Abstract:
An inflatable restraint module comprises an inflatable restraint canister including an inflatable restraint, an instrument panel including an inflatable restraint door, and a structural reinforcement member that maintains proper deployment of the inflatable restraint. The structural reinforcement member is attached to an inflatable restraint chute that extends from the instrument panel at a first location and is attached to the structural member and the instrument panel at a second location. Upon deployment of an inflatable restraint, the structural reinforcement member goes into tension, thereby causing the structural reinforcement member to relieve stresses imparted to the instrument panel. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Description:
TECHNICAL FIELD  
         [0001]    The present invention relates to an inflatable restraint module, and in particular to a structural reinforcement for an inflatable restraint module.  
         BACKGROUND OF THE INVENTION  
         [0002]    Typically, an inflatable restraint deploys rearwardly in a vehicle toward a passenger or occupant of the vehicle. The inflatable restraint, such as an airbag, may be located behind an instrument panel area, such as a dashboard. An inflatable restraint module may include an inflatable restraint canister that includes the inflatable restraint and an inflatable restraint chute. The dashboard may include an inflatable restraint door that is formed in the dashboard. Proper deployment of the inflatable restraint is necessary for the safety of the occupants of the vehicle. However, the inflatable restraint module and/or instrument panel may undergo mechanical failure or misalignment, such as a displacement of the dashboard, during the deployment of the inflatable restraint, thereby resulting in improper deployment of the inflatable restraint.  
           [0003]    Thus, a need exists for an improved inflatable restraint module that minimizes mechanical failure of the inflatable restraint module and/or instrument panel and maintains proper alignment of the inflatable restraint during deployment of the inflatable restraint.  
         SUMMARY OF THE INVENTION  
         [0004]    The inventors of the present invention have recognized these and other problems associated with conventional inflatable restraint modules. To this end, the inventors have developed a structural reinforcement member for an inflatable restraint module comprising a first attachment portion, an intermediate portion that extends from the first attachment portion, and a second attachment portion that extends from the intermediate portion. The first attachment portion of the structural reinforcement member is attached to an inflatable restraint chute that extends from an instrument panel. The second attachment portion of the structural reinforcement member is attached to a structural member and the instrument panel on an inboard surface of the instrument panel. Upon deployment of an inflatable restraint, the structural reinforcement member goes into tension, thereby causing the structural reinforcement member to relieve stresses imparted to the instrument panel.  
           [0005]    In another aspect of the invention, an inflatable restraint module comprises an inflatable restraint canister including an inflatable restraint, an instrument panel including an inflatable restraint door, and a structural reinforcement member attached at a first location to an inflatable restraint chute extending from the instrument panel and attached at a second location to the instrument panel. Upon deployment of the inflatable restraint, the structural reinforcement member goes into tension, thereby causing the structural reinforcement member to relieve stresses imparted to the instrument panel. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]    The present invention will now be described, by way of example, with reference to the accompanying drawings, in which:  
         [0007]    [0007]FIG. 1 is a perspective view of a structural reinforcement member for an inflatable restraint module according to an embodiment of the invention;  
         [0008]    [0008]FIG. 2 is a rear, inboard, cutaway perspective view of the inflatable restraint module when the structural reinforcement member is not attached to the inflatable restraint module;  
         [0009]    [0009]FIG. 3 is a rear, inboard, cutaway perspective view of the inflatable restraint module when the structural reinforcement member is attached to the inflatable restraint module; and  
         [0010]    [0010]FIG. 4 is a side view of the inflatable restraint module with an inflatable restraint and the structural reinforcement member when attached to the inflatable restraint module. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0011]    Referring to FIG. 1, a structural reinforcement member, shown generally at  10 , according to an embodiment of the invention, maintains proper deployment of an inflatable restraint about an inflatable restraint module  11  (FIGS.  2 - 4 ). The structural reinforcement member  10  may comprise any desirable material, such as steel, that may be stamped or formed using any desirable alternative method. The inventive feature and utility of the structural reinforcement member  10  is described in more detail below. Directions used in the description of the invention such as “rearward” and “vertical” are meant to establish a frame of reference in describing the invention and are not meant to restrict the or limit patentable features of the invention as described in the claims below.  
         [0012]    The structural reinforcement member  10  generally comprises a first attachment portion  12  and an intermediate portion  14  that extends from the first attachment portion  12  that is integral with a second attachment portion  16 . The first and second attachment portions  12 ,  16  include five fastener passages  18   a - 18   e  and a fastener passage  20 , respectively. However, the invention is not limited by the number of fastener passages and the first and second attachment portions  12 ,  16  may include any desirable amount of fastener passages.  
         [0013]    According to the illustrated embodiment, the structural reinforcement member  10  may also include a beveled portion  22  located at a neck  24  of the intermediate portion  14 . The purpose of the beveled portion  22  is to promote installation of the structural reinforcement member  10  about the inflatable restraint module  11 . However, the beveled portion  22  can be located at any desirable location of the structural reinforcement member  10 .  
         [0014]    The structural reinforcement member  10  may also include at least one stiffening rib  26  disposed on a surface  28  of the structural reinforcement member  10 . According to the illustrated embodiment, three stiffening ribs  26  in a “chicken foot” configuration are located on the surface  28 , which is hereinafter referenced as the outboard surface  28  of the first attachment portion  12  and the intermediate portion  14 . The stiffening ribs  26  may be offset or centrally located about a central portion of the intermediate portion  14 . The stiffening ribs  26  may be in any desirable form and may be of any desirable thickness. For example, the stiffening ribs  26  may be in the form of a groove or slot having a thickness that is greater than, equal to, or less than the thickness, T (FIG. 4), of the structural reinforcement member  10 . Alternatively, the stiffening ribs  26  may be solid so as to increase the thickness, T, of the intermediate portion  14  of the structural reinforcement member  10 . Although only three stiffening ribs  26  are illustrated on the surface  28  of the first attachment portion  12  and the intermediate portion  14  in a “chicken foot” configuration, any desirable amount or configuration of the stiffening ribs  26  may be disposed on any surface of the structural reinforcement member  10 . For example, the stiffening ribs  26  may be located on an inboard surface  30  (FIG. 4) of the structural reinforcement member  10 .  
         [0015]    The structural reinforcement member  10  may also include any desirable shape having any desirable width, W, length, L, thickness, T, or draft angle, θ. The width, W, length, L, and thickness, T, may be of any desirable dimension to impart greater stiffness about the inflatable restraint module  11 . Preferably, the width, W, length, L, and thickness, T, of the structural reinforcement member  10  may be increased in order to provide additional structure where there is an absence of an existing structure about the inflatable restraint module  11 , such as a radio mounting structure (not shown). The draft angle, θ, is referenced from a dashed line X, and a throat portion  32  (FIG. 1) of the intermediate portion  14  near the neck  24 . The dashed line, X, is generally parallel to the throat portion  32 . The draft angle, θ, generally defines the angle at which the intermediate portion  14  extends from the first attachment portion  12  in order to facilitate attachment of the structural reinforcement member  10  to the inflatable restraint module  11 .  
         [0016]    Referring now to FIGS. 2 and 3, the inflatable restraint module  11  comprises an inflatable restraint chute  34  and an instrument panel or dashboard  36  including an inflatable restraint door  38  (FIG. 4) that is laser etched or otherwise formed in the dashboard  36  by using any means well known in the art. As shown more clearly in FIG. 4, the dashboard  36  is affixed to a structural member  40   a , which is commonly referred to in the art as a “cross-car beam” or a “mag-beam” that may be located behind a firewall (not shown). More specifically, the dashboard  36  is indirectly attached to the structural member  40   a  through the intermediate attachment of the structural reinforcement member  10  at the second attachment portion  16 , as described in more detail below.  
         [0017]    As seen in FIG. 4, the dashboard  36  may include a soft, aesthetically pleasing skin material  42  that is visible to the occupants of the vehicle, and a rigid substrate  44  formed of any desirable thermoplastic resin, such as, for example, Acrylnitril-Butadien-Styrol-Copolymere (ABS), Polypropylene (PP), Polycarbonate-Acrylnitril-Butadien-Styrol-Copolymere (PC/ABS), Thermoplastic Olefin (TPO), or polyvinyl chloride (PVC). The dashboard may also comprise foam (not shown) between the skin material  42  and the rigid substrate  44 .  
         [0018]    The inflatable restraint chute  34  may be integral with and extend from the substrate  44 . Alternatively, the inflatable restraint chute  34  may be separate from and be attached to the substrate  44  with fasteners or a desirable adhesive. The inflatable restraint module  11  also includes an inflatable restraint canister  46 , which may be affixed to a structural member  40   b , that contains an inflatable restraint  48 , commonly referred to as an airbag. The inflatable restraint canister  46  and dashboard  36  may be directly or indirectly attached to the member  40   a , which may be a separate component or the same structural member as the structural member  40   b.    
         [0019]    Referring back to FIGS. 2 and 3, fasteners  50 , such as rivets, bolts, or the like, may pass through the fastener passages  18   a - 18   e  and  20  on the attachment portions  12 ,  16  and substrate fastener passages  52  on a dashboard inboard surface  54  and a chute surface  56 , respectively. The fastener  50  that passes through the fastener passage  20  also passes through the structural member  40   a , thereby anchoring and providing a hard connection from the substrate  44  and the second attachment portion  16  to the structural member  40   a . The fastener  50  that passes through the dashboard  36  at the second attachment portion  16  may be covered with an additional decorative closeout  51 , such as, for example, a valance panel. Although a total of six fastener passages  52  are disposed about the dashboard inboard surface  54  and the chute surface  56 , respectively, the number of substrate fastener passages  52  depend on the number of fastener passages  18   a - 18   e  and  20  formed in the attachment portions  12 ,  16 , respectively. Thus, the invention is not limited by the number of substrate fastener passages  52  included in the design of the structural reinforcement member  10  and inflatable restraint module  11 .  
         [0020]    Referring now to FIG. 4, the inflatable restraint  48  inflates and deploys through the inflatable restraint door  38  towards an occupant of the vehicle. Upon deployment of the inflatable restraint  48 , deployment forces, which are generally indicated by deployment geometry including a rearward vector, R, a vertical vector, V, and a thrust vector, D, occur about the inflatable restraint module  11 . The combination of the rearward vector, R, and the vertical vector, V, result in the thrust vector, D, and are each generally directed towards the occupant and the windshield, respectively. The thrust vector, D, may comprise any desirable angle, such as, for example, approximately 20 degrees, which is referenced from the rearward vector, R.  
         [0021]    Essentially, the deployment force occurring about the inflatable restraint module  11  when the inflatable restraint deploys imposes stresses on the inflatable restraint module  11 , particularly on the substrate  44  and the chute  34 , and attempts to cause rearward displacement of the inflatable restraint module  11 . Generally, the rearward vector, R, comprises most of the deployment force that attempts to cause rearward displacement of the chute  34  and the dashboard  36 . However, most of the deployment force associated with the rearward vector, R, is harnessed by the structural reinforcement member  10  due to the hard attachment of the structural reinforcement member  10  to the structural member  40   a , thereby causing the structural reinforcement member  10  to go into tension and relieving the stresses imposed on the substrate  44  and chute  34 .  
         [0022]    The structural reinforcement member  10  also retains head impact characteristics of the inflatable restraint module  11  under occupant loading of the inflatable restraint  48  such that the dashboard  36  and the structural reinforcement member  10  may bend or flex so that absorption of impact energy transmitted to the inflatable restraint  48  may be expedited about the inflatable restraint module  11  and the structural reinforcement member  10 . The thickness, T, of the structural reinforcement member  10  permits the retention of head impact characteristics through the inclusion of the bending and flexing qualities of the structural reinforcement member  10 . For example, in the illustrated embodiment, the structural reinforcement member  10  may be made of steel material having a thickness, T, of approximately 1.5 mm.  
         [0023]    The structural reinforcement member  10  may be implemented in the inflatable restraint module  11  having impact geometry including an inflatable restraint deployment angle, φ, which is referenced from a horizontal line, H, that is generally parallel from a vehicle floor or base pan (not shown). Accordingly, the structural reinforcement member  10  may be implemented in inflatable restraint modules  11  having inflatable restraint deployment angles, φ, that comprises a deployment force that urges rearward displacement of the chute  34  and dashboard  36  towards the rearward vector, R. The inflatable restraint deployment angle, φ, may comprise any desirable angle, such as, for example, approximately less than or equal to 30 degrees.  
         [0024]    Accordingly, the structural reinforcement member  10  provides additional structure to the inflatable restraint module  11  and restricts a deployment force that urges rearward displacement of the chute  34  and dashboard  36  at any distance, such as, for example, a distance approximately equal to 50 mm or more, thereby impeding resulting stresses of the substrate  44  that may otherwise displace or fracture a portion of the inflatable restraint module  11 , such as the dashboard  36  and/or chute  34 , causing improper deployment of the inflatable restraint  48 . Thus, the deployment geometry including vectors, R, V, and D, may be maintained in order to maintain proper alignment and deployment of the inflatable restraint  48 .  
         [0025]    Even further, in a head impact situation, the structural reinforcement member  10  may flex upon restricting a deployment force that urges rearward displacement of the chute  34  and dashboard  36 . Thus, the loading geometry including an inflatable restraint deployment angle, φ, may be maintained, thereby retaining head impact characteristics of the inflatable restraint module  11  under occupant loading of the inflatable restraint  48 .  
         [0026]    It should be understood that the aforementioned and other various alternatives to the embodiments of the invention described herein may be employed in practicing the invention. It is intended that the following claims define the scope of the invention and that the method and apparatus within the scope of these claims and their equivalents be covered thereby.