Abstract:
An air bag assembly including an inflator for discharging inflation gas and a gas receiving expansible air bag cushion of winged geometry disposed in fluid communication with the inflator such that upon release of inflation gas from the inflator the air bag cushion is deployed substantially over the windshield of an automobile as well as the pillars adjacent the windshield. View ports are present within the interior of the air bag cushion so as to maintain a degree of visibility for the vehicle operator after deployment has taken place. Mesh netting or a like material which does not unduly restrict visibility may extend across the internally formed view ports.

Description:
TECHNICAL FIELD 
     This invention relates to an air bag assembly for use in a vehicle, and more particularly to an air bag assembly including an inflatable air bag cushion deployable at the exterior of the vehicle windshield in covering relation to the windshield and surrounding frame. 
     BACKGROUND OF THE INVENTION 
     It is well known in the prior art to provide an air bag assembly including an inflatable air bag for protecting passengers seated within the interior of a vehicle. Such inflatable air bags may be deployable from a number of different locations at the interior of the vehicle including the steering column, the dash panel, the side doors, and the interior roof line. Such inflatable air bags may have a number of different configurations and inflation characteristics depending upon the location of deployment and desired function. By way of example, air bag cushions which are deployable from the steering column and dash panel are typically rapidly inflated and thereafter decompressed as the occupant to be protected comes into contact with the air bag cushion. Alternatively, it is known to utilize air bags of generally curtain-like configuration deployable from the interior roof line which may remain inflated for an extended period of time so as to provide a cushioning restraint during an extended roll-over event lasting for several seconds. 
     Air bag assemblies as are known in the prior art typically include a gas generating inflator which is stored in fluid communication with the inflatable air bag cushion. Upon sensing certain predetermined vehicle conditions, such as a certain amount of vehicle deceleration, a sensor sends a signal to the inflator thereby triggering the discharge of inflation gas into the air bag cushion. As the inflation gas enters the air bag cushion, the air bag cushion is forced into a deployed position for protection of the occupants within the interior of the vehicle. 
     While the deployment of air bag cushions within the interior of the vehicle may provide benefit to the occupants of the vehicle, such systems provide no benefit to persons on the exterior of the vehicle. By way of example, in the event of a collision between a standard automobile and a motorcycle or pedestrian, it is known that interaction may take place between the exterior surfaces of the automobile and such pedestrian or motorcycle operator which interactions are not subject to cushioning by the air bag cushions deployed at the interior of the vehicle. 
     SUMMARY OF THE INVENTION 
     The present invention offers advantages and alternatives over the prior art by providing an air bag assembly which is deployable substantially over the windshield of an automobile including the frame surrounding the windshield so as to provide a cushion for persons outside the vehicle who may come into contact with such vehicle portions during a collision event. 
     Advantageously, the present invention provides the feature of a substantially complete wrap-around configuration to cover the frame surrounding the windshield. 
     Advantageously, the present invention provides the further feature of integral viewing ports within the cushion structure thereby permitting the operator of the automobile to maintain visibility with the exterior environment subsequent to the deployment of the air bag cushion over the windshield. 
     These advantages and features are accomplished in a potentially preferred form of the invention by providing an air bag assembly for use in a vehicle outside of the passenger compartment. The air bag assembly includes an inflator for discharging inflation gas and a gas receiving expansible air bag cushion disposed in fluid communication with the inflator such that upon release of inflation gas from the inflator, the air bag cushion is deployed substantially over the windshield of the automobile as well as the frame surrounding the windshield. View ports are formed within the interior of the air bag cushion so as to maintain a degree of visibility for the vehicle operator after deployment has taken place. Mesh netting or a like material which does not unduly restrict visibility may extend across the internally formed view ports to promote dimensional stability of the deployed air bag cushion. The air bag cushion may be of a substantially tapered thickness from its base to its upper boundary surface thereby further promoting the proper orientation of the air bag cushion in covering relation to the windshield and surrounding frame. The materials forming the air bag cushion are preferably of an extremely low gas permeability and preferably comprise a textile material including a permeability blocking coating of suitable character. Thus, this invention provides a system for cushioning the impact of a person external to the occupant compartment of an automotive vehicle which advantageously substantially covers the windshield and surrounding frame of the automotive vehicle. In addition, the air bag cushion permits the operator of the vehicle to see through the cushion upon deployment thereby permitting the operator to engage in continued operation of the vehicle in an appropriate manner. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention is described below by way of example only, with reference to the accompanying drawings in which: 
     FIG. 1 is a perspective view of an automotive vehicle as may incorporate the air bag assembly according to the present invention; 
     FIG. 2 is a view similar to FIG. 1 wherein the air bag assembly according to the present invention is in a deployed state; 
     FIGS. 3A and 3B are cut away side views of the air bag assembly according to the present invention taken generally along line  3 — 3  in FIG. 1 illustrating potentially preferred orientations for attachment; 
     FIG. 4 illustrates a fully assembled air bag cushion for use in the air bag assembly according to the present invention; and 
     FIGS. 5A-5D illustrate the component parts of the air bag cushion as illustrated in FIG.  4 . 
    
    
     While the invention has been illustrated and generally described above and will hereinafter be described in connection with certain potentially preferred embodiments, it is to be understood that in no event is the invention to be limited to such illustrated and described embodiments. On the contrary, it is intended that the present invention shall extend to all embodiments including alternatives and modifications as may embrace the principles of this invention within the true spirit and scope thereof. 
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings wherein to the extent possible like reference numerals are used to designate like components throughout the various views, in FIG. 1 there is illustrated a vehicle  10  including a passenger compartment  12  for housing one or more vehicle occupants (not shown). The vehicle  10  further includes an outwardly projecting hood portion  14  which extends forward from a position generally adjacent a windshield  16 . Disposed below the hood portion  14  in the region adjacent to the windshield  16  is an air bag module  20  as will be discussed further hereinafter. 
     As will be understood, the windshield  16  is preferably formed of substantially clear glass or other suitable material and extends in a broad expanse in front of the passenger compartment  12  so as to afford the operator of the vehicle and other occupants a view of the region in front of the vehicle  10 . In order to secure the windshield  16  in place, it is mounted within a frame including side pillars  22  which are commonly referred to in the art as the “A” pillars of the vehicle which provide substantial structural support to the windshield  16  as well as to the passenger compartment  12 . The side pillars  22  are generally formed of metal and are substantially rigid in character. As will be appreciated, in the event that a person external to the vehicle  10  comes into contact with such side pillars  22  during a collision event, the side pillars will tend to resist energy absorptive deformation due to their substantially rigid stable character. Thus, while the windshield  16  will tend to absorb energy through flexure or breakage during an impact event, thereby providing a degree of cushioning to a person who may impact the windshield, such cushioning is generally unavailable in the event that impact occurs in relation to a side pillar  22 . 
     Referring now to FIGS. 2,  3 A-B,  4  and  5 A-D the present invention provides an inflatable air bag cushion  30  deployable in substantially covering relation to the windshield  16  and side pillars  22 . As shown, the air bag cushion  30  is preferably deployable outwardly from the air bag module  20  from a position adjacent the lower edge of the windshield  16 . As best illustrated in FIGS. 3A and 3B, it is contemplated that the air bag module  20  will preferably include a generally cylindrical gas generating inflator  32  which is inserted through one end wall of a generally trough shaped housing  34  of metal or plastic in a manner as will be well known to those of skill in the art. The air bag cushion  30  is preferably stored in folded relation over the gas generating inflator  32  in fluid communication therewith such that upon expulsion of gas by the inflator  32 , the air bag cushion  30  receives such gas and is deployed outwardly in the manner as illustrated in broken lines in FIGS. 3A and 3B. It is contemplated that the path of travel of the air bag cushion  30  upwardly across the windshield  16  may be directed by guidewires carried within a track extending along the edge of the side pillars  22 . While direct fluid communication between the air bag cushion  30  and the inflator  32  may be preferred, it is likewise contemplated that the inflating gas may be transferred from the inflator  32  to the air bag cushion  30  by means of appropriate tubing or other suitable transfer devices. 
     It is contemplated that the air bag module  20  may be stored at a number of different locations although attachment to the hood  14  in the region adjacent to the windshield  16  as illustrated in  3 A or attachment directly below the windshield  16  as illustrated in FIG. 3B may be preferred. Such attachment may be effected by any appropriate fixture including, by way of example only, one or more bolts or snap-fit elements  36  which extend between the housing  34  and the desired point of attachment. It is believed that the deployment of the air bag cushion  30  from regions underlying the hood  14  may provide the added benefit of causing forced outward articulation of the hood  14  during exit of the air bag cushion  30 . It is contemplated that such outward articulation may give rise to regions of raised profile across the hood  14  which can absorb energy by collapsing back into place upon impact by an external mass thereby providing a cushioning function during such an impact event. 
     The utilization of a passenger side air bag inflator  32  for inflation of the air bag cushion  30  is believed to be potentially beneficial in view of the relatively large volume of the air bag cushion  30  which may be in the range of about 60 liters or greater and will preferably be in the range of about 90 liters to about 140 liters. However, it is also contemplated that a multiplicity of gas generating inflators which expel smaller quantities of gas may be utilized if desired. 
     Referring now to FIG. 4, the air bag cushion  30  according to the present invention is preferably of a generally 3-dimensional expanded profile such that upon expansion, it assumes a substantially molded configuration over the windshield  16  and side pillars  22 . This potentially preferred configuration may be achieved by seaming together a relatively small number of material panels as illustrated in FIGS. 5A-5D. As illustrated, the air bag cushion  30  preferably includes a generally centrally located windshield cover section  40  and inwardly curving wing segments  42  extending in angled relation away from the windshield cover section  40 . As shown, the air bag cushion  30  preferably includes a base segment  44  which extends adjacent the lower edge of the windshield  16  and an upper boundary surface  46  which extends over the upper edge of the windshield  16 . As illustrated, it is contemplated that the thickness of the air bag cushion  30  will be greater at the base segment  44  than at the upper boundary surface  46 . It is believed that such reduction in thickness may facilitate the ability of the air bag cushion  30  to expand over the windshield  16 . As shown, the air bag cushion  30  also preferably includes an apron  48  of material extending away from the base segment  44  thereby establishing a transition between the air bag module  20  and the location of deployment of the air bag cushion  30 . As illustrated, a mouth opening  50  may be formed within the apron segment  48  to convey inflation gas from the gas generating inflator  32  into the expansible body of the air bag cushion  30 . 
     According to the illustrated and potentially preferred embodiment, the air bag cushion  30  also includes one or more view ports  56  disposed across the interior in overlying relation to the windshield  16 . As best illustrated in FIG. 2, such view ports  56  permit the operator of the vehicle  10  to maintain visibility with the exterior environment even after deployment of the air bag cushion  30  takes place. It is contemplated that such maintenance of visibility may permit the operator to continue to maneuver the vehicle in an appropriate manner. 
     According to a potentially preferred practice for forming the air bag cushion  30  of the present invention, a plurality of panels of appropriate material may be joined together by appropriate seaming operations. In particular, it is contemplated that the air bag cushion  30  including windshield cover section  40  and wing segments  42  may be formed from a relatively small number of discrete panels of material which are joined together in a complementary relationship. According to one potentially preferred construction practice, the air bag cushion  30  may be formed from a front panel  60  of one piece construction which forms the forward facing impact surface of the air bag cushion and a rear panel  70  of one piece construction which forms the surface of the air bag cushion adjacent to the windshield  16  during deployment. According to a potentially preferred arrangement, an upper edge panel section  80  forming the upper boundary surface  46  may extend between the upper edges of the front panel  60  and the rear panel  70 . A lower edge panel section  90  forming the base segment  44  may likewise extend between the front panel  60  and rear panel  70  at the lower edges thereof. While the utilization of single piece panels may be potentially preferred, it is likewise contemplated that panels formed from a plurality of individual pieces may also be utilized. 
     As illustrated in FIG. 5A, the front panel  60  preferably includes a substantially straight upper boundary edge  61  and a substantially straight lower boundary edge  62 . On either side of the upper boundary edge  61  and the lower boundary edge  62 , lateral wing segments  63 ,  64  extend slightly upwardly in an angled relationship. Disposed at the interior of the front panel  60  are one or more openings  66  within the panel material corresponding to the view ports  56  in the completed air bag cushion  30 . The openings  66  may be spanned by a layer of open weave mesh  67  or other suitable material of substantial see-through character. 
     As shown in FIG. 5B, the rear panel  70  is preferably of a substantially complimentary geometry to that of the front panel  60 . In particular, the rear panel  70  preferably includes an upper boundary edge  71  and upwardly angled lateral wing segments  73 ,  74 . The rear panel  70  also preferably includes one or more openings  76  of complimentary geometry to the opening  66  in the front panel  60 . An open weave mesh  77  or other suitable see-through material may extend across the opening  76 . As illustrated, the rear panel  70  also preferably includes a distending tail portion  78  which may be used in formation of the apron segment  48  and mouth opening  50  as shown in FIG.  4 . 
     The front panel  60  and the rear panel  70  are preferably seamed directly to one another along their lateral side edges as well as in the region surrounding the complementary openings  66 ,  76 . According to the potentially preferred practice, an upper edge panel section  80  as illustrated in  5 C extends in joining relation between the front panel  60  and the rear panel  70  at the upper edges thereof. Thus, as shown the upper edge panel section  80  preferably includes a substantially straight profile center section  81  which may be joined along its edges to the upper boundary edges  61 ,  71  of the front panel  60  and rear panel  70  respectively. In addition, the upper edge panel section  80  preferably includes wing segments  83 ,  84  extending in angled relation away from the center section  81  for connection along the upper edges of the lateral wing segments  63 ,  64  of the front panel  60  and the upper edges of the lateral wing segments  73 ,  74  of the rear panel  70 . 
     The front panel  60  and the rear panel  70  are further preferably joined at the bottom by use of the lower edge panel  90  as illustrated in FIG.  5 D. The lower edge panel  90  preferably includes a substantially straight edge segment  92  which may be joined to the lower boundary edge  62  of the front panel  60 . The lower edge panel  90  also preferably includes angled wing segments  93 ,  94  which may be joined to the corresponding lower boundary edges of the lateral wing segments  63 ,  64  and  73 ,  74  of the front panel  60  and rear panel  70  respectively. According to the illustrated and potentially preferred embodiment, the lower edge panel  90  preferably includes a flap portion  98  which may be joined about its edges to the distending tail portion  78  of the rear panel  70  so as to form the apron segment  48  of the air bag cushion  30  as shown in FIG.  4 . As illustrated, the seaming relation between the flap portion  98  and the distending tail portion  78  is such that a channel  52  is established terminating at the mouth opening  50  such that inflation gas may be communicated into the air bag cushion  30 . 
     Each of the panels  60 ,  70 ,  80 ,  90  forming the air bag cushion  30  is preferably formed from a substantially flat piece of material such as woven fabric or the like. Woven fabrics of nylon or polyester may be particularly preferred. If desired, such material may include a gas permeability blocking coating of a suitable composition. By way of example only, it is contemplated that such coatings may include compositions of silicone, urethanes, acrylics, polyamide dispersions or mixtures thereof. 
     While the geometry of the panels will permit the achievement of the generally desired configuration, it is contemplated that the achievement of the desired configuration as described above may be furthered enhanced by the inclusion of tethering elements which extend across the interior of the air bag cushion  30  between the front panel  60  and the rear panel  70 . Thus, it is contemplated that the front panel  60  may include a number of tethered connection points  69  at defined locations across the interior surface thereof and that the rear panel  70  will likewise include a series of complimentary connecting points  79  which extend at defined locations across the interior surface thereof. It is contemplated that the tethering elements may be in the form of straps or may be in form of direct connections between the front panel  60  and rear panel  70  thereby giving rise to a generally quilted like inflation profile. 
     It is contemplated that the panels  60 ,  70 ,  80 ,  90  may be joined together by any suitable method yielding a substantially stable connection suitable for maintenance of inflation gas within the cushion  30 . By way of example only, and not limitation, such methods may include industrial sewing, RF welding, ultrasonic welding, adhesive bonding, or combinations thereof. 
     It is contemplated that the size of the panel sections will be such that upon deployment, the windshield cover section  40  will extend substantially over the entire expanse between the bottom and the top of the windshield  16 . Moreover, it is contemplated that the wing segments  42  will extend in a substantially wrap-around relationship so as to substantially cover the side pillars  22  extending on either side of the windshield  16 . Furthermore, it is contemplated that both the placement and nature of the view ports  56  will be of such a nature that the operator of the vehicle will be able to maintain a degree of visibility upon deployment of the air bag cushion  30  so as to have the ability to continue maneuver the vehicle as may be desired. 
     It is to be understood that while the present invention has been illustrated and described in relation to certain potentially preferred embodiments, constructions, and procedures, that such embodiments, constructions and procedures are illustrative only and that the present invention is in no event to be limited thereto. Rather, it is contemplated that modifications and variations embodying the principles of the present invention will no doubt occur to those of skill in the art. It is therefore contemplated and intended that the present invention shall extend to all such modifications and variations as may incorporate the broad aspects of the present invention within the full spirit and scope of the appended claims and all equivalents thereto.