Abstract:
A method of manufacturing a vehicle frame, includes: forming compatible threads on a first rail composed of a first material and a second rail composed of a second material; forming a pair of locators on the first and second rails, said locators configured to indicate an alignment condition of the first rail and second rail when screwed together; and screwing together the first rail and second rail.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part and claims the benefit of U.S. patent application Ser. No. 13/221,142 titled “Vehicle Support Frames with Interlocking Features for Joining Members of Dissimilar Materials” filed Aug. 30, 2011, now U.S. Pat. No. 8,915,530, which is hereby incorporated by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to methods of manufacturing vehicle frame assemblies, particularly those frame assemblies incorporating threaded connections. 
     BACKGROUND 
     Conventional vehicle support frames can be composed of different materials including, for example, steel, aluminum and reinforced polymer composites. Vehicle manufacturers attempt to strike a balance between weight reduction and structural rigidity. It is desirable to design lightweight vehicle frames for full-sized trucks. Aluminum structural members can be designed to achieve up to a 50% weight reduction while still meeting performance targets. Joining aluminum members to steel frame rails presents challenges. 
     For example, MIG welding aluminum cross members to steel rails is a challenging task as the weld-compatibility between most steels and aluminum is low. Welding, however, provides a cost-effective and robust manner of joining vehicle assembly structural members. Accordingly, it is desirable to consider manufacturing techniques that employ alternative joining techniques. 
     Past joining techniques have considered incorporating threaded connections between vehicle frame components. For example, in World Intellectual Property Organization Publication No. WO 96/39322 titled “Method for Joining Structural Components” screw attachments of two cross rails is discussed. Such threaded connections between structural components is, however, generally less desirable than welded connections. 
     Therefore, it still is desirable to have techniques for applying welds in vehicle frame assemblies that incorporate the use of threaded connections. Additionally, it is also desirable to improve upon existing threaded connection designs for vehicle structural members. 
     SUMMARY 
     The present disclosure addresses one or more of the above-mentioned issues. Other features and/or advantages will become apparent from the description which follows. 
     One advantage of the present disclosure is that it provides teachings on manufacturing vehicle frame assemblies using threaded connections with welded connections. Moreover, a locating system is provided to ensure proper alignment of components having compatible threads. Additionally, the use of adhesives and adhesive wells are discussed herein, thereby providing additional structural rigidity to vehicle components. 
     One exemplary embodiment of the present disclosure relates to a method of manufacturing a vehicle frame that includes: forming compatible threads on a first rail composed of a first material and a second rail composed of a second material; forming a pair of locators on the first and second rails, said locators configured to indicate an alignment condition of the first rail and second rail when screwed together; and screwing together the first rail and second rail. 
     Another exemplary embodiment of the present disclosure relates to a method of manufacturing a vehicle frame, including: forming compatible threads on an interconnecting member (ICM) and a first rail composed of a first material; screwing together the ICM and first rail; and welding the ICM to a second rail composed of a second material. 
     Another exemplary embodiment of the present disclosure relates to a vehicle frame assembly, including: a first vehicle structural member composed of a first material; a second vehicle structural member composed of a second material; compatible threads on the first and second vehicle structural members; and locators on the first and second vehicle structural members, said locators configured to indicate an alignment condition of the first and second vehicle structural members when screwed together. 
     Joining vehicle frame assembly rails composed of dissimilar materials using welding and adhesives will be explained in greater detail below by way of example with reference to the figures, in which the same reference numbers are used in the figures for identical or essentially identical elements. The above features and advantages and other features and advantages of the present teachings are readily apparent from the following detailed description of the best modes for carrying out the invention when taken in connection with the accompanying drawings. In the figures: 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded perspective view of an exemplary vehicle frame assembly, according to the present disclosure. 
         FIG. 2  is a side view of the vehicle frame assembly of  FIG. 1 . 
         FIG. 3  is a side view of a bolt from the vehicle frame assembly of  FIG. 1  at circle  3 . 
         FIG. 4  is an exploded perspective view of another exemplary vehicle frame assembly, according to the present disclosure. 
         FIG. 5  is an exploded perspective view of another exemplary vehicle frame assembly, according to the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to the drawings, wherein like characters represent examples of the same or corresponding parts throughout the several views, there are shown various vehicle frame assemblies for use in motor vehicle chassis. Frame assemblies include structural components interconnected through threaded connections. In the illustrated examples, the threaded connections are coupled or mixed with adhesive or welded connections. Locators are also included on components to assist with alignment of threaded components. Thus, improved vehicle frame structures and manufacturing techniques for the same are provided with the present disclosure. 
     The teachings herein are applicable to any type of frame, especially vehicle frames including frames for pickup trucks, vans, minivans, sports utility vehicles, sedans, coupes, commercial vehicles, and all utility vehicles. 
     Referring now to  FIGS. 1-3 , there is shown an exemplary vehicle frame assembly  10  according to an embodiment the present disclosure. Vehicle frame assembly  10  is taken from a cross rail assembly for a vehicle, e.g., a spare tire frame. As shown in  FIG. 1 , assembly  10  includes two vehicle structural components  20 ,  30  configured to screw into another vehicle structural component  40 , specifically a cross rail. Vehicle structural components  20 ,  30  can be intermediate/interconnecting members between the cross rail  40  and another structural component (e.g., a side rail) or vehicle structural components can be an extension of rail  40 . In the illustrated embodiment, components  20 ,  30  are a continuation of rail  40 . Components  20  and  30  are composed of steel. Cross rail  40  is composed of aluminum in this embodiment. Other material selections and combinations will be appreciated including non-metals and composites. 
     Components  20 ,  30  are shown disconnected from cross rail  40 , in  FIG. 1 . Component  20  includes a threaded key  50 . Cross rail  40  includes a receptor  60  that is threaded with compatible threads to key threads. Both components include an orifice  70 ,  80  on the component  20  and cross rail  40 , respectively that acts as an alignment locator. When key  50  of component  20  is fully inserted into receptor  60  of cross rail  40  orifices  70  and  80  align. In another process a bolt  90  is inserted into each orifice  70 ,  80  to ensure that the alignment stays. Orifices  70 ,  80  are threaded with compatible threads  100  to the threads  110  on bolt, such as  90 . 
     In the illustrated embodiment components  20 ,  30  and  40  are shown as rectangular rails. Other vehicle structural components and/or rail configurations can be used, such as cylindrical rails or, as previously stated, interconnecting members. 
     At an opposing end of cross rail  40  another threaded component  30  is attachable to the rail via threads, as shown in  FIG. 1 . Component  30  includes a threaded key  120 . Cross rail  40  includes another receptor  130  that is threaded with compatible threads to key  120 . Both components include an orifice  140  on component  30  and orifice  150  on cross rail  40 , respectively that acts as an alignment locator. When key  120  of component  30  is fully inserted into receptor  130  of cross rail  40  orifices align. In another process, a bolt  90  is inserted into each orifice  140 ,  150 . Orifices  140 ,  150  are threaded with compatible threads (e.g.,  100 ) to the threads  110  on bolt  90 , as shown in  FIG. 3 . Orifices  140 ,  150  are anti-rotation features—or locators—that can be applied for part handling or field usage. 
     Threads in the receptors  60  and  130  on end of cross rail  40  can be the same or different size. Thread size can be altered to be larger or smaller than the threads illustrated herewith. Threads provide additional resistance preventing relative movement between the components  20 ,  30  and cross rail  40 . 
     To assemble cross rail  40  with components  20 ,  30  members are joined together by turning an end of component  20  or  30  and moving through the threads. The key  50  or  120  of components  20 ,  30  can be configured with a feature that enables turning, such as a textured surface for added grip, so that keys can be turned by manually. In another embodiment, a tool is designed to fit inside components  20 ,  30  to turn components into solid connection with cross rail  40 . 
     As illustrated in  FIG. 2 , one cross-sectional area of component  20 , x 1 , is smaller than another cross-sectional area of component, x 2 . The change in cross-sectional area forms a stop  160  on an outer surface of component  20 . Mechanical stop  160  is configured to distribute a clamp load on the component  20  to the outer surface of cross rail  40 . Stop  160  can be larger or smaller in other embodiments. In another embodiment, a stop is also formed on the internal surface of cross rail. 
     Component  20  key  50  is covered with an adhesive material  170 , as shown in the side view of the vehicle frame assembly of  FIG. 2 . Adhesive  170  is distributed on an outer surface of key  50 . Adhesive  170  is also accumulated in wells  180  of the threads formed on key  50 , as shown. The threads provide an area for structural adhesive to be applied. Adhesive  170  can be applied to one side or both sides of key  50  and cross rail receptor  60 . The structural adhesive  170  is a primary source of bonding and threads are a secondary source of bonding in this embodiment. Roles can be reversed or equilaterally distributed in other arrangements. 
     Referring again to  FIG. 3 , there is shown therein a side view of the bolt  90  from the vehicle frame assembly  10  of  FIG. 1 . Bolt  90  is twice threaded on a shaft of the bolt  90 . Threads  110  are formed to be compatible with threads  100  on locators  70 ,  80 ,  140 ,  150  of components  20 ,  30  and cross rail  40 . Another orifice (not shown) is added internally to the keys  50 , and  120  of components  20 ,  30  to intermesh with threads  110  on bolt. A hexagonal head  190  is also on bolt  90  for compatibility with a crescent wrench or other tool. Adhesive  170  is applied to bolt threads in another embodiment. 
     Now with reference to  FIG. 4 , there is shown an exploded perspective view of another exemplary vehicle frame assembly  200 . Vehicle frame assembly  200  is taken from a cross rail assembly for a vehicle, e.g., a spare tire frame. As shown in  FIG. 4 , assembly  200  includes two vehicle structural components  210 ,  220  configured to screw into another vehicle structural component, specifically a side rail  230 . Vehicle structural component  220  is an extension of side rail  230 . Vehicle structural component  210  is an interconnecting member (or ICM) between a cross rail (such as cross rail  40  of  FIG. 1 ) and another structural component (e.g., side rail  230 ). Side rail  230  is composed of steel. ICM  210  is composed of steel in this embodiment as well. Component  220  is composed of aluminum. Other material selections and combinations will be appreciated including non-metals and composites. 
     Components  210 ,  220  are shown disconnected from side rail  230  in  FIG. 4 . Component  220  includes a threaded key  240 . Side rail  230  includes a receptor  250  that is threaded with compatible threads to key  240  threads. When key  240  of component  220  is fully inserted into receptor  250  of side rail  230  orifices  260 ,  270  align. In another process, a bolt  280  is inserted into each orifice  260 ,  270  to ensure that the alignment stays. Orifices  260 ,  270  are threaded with compatible threads to the threads on bolt  280 . 
     In the illustrated embodiment components are shown as rectangular rails. Other vehicle structural components and/or rail configurations can be used, such as cylindrical rails or, as previously stated, interconnecting members. 
     Intersecting side rail  230  is another threaded component  210  attachable to side rail via threads, as shown in  FIG. 4 . ICM  210  includes a threaded key  290 . Side rail  230  includes another receptor  300  that is threaded with compatible threads to key  290 . Both components include an orifice  310 ,  320  that acts as an alignment locator. When key  290  of component is fully inserted into receptor  300  of side rail  230 , orifices  310 ,  320  align. In another process, a bolt (such as  280 ) is inserted into each orifice  310 ,  320 . Orifices  310 ,  320  are threaded with compatible threads to the threads on bolt. Orifices are anti-rotation features—or locators—that can be applied for part handling or field usage. Both component  220  and ICM  210  include an orifice  260  and  310 , respectively that acts as an alignment locator. 
     Threads on side rail  230  can be of the same or different sizes. Thread size can be altered to be larger or smaller than the threads illustrated herewith. Threads provide additional resistance preventing relative movement between the components and cross rail. 
     To assemble cross rail with components, members are joined together by turning an end of components  210 ,  220  and moving through the threads. The keys  290 ,  240  of components  210 ,  220  can be configured with a feature that enable turning. In another embodiment, a tool is designed to fit inside components to turn components into solid connection with side rail  230 . Component keys  240 ,  290  can be covered with an adhesive material in other embodiments. 
       FIG. 5  is an exploded perspective view of another exemplary vehicle frame assembly  400 . Vehicle frame assembly  400  includes an interconnecting member  410  welded to a side rail  420  for the vehicle frame at one end and formed with a threaded key  430  at another end. In this embodiment, side rail  420  and ICM  410  are composed of steel. A cross rail  440  is configured with a receptor  450  that is compatible with threads on key  430 . Cross rail  440  is composed of aluminum. 
     Vehicle frame assembly  400  is taken from a cross rail assembly for a vehicle frame assembly. As shown in  FIG. 5 , assembly  400  includes a vehicle structural component (e.g., ICM  410 ) configured to screw into another vehicle structural component, specifically a cross rail  440 . In the illustrated embodiment, side rail  420  is composed of steel. ICM  410  is composed of steel in this embodiment as well and is welded onto side rail  420  at weld line  460 . A cross rail  440  is composed of aluminum. Other material selections and combinations will be appreciated including non-metals and composites. 
     Threads can be the same or different. Thread size can be altered to be larger or smaller size than the threads illustrated herewith. Threads provide additional resistance preventing relative movement between the component  410  and cross rail  440 . 
     Those familiar with the art to which this invention relates will recognize various alternative designs, combinations and embodiments for practicing the invention within the scope of the appended claims.