Abstract:
A front end module is described, wherein the module includes a plastic component connected to a metallic substrate. The metallic substrate can be formed by hydroforming and shaped into a substantially unitary member. The plastic component is then molded about the metallic substrate and simultaneously forms connections thereto at discrete locations along the length of the metallic substrate.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]    The instant application claims priority to U.S. Provisional Patent Application Serial No. 60/434,923, filed Dec. 19, 2002, the entire specification of which is expressly incorporated herein by reference. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The present invention generally relates to components comprised of metallic and plastic content, and more particularly to front end modules including a plastic material connected to a metallic substrate.  
         BACKGROUND OF THE INVENTION  
         [0003]    Currently, structural components for vehicles, such as vehicle front end modules and door supports are made of metal and/or plastic. Front end modules provide structure to the vehicle as well as providing attachment structure for various vehicle components, such as the headlamps, radiator, fan, horn, and the like. Preferably, the front end modules can be provided in a single unit assembly, which is ready to be mounted to the vehicle by the manufacturer.  
           [0004]    Commonly, such structural components are made from several stampings that are welded together. Alternatively, such components have been made from closed section metal, such as by extrusion or hydroforming. The use of closed section metal provides a relatively stronger component. Typically, however, additional metal material must be welded to the closed section metal components to provide for attachment surfaces.  
           [0005]    These structural components are not currently made entirely from plastic material for larger vehicles because of the inability to meet vehicle performance requirements. However, use of plastic components in conjunction with metal to provide attachment points for the vehicle components is known in the art. In some instances, the metal structural component is attached to the plastic component with mechanical fasteners, such as screws or rivets. But, the use of this method is relatively cost and labor intensive.  
           [0006]    Another method of securing the plastic to the metal structure is shown in U.S. Pat. No. 6,273,496 to Guyomard et al. and assigned to Valeo Thermique Moteur. This reference appears to disclose a front panel that includes metal structural components, including a closed section metal component. A plastic material is overmolded over the metal structure.  
           [0007]    Another method of securing plastic to metal is shown in U.S. Application Publication No. 2001/0053431 to Goldbach et al. in the name of Bayer Corporation. Another such plastic and metal part is shown in U.S. Pat. No. 5,190,803 to Goldbach and assigned to Bayer Akhengesellsschaft.  
           [0008]    Accordingly, there exists a desire for front end modules that include a plastic component attached to a metallic substrate, especially wherein the plastic component can be connected to the metal substrate during fabrication without the use of mechanical fasteners while also using a relatively small amount of plastic material to achieve the connection.  
         SUMMARY OF THE INVENTION  
         [0009]    In accordance with a first embodiment of the present invention, a front end module is provided, comprising a metallic component having at least one opening formed therein. The module further comprises a plastic component disposed about at least a portion of the metallic component, wherein a first portion of the plastic material extends through the at least one opening and a second portion of the plastic material extends about an external surface of the metallic component so as to connect the plastic component to the metallic component.  
           [0010]    In accordance with another embodiment of the present invention, a front end module is provided, comprising a contoured unitary metallic component having at least one opening formed therein. The module further comprises a plastic component disposed about at least a portion of the metallic component, wherein a first portion of the plastic material extends through the at least one opening and a second portion of the plastic material extends about and envelopes an external surface of the metallic component so as to connect the plastic component to the metallic component.  
           [0011]    In accordance with another embodiment of the present invention, a front end module is provided, comprising a contoured unitary metallic component having at least one opening formed therein, wherein the metallic component includes a horizontal portion and two spaced and opposed vertical portions extending therefrom. The module further comprises a plastic component disposed about at least a portion of the metallic component, wherein a first portion of the plastic material extends through the at least one opening and a second portion of the plastic material extends about and envelopes an external surface of the metallic component so as to connect the plastic component to the metallic component.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]    A further understanding of the present invention will be had in view of the description of the detailed description of the preferred embodiments, when viewed in conjunction with the accompanying drawings wherein:  
         [0013]    [0013]FIG. 1 is a front perspective view of a front end module, in accordance with the general teachings of the present invention; and  
         [0014]    [0014]FIG. 2 is a rear perspective view of the front end module depicted in FIG. 1, in accordance with the general teachings of the present invention. 
     
    
       [0015]    The same reference numerals refer to the same parts throughout the various Figures.  
       DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0016]    The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.  
         [0017]    For example, although the following description primarily describes the present invention in connection with a front end module, it is to be appreciated that the present invention is likewise applicable to all applications wherein it is desired to connect a plastic component to a metallic component without the need for separate fasteners.  
         [0018]    With reference to the Figures, a composite front end module in accordance with the general teachings of the present invention is generally shown at  10 .  
         [0019]    The front end module  10  is preferably comprised of a single (e.g., unitary) metallic member, such as, but not limited to, a tube generally indicated at  12  (which is preferably manufactured by hydroforming) that is preferably joined to a plastic component, such as but not limited to a panel generally indicated at  14 .  
         [0020]    Preferably, the tube  12  comprises a closed cross section. The use of such closed cross section metal components provides rigidity to the module  10 . The closed form section can take any suitable configuration. It need not necessarily have a constant cross sectional shape. Such structures are particularly useful for vehicle support structures. It will be understood that open cross-section metal components may also be used within the scope of the present invention. The tube  12  may comprise any suitable metal, such as but not limited to steel, aluminum, and the like.  
         [0021]    The tube  12  can be configured in any number of configurations. However, those configurations that are suitable for use in front end modules are preferred. By way of a non-limiting example, the tube  12  preferably begins at the upper area of the module and is adapted to be connected to a vehicle structure such as a fender (not shown). The tube  12  extends generally horizontally as shown over the area corresponding to the headlamp module area or mount  16 . The tube  12  then turns and runs generally vertically down roughly parallel with the area corresponding to the location of the side of the radiator (not shown). The tube  12  then turns to run generally horizontally and parallel with the area corresponding to the location of the bottom of the radiator (not shown). The tube  12  then turns to run generally vertically and upward roughly parallel with the opposite side of the area corresponding to the location of the radiator (not shown). The tube  12  then turns to run generally horizontally and over the opposing headlamp module area or mount  16  and ends at the opposite fender (not shown). As shown in FIGS. 1 and 2, the tube  12  generally comprises a u-shaped member with extensions  28  extending outwardly from each arm of the u-shaped member. Again, it is preferred that the tube  12  be formed as a one-piece closed cross-section member such as by hydroforming.  
         [0022]    The plastic panel  14  can be configured in a number of suitable configurations. However, those configurations that are suitable for use in front end modules are preferred. By way of a non-limiting example, the plastic panel  14  preferably comprises an upper cross member  18 , headlamp mount  16 , grill support  20 , hood latch mount  22 , vertical center support  24 , and the like. The plastic panel  14  may also comprise at least one, and more preferably a plurality of reinforcement members, e.g., strengthening ribs  26 . As shown, the plastic panel  14  is preferably contoured to allow for attachment of the aforementioned components, and the like, and also may be provided with additional surface effects, such as but not limited to openings, flanges, bosses, and other protuberances.  
         [0023]    The plastic panel  14  is preferably made from any suitable thermoplastic or thermoset material. One such example of a plastic material may comprise modified polyphenolene oxide. While one example of a suitable plastic is provided, it will be appreciated that any suitable thermoplastic or thermoset may be used within the scope of the present invention. Further, fillers or other additives may be added to the plastic material to strengthen the plastic panel  14 . Any suitable filler may be used. Such fillers may comprise, for example, glass fiber or plastic fiber.  
         [0024]    The extensions  28  of the front end module  10  are preferably fixed to the upper front end of the fenders through the ends  30  of the extensions  28  of the tube  12 . The ends  30  of the extensions  28  of the tube  12  can preferably include openings for receiving fasteners to secure the module  10  with the vehicle fenders. The lower portion of the tube  12  preferably joins to the vehicle chassis in two places through brackets (not shown) attached to the tube  12  at attached points  32 .  
         [0025]    The front end module  10  preferably locates the fenders and provides a structural load path from the fenders to the vehicle chassis. The front end module  10  also preferably locates and supports the loads created by the cooling module by way of integral mounting supports  34 . The front end module is also adapted to support a variety of other components such as, but not limited to an air filter housing, A/C receiver dryer, headlamp module, coolant reservoir, fan shroud, and horn which can also preferably be mounted to the front end module  10 . Mounting holes  36  can be provided to mount these components and the like.  
         [0026]    Tube  12  is preferably manufactured by first forming and piercing a tube, preferably by hydroforming. The tube  12  is then placed in an injection molding tool. The mold is then closed, wherein plastic material, preferably including reinforcement, such as glass fibers, is pumped into the cavity of the injection molding tool thus forming the panel  14  into the desired configuration and simultaneously joining it to the tube  12  at discrete locations generally indicated at  38  leaving the remainder of the tube&#39;s  12  front and back surface exposed. More specifically, in order to join the tube  12  to the panel  14 , an opening (not shown) is formed on one side of the tube  12 . An opposite opening  40  is formed on the opposite side of the tool. A core tool is inserted through the opening  40  and adjacent the opening on the opposite side of the tube  12 . The core tool provides a cavity that allows the plastic material to flow from one side of the tube  12  through the opening into the cavity of the core tool. In this manner, plastic flows through the opening, but does not fill the entire cavity of the tube  12 .  
         [0027]    Preferably, the plastic material forms a button-like structure  42  on the inside of the tube. This button-like structure  42  has edges that extend over the opening in the tube  12 . The plastic material forms on the opposite side of the tube  12  from the opening  40  and may include strengthening ribs  26 . With the connection in this manner, plastic is secured to the tube  12  without the need to fully fill the tube  12  with plastic material. Thus, the plastic material preferably infiltrates, at least partially, into the tube  12  at locations  38  and, after cooling, forms a connection point with the tube  12 . A connection securing the plastic panel  14  with the tube  12  is shown at  38  and is fully described in U.S. Patent Application Serial No. 60/398,901, by the same inventors hereto, and is incorporated herein by reference. It will be appreciated that the connections at the locations  38  can be configured in any number of forms, and can include, without limitation, depressions, openings, holes, apertures, bores, through bores, and the like.  
         [0028]    Further, as shown, the plastic material can preferably be formed around the tube  12 , as shown at  44 . Strengthening ribs  26  may also be included as set forth above. With connection made in this manner, the plastic material preferably forms around the outer surface of the tube  12  and, after cooling, forms a connection point with the tube  12 . Further, the connection made in this manner, by molding the plastic panel  14  to tube  12 , the need for separate fasteners to connect the plastic components of the metal substrate is eliminated. It will be appreciated, however, that separate fasteners may be included in addition to the connection system set forth above.  
         [0029]    While injection molding is the presently preferred method of making the module  10 , it will be appreciated that any other suitable forming technique may be uses within the scope of the present invention. These include, without limitation, compression molding, injection compression molding, extrusion compress, gas assist or water assist pressure molding, low pressure molding, blow molding, thermoforming and/or rotational molding.  
         [0030]    Those skilled in the art can now appreciate from the foregoing description that the broad teachings of the present invention can be implemented in a variety of forms. Therefore, while this invention has been described in connection with particular examples thereof, the true scope of the invention should not be so limited, since other modifications will become apparent to the skilled practitioner upon a study of the drawings, specification and appended claims.