Wrapper  130  is configured to rupture during airbag  110  deployment, such that in the deployed configuration, wrapper  130  is torn in at least two pieces, such that throat-proximal portion  131  is on one side of airbag  110  and throat-distal portion  133  is on another side of the airbag. 
     Airbag  110  is configured to deploy out of a top side  153  of airbag housing  150  and extend upward and outward toward a cabin of a vehicle. Deployment flap  140  is configured to precede airbag  110  during deployment, such that distal portion  143  initially deploys in front of front face  115  and upon full deployment, the deployment flap is located below bottom face  117  of the airbag. Upon full deployment, distal edge  144  of deployment flap  140  may extend a distance from airbag housing  150  that is similar to front face  115 . 
       FIG. 3  is a side perspective view of airbag assembly  100 , wherein housing  150  has been mounted in an instrument panel  12  of a vehicle  10 . A child in a child car seat  16  is located on occupant seat  18 , and represents an out-of-position-occupant, which may also be called an “obstruction.” Other obstructions may include a child or adult seated too close to instrument panel  12 . Airbag  110  is depicted in a deployed configuration, wherein the airbag is coupled to housing  150 , and front face  115  is extending into the cabin of a vehicle. Side face  118  of airbag  110  is depicted as having a vent  119 . Deployment flap  140  is depicted as being between the out of position occupant and bottom face  117  of airbag  110 . Deployment flap  140  is configured such that throat-distal portion  143  precedes front face  115  of airbag  110  such that the airbag does not tend to get between an out of position occupant  16  and instrument panel  12 . 
       FIGS. 4-13E  comprise a method for folding an inflatable airbag and deployment flap.  FIGS. 4-5  depict a top elevation view and a cross-sectional view of airbag assembly  110 , wherein airbag  110 , throat flap  120 , wrapper  130 , deployment flap  140 , housing  150 , and inflator  160  are placed in predetermined orientations for packaging. Assembly  100  may be packaged on a work table having a cutout, within which housing  150  may be placed. Airbag  110  may be oriented such that it is in a planar configuration, with front face  115  placed over housing  150 , and top face  116  and side faces  118  partially showing. Top face  116  is on the same side of housing  150  as window sidewall  152 . Throat flap  120 , wrapper  130 , and deployment flap  140  are on the same side of the housing as cabin sidewall  151 . In the depicted configuration, airbag  110  may be described as having an upper portion  126  and a lower portion  127 , wherein the upper portion is located on windshield side  152  of housing  150 , and lower portion  127  is on cabin side  151  of housing  150 . Throat-distal portion  143  and distal edge  144  of deployment flap  140  extend beyond airbag  110  on the cabin sidewall  151  side of housing  150 . 
       FIG. 5  depicts some features of airbag assembly  100  that are not readily appreciated in  FIG. 4 . The various sidewalls of housing  150  may form a void  154  into which airbag  110  may be placed via open side  153 , after the airbag has been packaged. Throat portion  111  is coupled to housing  150  via inflator  160 . Throat distal portion  123  of throat flap  120  is coupled to throat-proximal portions  131  and  141  of wrapper  130  and deployment flap  140  via stitching  105 . Distal portions  133  and  143  of wrapper  130  and  140  extend away from cabin side  151  of housing  150 . 
       FIG. 6  is a top elevation view of airbag assembly  100  after side portions  108  of airbag  110  have been folded inwardly, toward housing  150 , such that each side portion is folded about ⅓ of the width of airbag  110 . Bottom portion  126  may then be folded upwardly, toward housing  150 , such that airbag  110  is manipulated into the configuration depicted in  FIGS. 7-8 . 
       FIG. 7  is a top elevation view of airbag assembly  100  after bottom portion  126  has been folded upwardly such that the bottom portion no longer crosses cabin sidewall  151  of housing  150 , but rather crosses windshield sidewall  152 . A distal edge of bottom portion  126  is on the same side of housing  150  as upper portion  127 . 
       FIG. 8  is a cross-sectional view of the airbag assembly of  FIG. 7 , wherein airbag  110  is depicted after lower portion  126  has been folded upwardly toward upper portion  127 . When folded upwardly, lower portion  126  no longer crosses cabin sidewall  151  of housing  150 , but rather crosses windshield sidewall  152 . A next step for folding airbag  110  comprises forward-rolling upper portion  126  from distal edge  128  of the upper portion. 
       FIG. 9  is a cross-sectional view of the airbag assembly of  FIG. 8  after upper portion  126  has been forward-rolled. Upper portion  126  may be forward rolled by a first fold being formed at a predetermined distance from distal edge  128  of the upper portion, and the distal edge being directed toward housing  150  in a direction that is away from upper portion  127 . 
       FIG. 10  is a cross-sectional view of the airbag assembly  100  after forward rolled upper portion  126  has been placed within housing  150 . As described herein, housing  150  comprises a plurality of walls that form an interior void  154  that has an open top side  153 . After being forward rolled, upper portion  126  may be placed on top of throat portion  111  and inflator  160 . 
       FIG. 11  is a top elevation view that depicts a next step in a method for packaging airbag assembly  100 , wherein upper portion  127  is accordion-folded. Upper portion  127  may be folded at a predetermined distance from distal edge  128  in a direction that is away from open side  153  of housing  150 . Upper portion  127  may continue to be accordion-folded a predetermined number of times. Accordion-folds are formed by making consecutive folds in directions that vary by 180°. 
       FIG. 12  is a cross-sectional view of airbag assembly  100  after upper portion  127  has been accordion-folded and placed on top of forward-rolled lower portion  127  within void  154  of housing  150 . Accordion-folded upper portion  127  is oriented such that distal edge  128  is on the windshield sidewall  152  side of housing  150 . 
       FIGS. 13A-13F  depict a method for folding a deployment flap.  FIGS. 13A-13F  also depict a method for packaging a deployment flap. Deployment flap  140  may be packaged by accordion-folding and forward folding.  FIG. 13A  depicts a first accordion-fold  146  being formed in deployment flap  140  of airbag assembly  100 . First accordion fold  146  may be formed a predetermined distance D 1  from proximal edge  142  of deployment flap  140 , wherein the fold is made such that distal portion  143  is directed toward open side  153  of housing  150 . First accordion-fold  146  may be made a predetermined distance from stitching  105 , rather than distal edge  142 . First accordion-fold  146  is made such that wrapper  130  is not folded with deployment flap  140 . 
       FIG. 13B  is a cross-sectional view of airbag assembly  100  after a second accordion-fold  147  has been made in deployment flap  140 . Second accordion-fold  147  may be made a predetermined distance D 2  from first accordion-fold  146 . Second accordion fold  147  is made such that distal portion  143  is directed away from housing  150 . In other words, second accordion-fold  147  orients distal portion  143  in a position that is 180° opposite of the direction of first accordion-fold  146 . Distances D 1  and D 2  may be identical. 
       FIG. 13C  is a cross-sectional view of airbag assembly  100  after a third accordion-fold  148  has been made in deployment flap  140 . Third accordion-fold  148  may be made a predetermined distance D 3  from second accordion-fold  147 . Third accordion fold  148  is made such that distal portion  143  is directed toward housing  150 . In other words, third accordion-fold  148  orients distal portion  143  in a position that is 180° opposite of the direction of second accordion-fold  147 . Distances D 2  and D 3  may be identical. In the depicted embodiment, an entire length of deployment flap  140  is formed into accordion folds, such that a distance D 4  from third accordion fold to distal edge  144  is the same as distance D 3 . In other embodiments, the deployment flap may be folded more or fewer than 3 times, and the distances between folds may vary. 
       FIG. 13D  is a cross-sectional view of airbag assembly  100  after a forward fold  149  has been formed in accordion-folded deployment flap  140 . After deployment flap  140  has been accordion-folded, the flap may comprise first, second, and third accordion folds  146 ,  147 , and  148 . A next step in a method for folding the deployment flap may comprise forward-folding deployment flap  140  such that distal portion  143  and distal edge  144  are positioned between second and third accordion-folds  147  and  148 . In the depicted embodiment, forward-fold  149  is made in a direction that is towards open top side  153  of housing  150 , wherein the forward-fold comprises a distance D 5  that is about ½ the length of accordion-folded deployment flap  140 . Distances for D 1 -D 4  may each be from about 40 mm to about 200 mm. Distance D 5  may be from about 20 mm to about 100 mm. Assembly  100  may further comprise tack stitching  109 , which can extend through the wrapper and all folded layers of the deployment flap. Tack stitching  109  is configured to rupture or breakaway during inflatable airbag deployment. 
       FIG. 13E  is a top elevation view of a portion of inflatable airbag assembly  100  after deployment flap  140  has been placed in the packaged configuration and breakaway tack stitching  109  has been sewn through the deployment flap and wrapper  130 . Wrapper  130  may also comprise perforations  139 , which are configured to rupture during inflatable airbag deployment. As noted above, throat flap  120  is coupled to wrapper  130  and deployment flap  140  via stitching  105 . Tack stitching  109  is depicted as three discrete columns of stitching; however, assembly  100  may only have a center column of tack stitching or two outside columns of tack stitching, which may be called tack stitching on the lateral sides of the deployment flap. 
       FIG. 13F  is a cross sectional view depicting the packaged configuration of airbag  110 , throat flap  120 , wrapper  130 , and deployment flap  140 .  FIG. 13F  also illustrates a next step in a method for packaging airbag assembly  100 . After deployment flap  140  has been accordion-folded and forward-folded, it may be placed on top of accordion-folded upper portion  126  of airbag  110 . Wrapper  130  may then be wrapped around deployment flap  140  and airbag  110 , such that distal edge  134  of distal portion  133  is adjacent to windshield sidewall  152  of housing  150 . Distal portion  133  may then be coupled to windshield sidewall  152  such that deployment flap  140  and airbag  110  are retained in their packaged configurations. For clarity,  FIG. 13F  depicts airbag  110  and deployment flap  140  as extending beyond top portion  153  of housing  150 . One skilled in the art will recognize that in the packaged configuration, the airbag and/or deployment flap may not extend above the top of the airbag housing. Each column of tack stitching may extend from about 10 mm to about 60 mm. 
     Any methods disclosed herein comprise one or more steps or actions for performing the described method. The method steps and/or actions may be interchanged with one another. In other words, unless a specific order of steps or actions is required for proper operation of the embodiment, the order and/or use of specific steps and/or actions may be modified. 
     Reference throughout this specification to “an embodiment” or “the embodiment” means that a particular feature, structure or characteristic described in connection with that embodiment is included in at least one embodiment. Thus, the quoted phrases, or variations thereof, as recited throughout this specification are not necessarily all referring to the same embodiment. 
     Similarly, it should be appreciated that in the above description of embodiments, various features are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure. This method of disclosure, however, is not to be interpreted as reflecting an intention that any claim require more features than those expressly recited in that claim. Rather, as the following claims reflect, inventive aspects lie in a combination of fewer than all features of any single foregoing disclosed embodiment. Thus, the claims following this Detailed Description are hereby expressly incorporated into this Detailed Description, with each claim standing on its own as a separate embodiment. This disclosure includes all permutations of the independent claims with their dependent claims. 
     Recitation in the claims of the term “first” with respect to a feature or element does not necessarily imply the existence of a second or additional such feature or element. Elements recited in means-plus-function format are intended to be construed in accordance with 35 U.S.C. §112 ¶ 6. It will be apparent to those having skill in the art that changes may be made to the details of the above-described embodiments without departing from the underlying principles of the invention. Embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows.