Abstract:
A headliner and air bag assembly includes a headliner having a left and right side edges and a carrier assembly having left and right rails extending along the left and right side edges of the headliner, respectively. The carrier assembly also includes a cross-member connecting the left and right rails. The left and right rails support at least one air bag assembly, and the carrier assembly provides structural support for the headliner and for the air bag assembly to prevent bending of the headliner during installation.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is the National Stage of International Application No. PCT/US00/34097, filed Dec. 15, 2000. which claims the benefit of U.S. Provisional application Ser. No. 60/172,395, filed Dec. 17, 1999. 
    
    
     TECHNICAL FIELD 
     The present invention relates to a vehicle headliner assembly including a carrier assembly which supports at least one air curtain on the headliner and adds structural integrity to the headliner assembly. 
     BACKGROUND OF THE INVENTION 
     Modularity in vehicle components is important for auto manufacturers because it simplifies the auto assembly process, thereby reducing parts. Recently, automotive interior headliners have been made modular by providing a headliner subassembly which includes overhead consoles, electronics, light sources, air curtains, and air curtain deployment equipment mounted on the headliner. The headliner and these various components are installed as a single unit subassembly into a vehicle. 
     One problem with the modularity concept in headliners is that the attachment of various heavy components around the periphery of the headliner may cause flexing or bending of the headliner, which can make handling and assembly difficult. 
     DISCLOSURE OF INVENTION 
     The present invention overcomes the problem described above by providing a carrier assembly which is adhesively secured to the periphery of the headliner for supporting the air bag system and adding structural integrity to the headliner subassembly for installation in the vehicle. The air bag igniter is mounted to the rear of the headliner so that it need not be mounted behind an overhead console. 
     More specifically, the present invention provides a headliner and air bag assembly including a headliner having left and right side edges. A carrier assembly includes left and right rails extending along the left and right side edges of the headliner, respectively, and a cross-member connecting the left and right rails. The left and right rails support at least one air bag assembly, and the carrier assembly is configured to provide structural support for the headliner and for the air bag assembly. Preferably, the carrier assembly is adhesively secured to the periphery of the headliner. 
     Another aspect of the invention provides a method of assembling a vehicle headliner and air bag assembly including the steps of: a) providing a plastic carrier assembly including left and right rails and a cross-member; b) positioning inflatable air curtains within the left and right rails; c) positioning an igniter assembly in the cross-member for deploying the air curtains; and d) attaching the carrier assembly to a headliner having left and right side edges such that the left and right rails extend along the left and right side edges, and the cross-member connects the left and right rails to structurally support the weight of the headliner and air bag assembly during installation. 
     Accordingly, an object of the invention is to provide a modular headliner assembly including a carrier assembly which supports the weight of the headliner and of various heavy components attached around the periphery of the headliner, such as the air curtains and inflator assembly, to prevent flexing or bending of the headliner during installation. 
     The above object and other objects, features, and advantages of the present invention are readily apparent from the following detailed description of the best mode for carrying out the invention when taken in connection with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS 
     FIG. 1 shows a perspective view of a headliner and air bag assembly in accordance with the present invention; 
     FIG. 2 shows an exploded perspective view of the assembly of FIG. 1; 
     FIG. 3 shows a partial schematic cross-sectional view of the headliner and air bag assembly of FIG. 1 installed in a vehicle; 
     FIG. 4 shows a partial vertical cross-sectional view taken through the rear header of the headliner and air bag assembly of FIG. 1; 
     FIG. 5 shows a partial vertical cross-sectional view of the assembly of FIG. 1 attached to a vehicle, the section being taken through one of a plurality of Forrester fasteners in the assembly; 
     FIG. 6 shows a partial cross-sectional view of a rear header in accordance with the invention; and 
     FIG. 7 shows a partial vertical cross-sectional view of a side rail in accordance with the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIGS. 1 and 2 show a headliner and air bag assembly  10  in accordance with the present invention. The headliner and air bag assembly  10  includes a headliner  12 , which is typically a PET, or other thermoformable material. A plastic carrier  14  includes left and right rails  16 , 18 , and a rear header  20  which is attached, such as by sonic welding, between the left and right rails  16 , 18  to form the carrier  14 . 
     An igniter assembly  22 , which includes a canister and inflator, is secured to the rear header  20 , and polypropylene or canvas tubes  24 , 26  extend from the igniter assembly  22  for deploying the air curtains  28 , 30 . 
     The air curtains  28 , 30  are housed within the left and right rails  16 , 18 , along with EPP foam countermeasures  32 , 34  for head impact protection. The air curtains  28 , 30  are configured for deployment along the side windows of a vehicle. 
     Once the countermeasures  32 , 34  and air curtains  28 , 30  have been assembled into the left and right rails  16 , 18 , a layer of scrim could be placed over this carrier subassembly to assure that debris does not inadvertently fall into the air curtain area. 
     FIG. 3 shows a vertical cross-sectional view of the headliner and air bag assembly  10  secured to a vehicle roof structure  36 . As shown, the headliner  12  is secured to the carrier  18  by hot melt adhesives  38 , 40 . Preferably, the hot melt adhesives  38 , 40  comprise adhesive number HM7239 from Bostik Hot Melt Adhesives of Middleton, Mass. 
     As shown, a coat hook  42  includes a base  44  with a bolt  46  and Z-clip  48  which secure the carrier  18  to the headliner  12  to form a headliner subassembly which is installed into the vehicle simply by pushing the Z-clips  48  into the openings formed in the roof structure  36 . 
     As shown in FIG. 3, hot melt adhesive  50  also secures the countermeasure  34  to the carrier  18 . 
     In this manner, the coat hook  42  holds the portion of the headliner  12  shown in FIG. 3 to the carrier  18  for handling. The coat hook  42  is illustrative, and may be replaced by a grab handle or assist handle. For example, as shown in FIG. 2, apertures  52 , 54  are provided in the left rail  16  at a location in which a grab handle would be provided. The grab handle would be provided with a similar structure as the bolt  46  and Z-clip  48  shown in FIG. 3 for attachment to the headliner  12 . Of course, multiple coat hook and assist handle attachments could be used throughout the assembly to secure various portions of the rails  16 , 18  to the headliner  12  to provide structural integrity to the assembly  10 . 
     As shown in FIG. 2, Forrester fastener locations  56  indicate the presence of a Forrester fastener, shown in FIG.  4 . FIG. 4 shows a vertical cross-sectional view taken through the rear header  20 , and indicates one of several Forrester fasteners  58  which are secured about the periphery of the carrier  14 . Preferably, the Forrester fastener is a pump fastener from Forrester Fastener Company of Clinton Township, Mich. The adhesive in the fastener is preferably an ethyl cyanoacrylate, such as adhesive #1414 from Loctite Company of Rocky Hill, Conn. Also, each Forrester fastener  58  includes stand-offs  60 , 62  on opposing sides thereof for transferring forces from the headliner  12  to the fastener  58 . Forrester fasteners are configured with a plunger arrangement and include glue therein, such that when the plunger is depressed the glue is dispensed for attaching the carrier  20  to the roof structure  36 . When the operator pushes on a marked location  64  (a location marker such as a sticker would be placed on the headliner  12 ), the forces would be transferred through the stand-offs  60 , 62  to the Forrester fastener  58  so that attachment glue is dispensed to secure the carrier  20  to the roof structure  36 . These Forrester fasteners 58 would be positioned at each Forrester fastener location  56  illustrated in FIG. 2 for attachment to the roof structure  36  of the vehicle. 
     FIG. 5 shows a cross-sectional view taken through one of the Forrester fastener locations  56  in the right rail  18 . As shown in FIG. 5, stand-offs  60 , 62  are provided for transferring forces from the headliner  12  to the Forrester fastener  58 , as described above with reference to FIG. 4, for dispensing glue to attach the headliner to the vehicle roof. 
     Turning to FIG. 6, a vertical cross-sectional view is shown of the rear header  20 , and FIG. 7 shows a vertical cross-sectional view of a right rail  18 . These components are preferably ABS plastic materials. 
     A subassembly including the carrier  14  and the air bag assembly including the igniter assembly  22 , tubes  24 , 26 , and air curtains  28 , 30 , as well as the countermeasures  32 , 34  are attached to the headliner  12  in a nesting fixture with the hot melt adhesive  38 , 40 . 
     When the air curtains  28 , 30  deploy, the hot melt adhesive  40  tears away from the headliner  12  (such as by tearing a scrim backing off of the headliner  12 ),  50  that the peripheral edge  70  of the headliner  12 , shown in FIG. 3, displaces downward to provide clearance to enable deployment of the air curtains  28 , 30  along the vehicle side windows. 
     Also, by mounting the igniter assembly  22  in the rear of the headliner assembly, the need for housing the igniter assembly underneath the console is eliminated, thereby maximizing the usable space behind the overhead console. 
     While the best mode for carrying out the invention has been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention within the scope of the appended claims.