Abstract:
An air flow control assembly for a motor vehicle is disclosed that includes an air dam component at the front of the vehicle, typically mounted to the front bumper, which extends substantially across the width of the bumper. It includes a rearwardly extending generally planar surface that is configured to underlie the interior space at the front of the vehicle as well as an engine compartment underpanel which is coupled to that air dam and underlies the vehicle engine compartment.

Description:
[0001]    This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/699,583, filed Sep.  11, 2012, the disclosure of which is hereby incorporated by reference in its entirety.    
     
    
     FIELD OF THE INVENTION 
       [0002]    The present disclosure generally relates to air flow control assemblies for motor vehicles and, more particularly, to air dams and engine compartment underpanels for motor vehicles. In this regard, an important aspect of this disclosure is directed to air dam and engine compartment underpanel assemblies for improving the aerodynamic characteristics of motor vehicles including, in particular, trucks and truck tractors. 
       BACKGROUND OF THE DISCLOSURE 
       [0003]    It is known that the aerodynamic characteristics of motor vehicles can be improved by an air dam which typically is mounted to the front of a motor vehicle and extends downwardly into proximity with the roadway. 
         [0004]    For example, U.S. Pat. No.  4 ,291,911 (Gallmeyer) describes an air dam apparatus which is particularly concerned with trucks and truck tractors. That air dam apparatus comprises a pivotally mounted flat doorlike panel which, when deployed into an operative position below the front bumper deflects air from the front to the sides of the vehicle. Correspondingly, U.S. Pat. No. 7,871,121 (Ragsdale) describes a flexible flat plastic panel which extends downwardly from the bumper of a truck, redirecting air flow around the sides of the wheels. 
         [0005]    Neither of these prior art air dams is capable of guiding air streams that impinge on the front of the vehicle in a manner which effectively reduces turbulence in both the engine compartment and interior areas forwardly thereof in the vehicle. 
         [0006]    This design inadequacy and other shortcomings of the prior art are successfully addressed by the novel air flow control assembly described herein. 
       SUMMARY OF THE INVENTION 
       [0007]    This disclosure is directed to an air flow control assembly for improving the aerodynamic characteristics of a motor vehicle by providing an air dam component at the front of the vehicle, typically mounted to the front bumper, which extends substantially across the entire width of the bumper and includes a rearwardly extending, generally planar surface that is configured to underlie the interior space at the front of the vehicle which is forward of the engine compartment, as well as an engine compartment underpanel component which is coupled to that air dam and underlies the vehicle engine compartment. These components of the assembly cooperate to route air flow when the vehicle is traveling at relatively high speeds so that it passes below the vehicle in a manner which effectively reduces turbulence and drag in both that interior space at the front end of the vehicle and in the engine compartment. As such, this air flow control assembly provides, among other things, enhanced fuel efficiency. 
         [0008]    In accordance with an important aspect of the present disclosure, the engine compartment underpanel component can be coupled to the air dam component mounted forwardly thereof by a plurality of fasteners such as, for example, plastic rivets which, optionally, can be of the type which are releasable and reusable for facilitating removal of the underpanel when service to the engine and other components in the engine compartment is desired and the engine compartment underpanel reattached thereafter. 
         [0009]    Another aspect of this disclosure concerns a tear-away feature for preventing damage to the air dam and/or engine compartment underpanel when either or both of them are contacted by a road obstacle. This feature is achieved by the use of fasteners which are designed to shear when a road obstacle is contacted by the air dam and/or engine compartment underpanel resulting in a force of predetermined magnitude is imparted to either of these components without significant, if any, damage thereto. 
         [0010]    It is to be understood that the foregoing general description and the following detailed description are exemplary and are provided for purposes of explanation only. Other features, benefits and objects of the air flow control assembly of this disclosure will be apparent to those skilled in this art from these descriptions. Accordingly, the invention is to be limited only by the scope of the appended claims. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0011]    In describing the features of the disclosed embodiment, reference is made to the accompanying drawing figures wherein like parts have like reference numerals and wherein: 
           [0012]      FIG. 1  is a front lower perspective view of the air dam and engine compartment underpanel of the present disclosure; 
           [0013]      FIG. 2  is a rear upper perspective view of the air flow control assembly shown in  FIG. 1 ; 
           [0014]      FIG. 3  is an exploded front perspective view separately showing the bumper, air dam and engine compartment underpanel, as well as the individual fasteners used to interconnect the same; 
           [0015]      FIG. 4  is a top plan view of the air dam component of the subject air flow control assembly; 
           [0016]      FIG. 5  is a front elevational view of the air dam shown in  FIG. 4 ; 
           [0017]      FIG. 6  is an upper rear perspective view of the air dam shown in  FIG. 4 ; 
           [0018]      FIG. 7  is a side elevational view of the air dam shown in  FIG. 4 ; 
           [0019]      FIG. 8  is a top plan view of the engine compartment underpanel of the air flow control assembly of this disclosure; 
           [0020]      FIG. 9  is a rear elevational view of the engine compartment underpanel shown in  FIG. 8 ; 
           [0021]      FIG. 10  is an upper rear perspective view of the engine compartment underpanel shown in  FIG. 8 ; 
           [0022]      FIG. 11  is a side elevational view of the engine compartment underpanel shown in  FIG. 8 ; 
           [0023]      FIG. 12  is a side elevational schematic view of an installed air flow control assembly of this disclosure; 
           [0024]      FIG. 13  is a bottom plan schematic view of an installed air flow control assembly of this disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0025]    Referring to the drawings, the reference numeral  20  generally designates an air flow control assembly of the present invention which includes an air dam component  21  and an engine compartment underpanel component  22 , which assembly, in the illustrated embodiment, is coupled to a bumper  23 . For example in the illustrated embodiment, bumper  23  includes a pair of tow hook holes  24 ,  25  and engine ventilation apertures  26 ,  27  and  28 . It will be appreciated that the present invention is not limited to any particular bumper design and construction. 
         [0026]    Air dam component  21  and engine compartment underpanel component  23  can be composed of a variety of materials including plastics, metal, fiberglass and composites, as well as other like materials known to those skilled in the art. It can be formed by injection molding, thermal forming, stamping or other manufacturing methods also known to those skilled in the art. 
         [0027]    As best shown in  FIGS. 1-7 , the air dam component  21  includes a front facing downwardly extending trim portion  29  which, at its lower end, extends into a curved portion  31  that, in turn, extends into a U-shaped rearwardly extending generally continuous planar surface  32  which is configured to underlie the interior space at the front end of the vehicle. Air dam component  21  can be secured to the bumper  23  by an inwardly extending peripheral mounting flange  33  at its upper edge which is configured to be attached to a mating inwardly extending mounting flange  23   a  on the lower portion of the bumper  23  by means of a plurality of fasteners  34  which are received in apertures  33   a  of air dam mounting flange  33  and correspondingly sized and spaced apertures  23   b  of bumper mounting flange  23   a.    
         [0028]    In the illustrated embodiment, the back portion of U-shaped planar portion  32  includes a raised mounting flange  35  which is configured to receive the forwardmost portion  36  of engine compartment underpanel component  22 . This permits the underpanel component to be received in flush relationship to the bottom surface of U-shaped planar portion  32  of air dam  21 . A plurality of fasteners  34  similar to those used in coupling the air dam  21  to the bumper  23  can be used to attach engine compartment underpanel component  22  to mounting flange  35  which extends through apertures  37  in mounting flange  35  and like-sized and spaced-apart apertures  37  in the forward end  36  of engine compartment underpanel component  22 . 
         [0029]    As shown in  FIGS. 1 ,  2  and  8 - 11 , engine compartment underpanel  22  can be provided with a generally flat perimeter portion  22   a  that extends rearwardly terminating in a downwardly curled lip  38 . A generally rectangular center portion  39  surrounds perimeter portion  22   a  and is downwardly tapered from the forward end to the rearward end. A plurality of longitudinal raised ribs  41  can be provided to add rigidity to the engine compartment underpanel component  22 . 
         [0030]      FIGS. 12 and 13  schematically illustrate the orientation of the air flow control assembly  20  of the present disclosure in a truck  42  having a hood  43  that encloses an engine compartment  44 , a front axle  45  and the front bumper  23  to which the trim portion  29  of air dam component  21  is coupled. Desirably, a top filler panel  46  on the topsurface of bumper  23  adjacent wheel well  47  can be provided to limit the flow of air into the wheel well. As shown in  FIGS. 12 and 13 , the back edge curl  38  of engine compartment underpanel component  22  preferably terminates slightly forwardly front axle  45  so as to avoid contact with the axle  45  when the vehicle is traveling along a roadway and the front end of the truck moves vertically as a result of contact by the tires  46  with irregularities in the roadway. 
         [0031]    Perimeter portion  22   a  of engine compartment underpanel component  22 , as shown in  FIG. 13 , includes inwardly tapered sides  22   b  which can accommodate angular movement of the tires  48  during right and left turns. In this regard, it will be appreciated that a common design for engine compartment underpanel  22  can be used with a variety of air dam component designs that are individually styled to accommodate the varied multiple truck platforms of different manufacturers. 
         [0032]    The road clearance between the air flow control assembly  20  of this disclosure designated by the fetters “RC” in  FIG. 12  should be as low as needed for the desired aerodynamic performance with sufficient clearance above the road to minimize possible damage to the air dam component and/or the engine compartment underpanel component by impact with obstacles. In this regard, there should be a minimum clearance of at least approximately six inches between the lowermost portion of the air dam component  21  and engine compartment underpanel component  22  with the ground. Generally, however, it is believed that a road clearance of approximately eight to eleven inches will be suitable for most installations. 
         [0033]    An important feature of this disclosure, concerns the ready removal of the engine compartment underpanel component  22  when access to the engine compartment is desired. This is facilitated by the use of fasteners such as, for example, plastic rivets which can be of a type which are releasable and reusable for facilitating removal of the underpanel when service to the engine and other components in the engine compartment is desired. These same rivets or replacements thereof can then be used for reattachment of that underpanel when such servicing of the engine compartment is completed. 
         [0034]    If desired, the fasteners  34  can be of a type which are designed to shear when a road obstacle is contacted by either the air dam component or engine compartment underpanel component contact a road obstacle, resulting in a force of predetermined magnitude being imparted to the particular component involved and enabling that component to separate from the assembly without significant, if any, damage to the particular assembly component involved. 
         [0035]    While the invention of this disclosure has been described in accordance with a preferred embodiment, it will be appreciated by those skilled in the art that modifications and/or changes may be made to the foregoing description without departing from the spirit and scope of this invention. Accordingly, the invention of this disclosure is not limited by this disclosure but rather by the scope of the appended claims.