Abstract:
This invention relates to an improved method for forming a full face fabricated vehicle wheel and includes the steps of: (a) providing a disc blank formed from a metal material; (b) subjecting the disc blank to a metal stamping operation to produce a partially formed non-bowl shaped full face wheel disc having at least one stamped pocket formed therein; (c) forming at least one decorative window in the partially formed full face wheel disc; (d) coining a back side of the window in the partially formed full face wheel disc; (e) trimming an outer edge of the partially formed full face wheel disc to a predetermined diameter; (f) forming a center hub hole in the partially formed full face wheel disc; (g) subjecting the partially formed full face wheel disc to one or more final metal forming operations to form at least one of an outer flange and a plurality of lug bolt mounting holes in the partially formed wheel disc so as to produce a finished full face wheel disc; and (h) securing the full face wheel disc to a preformed wheel rim to produce the finished full face fabricated vehicle wheel.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    This invention relates in general to vehicle wheels and in particular to an improved method for producing a full face fabricated vehicle wheel.  
           [0002]    A conventional fabricated vehicle wheel is typically of a two-piece construction and includes an inner disc and an outer “full” rim. The disc can be cast, forged, or fabricated from steel, aluminum, or other alloys, and includes an inner annular wheel mounting portion and an outer annular portion. The wheel mounting portion defines an inboard mounting surface and includes a center pilot or hub hole, and a plurality of lug receiving holes formed therethrough for mounting the wheel to an axle of the vehicle. The rim is fabricated from steel, aluminum, or other alloys, and includes an inboard tire bead seat retaining flange, an inboard tire bead seat, an axially extending well, an outboard tire bead seat, and an outboard tire bead seat retaining flange. In some instances, a three-piece wheel construction having a mounting cup secured to the disc is used. In both types of constructions, the outer annular portion of the disc is secured to the rim by welding.  
           [0003]    A full face fabricated vehicle wheel is distinguished from other types of fabricated wheels by having a one-piece wheel disc construction. In particular, the full face wheel includes a “full face” disc and a “partial” rim. The full face-disc can be formed cast, forged, or fabricated from steel, aluminum, or other alloys. The full face disc includes an inner annular wheel mounting portion and an outer annular portion which defines at least a portion of an outboard tire bead seat retaining flange of the wheel. The wheel mounting portion defines an inboard mounting surface and includes a center pilot or hub hole, and a plurality of lug receiving holes formed therethrough for mounting the wheel to an axle of the vehicle. The partial rim is fabricated from steel, aluminum, or other alloys, and includes an inboard tire bead seat retaining flange, an inboard tire bead seat, an axially extending well, and an outboard tire bead seat. In some instances, the outboard tire bead seat of the rim and the outer annular portion of the disc cooperate to form the outboard tire bead seat retaining flange of the full face wheel. In both types of constructions, the outboard tire bead seat of the rim is positioned adjacent the outer annular portion of the disc and a weld is applied to secure the rim and the disc together.  
         SUMMARY OF THE INVENTION  
         [0004]    This invention relates to an improved method for forming a full face fabricated vehicle wheel and includes the steps of: (a) providing a disc blank formed from a metal material; (b) subjecting the disc blank to a metal stamping operation to produce a partially formed non-bowl shaped full face wheel disc having at least one stamped pocket formed therein; (c) forming at least one decorative window in the partially formed full face wheel disc; (d) coining a back side of the window in the partially formed full face wheel disc; (e) trimming an outer edge of the partially formed full face wheel disc to a predetermined diameter; (f) forming a center hub hole in the partially formed full face wheel disc; (g) subjecting the partially formed full face wheel disc to one or more final metal forming operations to form at least one of an outer flange and a plurality of lug bolt mounting holes in the partially formed wheel disc so as to produce a finished full face wheel disc; and (h) securing the full face wheel disc to a preformed wheel rim to produce the finished full face fabricated vehicle wheel.  
           [0005]    Other advantages of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiment, when read in light of the accompanying drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]    [0006]FIG. 1 is a block diagram illustrating a prior art sequence of steps for producing a prior art full face fabricated vehicle wheel.  
         [0007]    [0007]FIG. 2 is a cross sectional view of a disc blank for use in producing the prior art full face fabricated vehicle wheel.  
         [0008]    [0008]FIG. 3 is a cross sectional view showing the initial stamping of the disc blank into a generally bowl shaped wheel disc.  
         [0009]    [0009]FIG. 4 is a cross sectional view showing the intermediate stamping of the bowl shaped disc to produce a partially formed wheel disc.  
         [0010]    [0010]FIG. 5 is a cross sectional view showing the forming of the windows in the partially formed wheel disc.  
         [0011]    [0011]FIG. 6 is a cross sectional view showing the trimming of the outer diameter of the partially formed wheel disc.  
         [0012]    [0012]FIG. 7 is a cross sectional view showing the forming of the hub hole and lug bolt mounting holes in the partially formed wheel disc.  
         [0013]    [0013]FIG. 8 is a cross sectional view showing the final stamping of the partially formed wheel disc to produce a finished prior art full face fabricated wheel disc.  
         [0014]    [0014]FIG. 9 is a sectional view of a prior art full face fabricated vehicle wheel.  
         [0015]    [0015]FIG. 10 is a block diagram illustrating a sequence of steps for producing a full face fabricated vehicle wheel in accordance with the present invention.  
         [0016]    [0016]FIG. 11 is a cross sectional view of a disc blank for use in producing the full face fabricated vehicle wheel in accordance with this invention.  
         [0017]    [0017]FIG. 12 is a cross sectional view showing the stamping of the disc blank into a partially formed wheel disc in accordance with this invention.  
         [0018]    [0018]FIG. 13 is a cross sectional view showing the forming of the windows in the partially formed wheel disc in accordance with this invention.  
         [0019]    [0019]FIG. 14 is a cross sectional view showing the coining of the windows in accordance with the present invention.  
         [0020]    [0020]FIG. 15 is a cross sectional view showing the trimming of the outer diameter and the forming of the center hub hole of the partially formed wheel disc in accordance with this invention.  
         [0021]    [0021]FIG. 16 is a cross sectional view showing the forming of the flange outer and inner diameters, the forming of the lug bolt mounting holes, and the forming of the fit up area to produce a finished full face fabricated wheel disc in accordance with this invention.  
         [0022]    [0022]FIG. 17 is a sectional view of a full face fabricated vehicle wheel in produced in accordance with this invention.  
         [0023]    [0023]FIG. 18 is a sectional view showing the tooling for performing the stamping of the disc blank into the partially formed wheel disc illustrated in FIG. 12 in accordance with the present invention.  
         [0024]    [0024]FIG. 19 is a sectional view similar to FIG. 12 showing the partially formed wheel disc after the stamping operation in accordance with the present invention.  
         [0025]    [0025]FIG. 20 is a view of the outwardly facing surface of the vehicle wheel produced in accordance with the sequence of steps of the present invention.  
         [0026]    [0026]FIG. 21 is a sectional view taken along line  21 - 21  of FIG. 20.  
         [0027]    [0027]FIG. 22 is a sectional view taken along line  22 - 22  of FIG. 20.  
         [0028]    [0028]FIG. 23 is a view of the outwardly facing surface of the prior art vehicle wheel produced in accordance with the prior art sequence of steps.  
         [0029]    [0029]FIG. 24 is a sectional view taken along line  24 - 24  of FIG. 23.  
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0030]    Referring now to the drawings, FIG. 1 illustrates a block diagram showing a prior art sequence of steps for producing a full face fabricated steel vehicle wheel, indicated generally at  60  in FIG. 9. Initially, in step  10 , a flat sheet of steel material (not shown) is formed into a disc blank  30 , shown in FIG. 2. The disc blank defines a generally uniform disc thickness T. Following this, the disc blank  30  is initially stamped in step  12  to produce a generally bowl shaped disc  32 , shown in FIG. 3. The bowl-shaped disc  32  includes an outer annular portion  34 , an inner annular wheel mounting portion  36  having a “flattened” bottom, and an intermediate portion  37  having a generally concave profile. In particular, during the initial stamping operation of step  12 , the disc blank  30  is stamped to define a first predetermined axial distance A 1  defined between an inner surface  34 A of the outer annular portion  34  and an inner surface  36 A of the inner mounting portion  36 . Alternatively, in step  12 , the disc blank  30  can be stamped to produce an intermediate portion  37  having a generally straight profile (not shown).  
         [0031]    The bowl-shaped disc  32  is then stamped into a partially formed disc  38  having a predetermined profile, shown in FIG. 4, during step  14 . Next, during step  16 , a plurality of windows  40  (only one window illustrated in FIG. 5) are formed in the disc  38  to produce a partially formed disc  42 . Following this, the windows  40  are coined and an outer edge of the partially formed disc  42  is trimmed to a predetermined diameter during step  18  to produce a partially formed disc  44  shown in FIG. 6. Next, in step  20 , a center hub hole  46  and a plurality of lug bolt mounting holes  48  (only one hole  48  is illustrated) are formed in the disc  44  to produce a partially formed disc  50  shown in FIG. 7. Following this, the partially formed disc  50  is restriked and then subjected to a final stamping operation during step  22  to produce a finished full face steel wheel disc  52  shown in FIG. 8. During step  22 , a second predetermined axial distance A 2  is defined between an inner surface  54 A of an outer annular portion  54  of the disc  50  and an inner surface  56 A of an inner mounting portion  56  of the disc  52 . In the illustrated embodiment, the second predetermined axial distance A 2  is less than the first predetermined axial distance A 1 . Alternatively, the second predetermined axial distance A 2  can be equal to the first predetermined axial distance A 1 . Following this, the full face disc  52  is secured to a partial steel wheel rim  59  during step  24  to produce the finished full face fabricated steel vehicle wheel  60  shown in FIG. 9.  
         [0032]    Thus, in a conventional prior art full face steel wheel disc application, the initial stamping operation of step  12  is operative to form a bowl-shaped disc  32  having a finished part “tread” depth (i.e., the axial distances A 1  and A 2  are the same) or to form a bowl-shaped disc  32  having a deeper tread depth (i.e., the second axial distance A 2  is greater than the first axial distance A 1 ). Also, in a conventional prior art steel full face wheel disc application the initial stamping operation of step  12  is operative to form a bowl-shaped disc  32  wherein the intermediate portion  37  has a generally concave bowl wall surface (as shown in FIG. 3), or alternatively, a generally straight bowl wall surface (not shown). A generally similar sequence of steps can be used to produce a prior art full face fabricated aluminum vehicle wheel (not shown) having a prior art full face fabricated aluminum wheel disc (not shown).  
         [0033]    Referring now to FIG. 10, there is illustrated a block diagram showing a sequence of steps for producing a full face fabricated vehicle wheel in accordance with the present invention. The full face fabricated vehicle wheel produced according to this sequence of steps is illustrated as being a full face fabricated steel or aluminum vehicle wheel, indicated generally at  78  in FIG. 17. However, it will be appreciated that the present invention can be used in conjunction with other types of fabricated steel or aluminum vehicle wheels having a full face fabricated steel or aluminum wheel disc. For example, the vehicle wheel can be a “modular wheel” construction including a “partial” rim and a full face wheel disc (such as shown in U.S. Pat. No. 5,360,261 to Archibald et al.), the disclosure of this patent incorporated herein by reference.  
         [0034]    Turning to FIG. 10, a preferred sequence of steps for producing the full face fabricated vehicle wheel  78  of the present invention will be discussed. Initially, in step  100 , a flat sheet of suitable metal material (not shown) is formed into a disc blank  130 , shown in FIG. 11, by a metal forming operation. Preferably, the disc blank is formed by a stamping or blanking operation during step  100 . The disc blank  130  defines a generally uniform disc thickness T 1 .  
         [0035]    Following this, the disc blank  130  is subjected to a metal forming operation in step  102  to produce a partially formed wheel disc  132 , shown in FIGS. 12, 18 and  19 , having fully formed stamped pockets. As shown therein, the partially formed wheel disc  132  includes an outer annular portion  134 , an inner annular wheel mounting portion  136  having a generally flattened bottom, and an intermediate portion  138  having finish formed pockets which are later subjected to a metal forming operation which is effective to produce a plurality of decorative windows in the wheel disc as will be discussed below. In particular, the metal forming operation of step  102  is a stamping operation whereby the disc blank  130  is engaged by a plurality of dies (seven of such dies  180 ,  182 ,  184 ,  186 ,  188 ,  190  and  192  being illustrated in FIG. 18), and a binder ring or draw pad  194 .  
         [0036]    During step  102 , the dies  180 - 192  are preferably operative to produce a partially formed wheel disc  132  having a first predetermined axial distance B 1  defined between an inner surface  134 A of the outer annular portion  134  and an inner surface  136 A of the inner annular portion  136 . As will be discussed below, by forming the partially formed disc  132  with the fully formed stamped pockets  138  directly from the flat blank  130  during step  102 , the initial stamping operation  12  associated with the forming of the prior art bowl-shaped disc  32  is eliminated and the use of the binder ring  194  during step  102  is effective to produce a wheel disc  132  without any of the “tooling marks” on the outboard face of the disc  132  which are present on an outboard face of the associated prior art wheel disc  52 . The term tooling marks as used herein refers to the visible marks on the outwardly facing surface of the full face wheel disc. This is shown by comparing the tooling marks, schematically indicated by dashed lines  52 A on the outwardly facing surface of the prior art wheel disc  52  of the prior art vehicle wheel  60  shown in prior art FIG. 23 and produced according the sequence of steps disclosed in prior art FIG. 1, to the “clean” (i.e., no visible tooling marks or virtually non-existent tooling marks) on the outwardly facing surface of the wheel disc  160  of the vehicle wheel  78  produced in accordance with the sequence of steps disclosed in FIG. 10 of the present invention. It is noted that lines  52 B shown on prior art FIG. 23 are shading lines for illustration purposes and are not tooling marks. Similarly, the lines  160 A shown on FIG. 20 are shading lines for illustration purposes.  
         [0037]    The binder ring  194  is needed for two purposes. First, due to the rather extreme depth of the pockets  138  (and the resulting windows  142  discussed below), the depth being illustrated in FIG. 19 by reference letter D, the binder ring  194  is effective to eliminate undulation or rippling of the material on the periphery of the disc  134  which is produced during step  102 . The depth D being greater than around one-half inch and more preferably, the depth D being around one inch. In the prior art wheel, the depth of the windows is generally less than one-half inch. Secondly, the binder ring  194  allowed the flat disc blank  130  to be directly processed by only using a single stamping operation in step  102  to produce a partially formed/fully stamped wheel disc  132 .  
         [0038]    Next, during step  104 , a plurality of decorative windows or openings  142  (only one of such windows  142  is illustrated in FIG. 13) are formed in the wheel disc  132  to produce a wheel disc  144 . In step  106 , the back side of the windows  142  are coined to produce a wheel disc  146 . Following this, an outer edge of the wheel disc  146  is trimmed to a predetermined diameter and a center hub hole  154  is formed in the disc  146  to produce a disc  148  during step  108 .  
         [0039]    In step  110 , the disc  148  is restriked, the disc  148  is subjected to a final stamping operation to form a flange  162 , and a plurality of lug bolt mounting holes  156  (only one hole  156  is illustrated in FIGS. 16 and 17) are formed in the disc  148  to produce a finished full face steel wheel disc  160  shown in FIGS. 16 and 17. The flange  162  of the disc  160  is operative to define an outboard tire bead seat retaining flange of the vehicle wheel  178 . During step  110 , a second predetermined axial distance B 2  defined between an inner surface  162 A of the flange  162  and the inner surface  136 A of the inner annular portion  136 . Preferably, the second axial distance B  1  and the first axial distance B 2  are approximately the same. Alternatively, the second axial distance B 2  can be different from the first axial distance B 1  if so desired.  
         [0040]    Following this, the full face wheel disc  160  is secured to a partial wheel rim, indicated generally at  170  in FIG. 17, by suitable means, such as for example by a weld  180 , to produce the finished full face fabricated steel vehicle wheel  78  shown in FIG. 17 of the present invention. The wheel rim  170  is preferably formed from the same material as the wheel disc  160 , and includes an inboard tire bead seat retaining flange  172 , an inboard tire bead seat  174 , a well,  176 , and an outboard tire bead seat  178 . Alternatively, the wheel disc  160  and/or the wheel rim  170  can be formed from different and/or other materials if so desired.  
         [0041]    One advantage of the present invention is that the partially formed/fully stamped wheel disc  132  is formed directly from the disc blank  130 . As discussed above, the prior art method included the initial stamping operation of step  12  of the disc blank  30  into a generally bowl-shaped disc  32 . Thus, the present invention eliminates a metal forming operation that was necessary in the prior art method. Also, the present invention produces a wheel disc  160  having none or virtually no tool marks on the outwardly facing surface thereof thereby producing a more cosmetically appealing vehicle wheel outwardly facing surface. The prior art wheel disc  52  included tool marks on the outwardly facing surface thereof of the wheel disc  52 .  
         [0042]    In accordance with the provisions of the patent statutes, the principle and mode of operation of this invention have been described and illustrated in its preferred embodiment. However, it must be understood that the invention may be practiced otherwise than as specifically explained and illustrated without departing from the scope or spirit of the attached claims.