Abstract:
An occupant protection apparatus for protecting a front seat passenger of a vehicle. The apparatus includes an airbag module configured to be mounted in a instrument panel of a vehicle in front of the front seat passenger. The module includes an airbag and a gas generator. The airbag includes left and right inflatable lobes separated by a central gap. Each of the inflatable lobes is bounded by an outer panel forming an outer surface of the lobe and an inner panel forming an inner surface of the lobe.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application claims the benefit of and priority to U.S. Provisional Patent Application Nos. 61/064,285 and 61/006,784 filed Feb. 26, 2008 and Jan. 31, 2008, respectively. The foregoing provisional applications are incorporated by reference herein in their entireties. 
     
    
     BACKGROUND 
       [0002]    The present application relates generally to the field of airbag use in automotive vehicles. More specifically, the application relates to the use of an improved bi-lobular or twin lobe airbag geometry to simplify its manufacturability and reduce cost without compromising its ability to mitigate or eliminate occupant injury during a dynamic impact event. 
         [0003]    A twin lobe airbag utilizing a crescent shaped or C-shaped geometry for use on the lateral inboard panels is shown and described in U.S. Pat. No. 7,243,947 filed May 25, 2005, the entire disclosure of which is incorporated herein for reference. This crescent shaped geometry disclosed in the patent presents challenges in manufacturing. It should be noted that the airbag disclosed herein may be assembled and arranged in substantially the same manner as the airbag disclosed in U.S. Pat. No. 7,243,947 with the exception of the shape and geometry of the panels, which is different for the airbag of the present application as described further below. 
         [0004]    It would be advantageous for an airbag design to provide the safety benefits of a twin lobe design with an improved panel geometry and design which would be more efficient in terms of material usage and required processing (e.g. sewing, material handling), thereby reducing cost and the frequency of quality issues. 
       SUMMARY 
       [0005]    According to an exemplary disclosed embodiment an occupant protection apparatus is provided. The apparatus includes an airbag having left and right inflatable lobes separated by a central gap. Each of the inflatable lobes is bounded by an outer panel forming an outer surface of the lobe and an inner panel forming an inner surface of the lobe. The inner panels face each other and define the sides of central gap, and each of the inner panels is D-shaped. According to an alternative embodiment each of the inner panels may be oblong-shaped. 
         [0006]    According to an alternative disclosed embodiment an occupant protection apparatus is provided. The apparatus includes an airbag having left and right inflatable lobes separated by a central gap. Each of the inflatable lobes is bounded by an outer panel forming an outer surface of the lobe and an inner panel forming an inner surface of the lobe. The inner panels face each other and define the sides of central gap. The airbag includes an internal lateral tether extending across one of the left and right inflatable lobes between the inner and outer panels. Additionally, or alternatively, the airbag may include a substantially vertical tether positioned in the airbag between the gap and a gas generator for filling the airbag. 
         [0007]    It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only, and are not restrictive of the invention as claimed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    These and other features, aspects, and advantages of the present invention will become apparent from the following description, appended claims, and the accompanying exemplary embodiments shown in the drawings, which are briefly described below. 
           [0009]      FIG. 1  is a side view of an exemplary embodiment of a vehicle illustrating deployment of an exemplary embodiment of an airbag. 
           [0010]      FIG. 2  is a perspective view of an exemplary embodiment of a deployed airbag. 
           [0011]      FIG. 3  is a bottom view of an exemplary embodiment of a deployed airbag. 
           [0012]      FIG. 4  is a side view of the first generally D-shaped lateral inboard panel, used for constructing an exemplary embodiment of an airbag. 
           [0013]      FIG. 5  is a side view of the second generally D-shaped lateral inboard panel, used for constructing an exemplary embodiment of an airbag. 
           [0014]      FIG. 6  is a side view of the first generally oblong-shaped lateral inboard panel, used for constructing an alternative embodiment of an airbag. 
           [0015]      FIG. 7  is a side view of the second generally oblong-shaped lateral inboard panel, used for constructing an alternative embodiment of an airbag. 
           [0016]      FIG. 8  is a side view of an exemplary embodiment of a deployed airbag. 
           [0017]      FIG. 9  is a front view of an exemplary embodiment of a deployed airbag. 
           [0018]      FIG. 10  is a side view of an alternative embodiment of a deployed airbag. 
           [0019]      FIG. 11  is a front view of an alternative embodiment of a deployed airbag. 
           [0020]      FIG. 12  is a front view of an alternative embodiment of a deployed airbag. 
           [0021]      FIG. 13  is a front view of an alternative embodiment of a deployed airbag. 
       
    
    
     DETAILED DESCRIPTION 
       [0022]    One exemplary embodiment of an airbag incorporates the coupling of multiple lateral inboard panels, multiple lateral outboard panels, and one or more central panels to form a bi-lobular shaped inflated airbag. The panels may be individual pieces or a combination of multiple components joined by processing (e.g. sewing, bonding, welding) made of known airbag fabric material (e.g. nylon, polyester weave) which may be coated by some other material, (e.g. silicone rubber, polyolefin) which may be useful in containing inflating gases inside the airbag. The bi-lobular designed cushion, when inflated, mitigates occupant injury during dynamic impact, by distributing impact forces across the ribs and shoulders of the occupant rather than concentrating them on the sternum. Additionally, a concave region in the lower section of the cushion, and formed from the gap between the two lobes of the cushion also reduces loads exerted onto the head and neck of an out of position occupant. The airbag is in fluid communication with a gas generator. When initiated by a signal from a crash sensor, which responds to the deceleration resulting from a deployable vehicle crash event, the gas generator generates gas. The gas then flows into the folded cushion which inflates and expands, rupturing the airbag cover and allowing the cushion to extend and inflate into the vehicle interior in between the instrument panel and the occupant and providing protection to the occupant. 
         [0023]    Within the exemplary embodiment of an airbag, the geometry of the lateral inboard panels may be configured in a D-shape manner. This creates a concave region in between the lower lobe sections of the cushion. This concave region reduces the forces exerted on a small out of position occupant, while preserving beneficial energy absorption to naturally seated occupants during a dynamic impact event. Additionally, this D-shaped configuration provides manufacturing advantages over previous art. For example, this D-shaped configuration of the lateral inboard panels uses less material, which reduces the length of stitching required (which in turn reduces cost to manufacture and time to manufacture), reduces the manufacturing footprint required (i.e. smaller panel means smaller processing area required), and reduces the size of the manufacturing equipment required (e.g. sewing machine). To accommodate the lateral inboard panel geometry change and still provide the central gap used to mitigate potential injury to an out of position occupant during deployment, the central panel has been modified to contain an extension on both sides of one end of the panel. 
         [0024]    An exemplary embodiment of an airbag may incorporate the coupling of multiple lateral inboard panels, multiple lateral outboard panels, one or more central panels, and one or more tethers to form a bi-lobular shaped inflated airbag. This exemplary embodiment utilizes the bi-lobular design when inflated and incorporates the use of tethers for additional support so that during inflation the airbag takes and maintains the proper shape. Tethers are extremely useful for restricting the volume of certain sections or locations of the airbag to aid proper deployment. Tethers are also useful on bi-lobular designs to help maintain the pocket or gap located between the lateral inboard panels during deployment, which mitigates injury to out of position occupants or smaller occupants, such as children. The tethers may be positioned on the airbag externally or internally, and may run from front to rear, bottom to top, cross car (i.e. side to side), or may be utilized in other useful positions and locations. 
         [0025]    An alternative embodiment of an airbag may include the geometry of the lateral inboard panels to be configured in an oblong-shaped manner. An alternative embodiment still produces an airbag with a bi-lobular design. An alternative embodiment may include one or more than one tether, to provide support during deployment and to maintain proper shape to mitigate damage to occupants during a dynamic crash event. 
         [0026]    Referring to  FIG. 1 , an exemplary embodiment of vehicle  10 , comprising, gas generator  11 , occupant  13 , seat system  15 , vehicle dash board  17 , and airbag  20  is illustrated. Airbag  20  is illustrated in an inflated condition. Gas generator  11  produces the gas that inflates air bag  20  during deployment in the event of a dynamic impact of vehicle  10 . 
         [0027]    Referring to  FIG. 2 , a perspective view of an exemplary embodiment of airbag  20  is illustrated in an inflated condition. Airbag  20  comprises, central gap  23 , central panel  25 , second airbag cushion portion  31  (or right inflatable lobe  31 ), and first airbag cushion portion  41  (or left inflatable lobe  41 ). An exemplary embodiment of airbag  20  is constructed to position central gap  25  between first airbag cushion portion  41  and second airbag cushion portion  31 , to allow occupant  13  to fill central gap  25  during deployment of airbag  20 . 
         [0028]    Also referring to  FIG. 2 , second airbag cushion  31  comprises, second lateral inboard panel  33 , second lateral outboard panel  35 , remaining edge of second lateral inboard panel  37 , and remaining edge of second lateral outboard panel  39 . Second airbag cushion  31  may be constructed such that remaining edge of second lateral inboard panel  37  is coupled to remaining edge of second lateral outboard panel  39 , joining second lateral inboard panel  33  to second lateral outboard panel  35 . First airbag cushion  41  comprises, first lateral inboard panel  43 , first lateral outboard panel  45 , remaining edge of first lateral inboard panel  47 , and remaining edge of first lateral outboard panel  49 . First airbag cushion  41  may be constructed such that remaining edge of first lateral inboard panel  47  is coupled to remaining edge of first lateral outboard panel  49 , joining first lateral inboard panel  43  to first lateral outboard panel  45 . Central panel  25  may be coupled to both first airbag cushion  41  and second airbag cushion  31 . Second lateral inboard panel  33  is coupled to first lateral inboard panel  43 . The term “coupled” can mean either a joining of separate pieces by a separate operation, or portions of a continuous piece of airbag material, by a manufacturing process (e.g. sewing, bonding, or welding). 
         [0029]    Referring to  FIG. 3 , a bottom view of an exemplary embodiment of airbag  20  is illustrated in an inflated condition. First lateral inboard panel  43  is coupled to both first lateral outboard panel  45  and central panel  25 , forming first airbag cushion  41 . Second lateral inboard panel  33  is coupled to both first lateral outboard panel  35  and central panel  25 , forming second airbag cushion  31 . Additionally, second lateral inboard panel  33  is coupled to first lateral inboard panel  43 . Together, first airbag cushion  41  and second airbag cushion  31 , create the twin-lobular or bi-lobular design of airbag  20 . 
         [0030]    Referring to  FIG. 4 , a side view of an exemplary embodiment of second lateral inboard panel  33 . An exemplary geometry of second lateral inboard panel  33  is D-shaped and includes remaining edge of second lateral inboard panel  37  for joining second lateral inboard panel  33  to second lateral outboard panel  35 , central panel  25 , and first lateral inboard panel  43 . 
         [0031]    Referring to  FIG. 5 , a side view of an exemplary embodiment of first lateral inboard panel  43 . An exemplary geometry of first lateral inboard panel  43  is D-shaped and includes remaining edge of first lateral inboard panel  47  for joining first lateral inboard panel  43  to first lateral outboard panel  45 , central panel  25 , and second lateral inboard panel  33 . 
         [0032]    Also referring to  FIGS. 4 and 5 , the D-shaped geometry of second lateral inboard panel  33  and first lateral inboard panel  43  create a concave region in between the lower section of first airbag cushion portion  41  and the lower section of second airbag cushion portion  31 . This concave region reduces the forces exerted on a small out of position occupant, while preserving beneficial energy absorption to naturally seated occupant  13  during a dynamic impact event. Additionally, this D-shaped configuration provides manufacturing advantages over previous art. For example, this D-shaped configuration of first lateral inboard panel  43  and second lateral inboard panel  33  uses less material, which reduces the length of stitching required, which in turn reduces cost to manufacture and time to manufacture, reduces the manufacturing footprint required (i.e. smaller panel means smaller processing area required), and reduces the size of the manufacturing equipment required (e.g. sewing machine). To accommodate the D-shape of both lateral inboard panels and still provide the central gap used to mitigate potential injury to an out of position occupant during deployment, the central panel may be modified to contain an extension on both sides of one end of the panel. 
         [0033]    Referring to  FIG. 6 , a side view of an alternative embodiment of second lateral inboard panel  63 . An exemplary geometry of second lateral inboard panel  63  is oblong-shaped and includes remaining edge of second lateral inboard panel  67  for joining second lateral inboard panel  63  to both second lateral outboard panel  351  and central panel  251 . 
         [0034]    Referring to  FIG. 7 , a side view of an alternative embodiment of first lateral inboard panel  73 . An exemplary geometry of first lateral inboard panel  73  is oblong-shaped and includes remaining edge of first lateral inboard panel  77  for joining first lateral inboard panel  73  to both first lateral outboard panel  451  and central panel  251 . 
         [0035]    Referring to  FIG. 8 , a side view of an exemplary embodiment of airbag  20  is illustrated in an inflated condition. An exemplary embodiment of airbag  20  is constructed using D-shaped geometry for both first lateral inboard panel  43  and second lateral inboard panel  33  and may include the use of vertical tether  81 , and may include the use of horizontal tether  82  in two locations. Vertical tether  81 , positioned between the base of the gap and the top of the airbag, provides additional support so that during inflation the base of the gap is restrained and airbag  20  takes and maintains the proper shape for improved deployment, especially in situations involving a rear facing infant seat (rfis) and an out of position occupant (oop). Horizontal tether  82  supports the lobe during inflation. Vertical tether  81  and horizontal tether  82  may provide support to aid proper deployment by restricting the volume of certain sections or locations of airbag  20 . A tether may also be used on bi-lobular designs to help maintain the pocket or gap, located between first lateral inboard panel  43  and second lateral inboard panel  33 , during deployment, which mitigates injury to out of position occupants or smaller occupants, such as children. An alternative embodiment of airbag  20  may be constructed with zero or more than zero tethers. An alternative embodiment of airbag  20  may be constructed with tethers being internal or external to airbag  20 . 
         [0036]    Referring to  FIG. 9 , a front view of an exemplary embodiment of airbag  20  is illustrated in an inflated condition. An exemplary embodiment of airbag  20  may include the use of vertical tether  81 , positioned in the airbag between the base of the gap and the top of the airbag. An exemplary airbag  20  may also include horizontal tether  82  in two locations, one positioned in right inflatable lobe  31  between inner panel  33  and outer panel  35 , the other positioned in left inflatable lobe  41  between inner panel  43  and outer panel  45 . An alternative embodiment of airbag  20  may be constructed with zero or more than zero tethers. An alternative embodiment of airbag  20  may be constructed with tethers being internal or external to airbag  20 . 
         [0037]    Referring to  FIG. 10 , a side view of an alternative embodiment of airbag  201  is illustrated in an inflated condition. An alternative embodiment of airbag  201  may be constructed using oblong-shaped geometry for both first lateral inboard panel  73  and second lateral inboard panel  63  and may include the use of vertical tether  811 , and may include the use of horizontal tether  812  in two locations. Vertical tether  811 , positioned between the base of the gap and the top of the airbag, provides additional support so that during inflation the base of the gap is restrained and airbag  201  takes and maintains the proper shape for improved deployment, especially in situations involving a rear facing infant seat (rfis) and an out of position occupant (oop). Horizontal tether  812  supports the lobe during inflation. Vertical tether  811  and horizontal tether  812  may provide support to aid proper deployment by restricting the volume of certain sections or locations of airbag  201 . An alternative embodiment of airbag  201  may be constructed with zero or more than zero tethers. An alternative embodiment of airbag  201  may be constructed with tethers being internal or external to airbag  201 . 
         [0038]    Referring to  FIG. 11 , a front view of an alternative embodiment of airbag  201  is illustrated in an inflated condition. An alternative embodiment of airbag  201  may comprise two lobes, first airbag cushion portion  411  and second airbag cushion portion  311 . Alternative airbag  201  may further comprise vertical tether  811 , positioned in airbag  201  between the base of the gap and the top of the airbag, and horizontal tether  812  in two locations, one positioned in right inflatable lobe  311  between inner panel  63  and outer panel  351 , the other positioned in left inflatable lobe  411  between inner panel  73  and outer panel  451 . First airbag cushion portion  411  includes an oblong-shaped first lateral inboard panel  73  coupled to first lateral outboard panel  451 . Second airbag cushion portion  311  includes an oblong-shaped second lateral inboard panel  63  coupled to second lateral outboard panel  351 . An alternative embodiment of airbag  201  may utilize additional tethers at one or more than locations and may be external or internal to airbag  201 . 
         [0039]    Referring to  FIG. 12 , a front view of an alternative embodiment of airbag  20  is illustrated in an inflated condition. An alternative embodiment of airbag  20  may include the use of vertical tether  81 , positioned in the airbag between the base of the gap and the top of the airbag. An alternative airbag  20  may also include horizontal tether  82 , positioned to run between the inside of outer panel  35  and the inside of outer panel  45  in a cross-car direction. 
         [0040]    Referring to  FIG. 13 , a front view of an alternative embodiment of airbag  201  is illustrated in an inflated condition. An alternative embodiment of airbag  201  may include the use of vertical tether  811 , positioned in the airbag between the base of the gap and the top of the airbag. An alternative airbag  201  may also include horizontal tether  812 , positioned to run between the inside of outer panel  351  and the inside of outer panel  451  in a cross-car direction. 
         [0041]    Given the disclosure of the present invention, one versed in the art would appreciate that there may be other embodiments and modifications within the scope and spirit of the invention. Accordingly, all modifications attainable by one versed in the art from the present disclosure within the scope and spirit of the present invention are to be included as further embodiments of the present invention.