Method for fabricating a wheel cover

Information

  • Patent Grant
  • 6279230
  • Patent Number
    6,279,230
  • Date Filed
    Monday, June 14, 1999
    24 years ago
  • Date Issued
    Tuesday, August 28, 2001
    22 years ago
Abstract
A wheel cover is formed to include a wrap around the circumference of the wheel cover. The wrap is an aesthetic portion of the wheel cover and not a part of a mechanical lock. It is formed in the wheel cover by spinning the wheel cover about its central axis. When the wheel cover is spinning at an appropriate speed, at least one pair of rollers is moved toward the spinning wheel cover. Lock generating rollers provide a force which is directed radially outwardly while wrap generating rollers provide a force which is directed radially inwardly. This force is of such a magnitude that it forces the outer edge of the wheel cover to follow the contour of the rollers. When the wrap is completely formed, the rollers are removed from engagement with the wheel cover and the wheel cover is stopped from spinning. Once the wheel cover is removed from the fixture of the spinning machine, it proceeds with further manufacturing steps to complete the manufacturing thereof before it is mounted to a wheel.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The invention relates to a method for fabricating a wheel cover. More specifically, the invention relates to a method for fabricating a wheel cover by forming an outer diameter having a mechanical lock at the outer edge thereof.




2. Description of the Related Art




Wheel covers are used to inexpensively provide an enhanced appearance for a steel wheel. Some wheel covers add a chromed or colored surface to the steel wheel without the costly step of actually chroming or painting the steel wheel. Chroming the steel wheel is costly because a steel wheel requires a great deal of surface finishing before it can receive the chrome material. Other wheel covers simulate an aluminum wheel. Because steel and aluminum wheels are capable of being manufactured to be as aesthetically pleasing as wheel covers, the primary advantage of the use of a wheel cover is to provide an aesthetically pleasing wheel surface at a low cost.




Therefore, the method for manufacturing wheel covers having a minimal number of flaws while maintaining the cost advantages is desired. One such method is disclosed in U.S. Pat. No. 3,214,220, issued to Foster et al. on Oct. 26, 1965. This patent discloses a wheel cover which is secured to an outer rim of a wheel. The wheel cover has a curl at its outer edge. The curl is created by rolling a disc of material inwardly. This curl is then forced into a groove formed within the outer rim of the wheel. Rolling is the act of forcing the outer rim of a disc out of its plane using a device which is moving radially outwardly from the center of the disc. Therefore, when a wheel cover is rolled, a roller or similar mechanism is rolled over the disc radially outwardly and then over the edge of the disc forcing the disc or wheel cover to have its outer edge curled. A crimping tool may be used in place of the rollers. This method is not desired because it forces anomalies in the thicknesses, i.e., bumps, of the disc due to the malleability thereof. Further, several rollers are required to ensure the rolling of the wheel cover is uniform. If several rollers or crimping tools are not used, the cycle time for such a mechanism will increase resulting in a higher manufacturing cost.




Another method for manufacturing a wheel cover is disclosed in U.S. Pat. No. 4,094,550, issued to Toal et al. on Jun. 13, 1978. This patent discloses a method for forming a wheel cover on a wheel. This patent also discloses folding or rolling over the edge of the trim ring, or wheel cover, to clinch a second piece of the resulting wheel cover. This act of rolling over is similar to that disclosed in U.S. Pat. No. 3,214,220, discussed above. A series of circumferentially spaced indentations are provided on the folded over portion of the trim ring member so as to prevent relative rotation between the members or pieces of the wheel cover and for the purpose of reducing noise. This rolled over edge does not enhance the ability of the wheel cover to be secured to the wheel. It is merely a point at which a support is secured to the wheel cover.




SUMMARY OF THE INVENTION




A method is disclosed for fabricating a wheel cover to permanently attach the wheel cover to a wheel. The wheel includes an outer rim flange. The method includes the step of forming a disc from a sheet of metal. The disc defines an outboard surface and an inboard surface, an outer edge and a central axis perpendicular to the outboard and inboard surfaces. The method also includes the step of stamping the disc to bend the disc through three dimensions. The method further includes the step of spinning the disc about the central axis. Finally, the method includes the step of applying a force to the outer edge of the disc while the disc is spinning to force the outer edge to bend over the inboard surface to create a wrap to be received by the outer rim of the wheel.




One advantage associated with the invention is the ability to manufacture a wheel cover to be mechanically locked to a wheel at the outer rim thereof. Another advantage associated with the invention is the ability to produce wheel covers through a reduced cycle time. Yet another advantage associated with the invention is the ability to eliminate bumps and any other anomalies which may be created when manufacturing a mechanical lock at the outer edge of the wheel cover. Still another advantage associated with the invention is to reduce the number of die operations into a single operation. A further advantage is the reduction of costs in the manufacturing of the wheel cover. Due to the versatility of the method, the method is advantageously interchangeable providing a single machine capable of manufacturing several different designs of wheel covers.











BRIEF DESCRIPTION OF THE DRAWINGS




Other advantages of the invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:





FIG. 1

is a perspective view of a machine incorporating the inventive method to manufacture a wheel cover;





FIGS. 2A and 2B

are side views partially cut away of a formed wrap in a spinning machine incorporating the inventive method to form an outer diameter and a mechanical lock, respectively;





FIG. 3

is an enlarged side view partially cut away of the wrap of a wheel cover engaged with two rollers while forming the outer diameter;





FIG. 4

is an enlarged side view partially cut away of the mechanical lock of a wheel cover engaged with two rollers; and





FIG. 5

is a cross-sectional side view partially cut away of a wheel cover manufactured from the inventive method secured to a wheel.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)




Referring to the Figures, a wheel cover is generally indicated at


10


. The wheel cover


10


includes a disc


12


of material. In one embodiment, the material is a malleable metal which has been stamped into a three-dimensional object.




The wheel cover


10


includes an outboard surface


16


, an inboard surface


18


and an outer edge


20


extending therebetween. The outboard surface


16


is visible by someone when the wheel cover


10


is attached to a wheel


19


which is, in turn, attached to a wheel hub of a motor vehicle (neither shown).




The inboard surface


18


is the surface opposite the outboard surface


16


. The inboard surface


18


faces the wheel


19


once it is attached thereto. The inboard surface


18


is not visible once the wheel cover


10


is secured to the wheel


19


.




The outer edge


20


extends between the outboard


16


and inboard


18


surfaces. The outer edge


20


is formed in a manner such that it is capable of receiving an outer rim flange


21


of the wheel


19


. When the outer edge


20


of the wheel cover


10


is spun formed, discussed in greater detail subsequently, it has an orientation which is generally perpendicular to its orientation prior to the completion of the inventive method. When secured to a wheel


19


, the outer edge


20


is disposed adjacent an inboard surface


22


of the wheel


19


as is shown in U.S. Pat. No. 5,829,843 which is hereby incorporated by reference. A sealant


23


extends between an outboard surface


24


of the wheel


19


and the inboard surface


18


of the wheel cover


10


.




A spinning machine is generally indicated at


26


. The spinning machine


26


is used to form a lock


42


and a wrap


46


, both of which are discussed subsequently, adjacent to and at the outer edge


20


of the wheel cover


10


, respectively. The spinning machine


26


includes a base


28


. An air cylinder


30


moves a central rod


32


axially. The central rod


32


includes a fixture element or nest


33


which secures the wheel cover


10


to the central rod


32


. More specifically, the fixture element


33


locks the wheel cover


10


in place to be spun by the spinning machine


26


. The central rod


32


depends from a frame


35


which is secured to the base


28


. The frame


35


attaches to and/or holds a top end


37


of the central rod


32


in place. The air cylinder


30


is secured to the top of the frame


35


. The air cylinder


30


is used to rotate or spin the fixture element


33


and the wheel cover


10


relative to the base


28


. By positioning the fixture element


33


longitudinally, the spinning machine


26


may spin several discs


12


of different size and contour.




A rotating pedestal


39


supports and rotates the wheel cover


10


from below the wheel cover


10


and the fixture element


33


. A motor (not shown) is housed within the base


28


. The motor drives the rotating pedestal


39


using a belt drive (not shown) as is known in the art. Because the wheel cover


10


is secured to the rotating pedestal


39


, the fixture element


33


, the central rod


32


and the cylinder


30


all spin with the motor.





FIGS. 2A and 2B

represent two steps in the method as the wheel cover


10


is being fabricated. In

FIG. 2B

, an internal lock roller


34


and an external lock roller


36


are shown. In

FIG. 2A

, an internal wrap roller


38


and an external wrap roller


40


are shown. As distinguished from the prior art cited above, the rollers


34


,


36


,


38


,


40


neither stamp a roll in the outer edge


20


of the wheel cover


10


nor do they stamp the lock


42


therein. The roller assemblies


34


,


36


,


38


,


40


are rotated by engaging a spinning wheel cover


10


. By slowly forcing the rollers


34


,


36


,


38


,


40


into the wheel cover


10


, the disc


12


is bent or moved back along the contour of the rollers


34


,


36


,


38


,


40


, discussed subsequently. Arms


41


,


43


,


45


,


47


hold the rollers


34


,


36


,


38


,


40


in proper alignment, respectively. Air cylinders


49


,


51


,


53


,


54


may be used to move the arms


41


,


43


,


45


,


47


into and out of engagement with the wheel cover


10


.




When generating a lock


42


, as best seen in

FIGS. 2B and 4

, the internal lock roller


34


engages the outboard surface


16


of the disc


12


. The external lock roller


36


engages the inboard surface


18


. The relative movement between the external lock roller


36


and the internal lock roller


34


forces the disc


12


to conform to the profiles of the lock rollers


34


,


36


. Because the disc


12


is fabricated from a non-resilient material, the disc


12


will maintain the form of the lock rollers


34


,


36


after they have disengaged the disc


12


. The result of this step is the formation of the lock


42


which is disposed adjacent the outer edge


20


. The lock


42


coacts with a catch


44


on the outboard surface


24


of the wheel


19


allowing the wheel cover


10


to be secured to the wheel


19


.




When generating a wrap


46


in the wheel cover


10


, the internal wrap roller


38


and external wrap roller


40


are moved relatively with respect to the wheel cover


10


. The external wrap roller


40


engages the outer rim flange


21


and allows it to conform to the profile permitted by the external wrap roller


40


as the wheel cover


10


is spun by the motor. A bottom portion


48


of the external wrap roller


40


starts the creation of the wrap


46


. A body portion


50


of the external wrap roller


40


guides the wrap


46


as the external wrap roller


40


is moved inwardly against the wheel cover


10


. The arm


47


moves the external wrap roller


40


into and out of engagement with the wheel cover


10


using the air cylinder


54


. A plurality of wrap rollers


38


,


40


may be used. While the wrap


46


extends around a rim edge


52


of the outer rim flange


21


, it is not used as a locking mechanism. It is aesthetic in nature as it covers the outer rim flange


21


.




The method for fabricating the wheel cover


10


for permanent attachment to a wheel


19


having an outer rim flange


21


includes the step of forming a disc


12


from a sheet of metal. The disc


12


defines the outboard surface


16


, the inboard surface


18


, and the outer edge


20


. The disc


12


also defines a central axis which is coaxial with the axis


55


of the central rod


32


. The disc


12


is then stamped to bend the disc


12


through three dimensions. The disc


12


is stamped so that it may have a contour which is desired. Further, the disc


12


must have a contour capable of being received by the wheel


19


. The contouring of the disc


12


changes the disc


12


from a two-dimensional object to a three-dimensional object.




Once the disc


12


is stamped, the disc


12


is mounted to the fixture element


33


which may or may not be already mounted to the central rod


32


of the spinning machine


26


. Once mounted to the fixture element


33


and the fixture element


33


is mounted to the central rod


32


using a fastening structure


56


, the central rod


32


is rotated by the motor. The rotation of the central rod


32


spins the disc


12


about its axis which is now aligned with the central axis


55


of the central rod


32


.




Once the disc


12


is spinning at a desired speed, a force is applied to the disc


12


while the disc


12


continues to spin. This force is generated by the internal lock roller


34


and the external lock roller


36


. The force applied to the disc


12


generates the lock


42


. The lock generation is shown in FIG.


4


. Once the lock


42


is created, the internal lock roller


34


and the external lock roller


36


are moved out of engagement with the disc


12


.




The wrap


46


is generated subsequent to the generation of the lock


42


. The wrap rollers


38


,


40


engage the outer edge


20


and the portion of disc


12


disposed immediately adjacent the outer edge


20


. The force applied to the outer edge


20


forces the outer edge


20


to bend over the inboard surface


18


to create the wrap


46


to be eventually received by the outer rim flange


21


of the wheel


19


.




The force being applied to the outer edge


20


of the disc


12


is accomplished by moving the external wrap roller


40


radially into the outer edge


20


in a direction perpendicular to the central axis


55


of the central rod


32


and the rotating pedestal


39


. Support for the disc


12


is provided by the internal wrap roller


38


which may be moved radially outwardly. The outer edge


20


follows the contour of the wrap generating rollers


38


,


40


. Therefore, by selecting the rollers


34


,


36


,


38


,


40


with a specific circumferential profile or contour, specific lock and wrap profiles are also being selected. Although not shown, rollers


34


,


36


,


38


,


40


having circumferential contours which are different from each other may be selected if the wrap profile is complex.




Once the wrap


46


has been created, the wrap rollers


38


,


40


are removed from the disc


12


. It may be appreciated that any number of roller combinations may be used. However, an even number of roller combinations diametrically opposed would stabilize the disc


12


while it was being spun by the spinning machine


26


. An odd number of roller combinations or an even number of roller combinations which are not diametrically opposed would result in an uneven creation of the wrap


46


at the outer edge


20


of the wheel cover


10


.




After the wheel cover


10


has stopped spinning, it is removed from the spinning machine


26


. The wheel cover


10


may then be secured to the wheel


19


according to methods known to those skilled in the art. One such method is disclosed in U.S. Pat. No. 5,461,779 which is hereby incorporated by reference. The wrap


46


is not created around the outer rim flange


21


of the wheel


19


. It is designed to receive the outer rim flange


21


therein only after it has been created.




The invention has been described in an illustrative manner. It is to be understood that the terminology which has been used is intended to be in the nature of words of description rather than of limitation.




Many modifications and variations of the invention are possible in light of the above teachings. Therefore, within the scope of the appended claims, the invention may be practiced other than as specifically described.



Claims
  • 1. A method for fabricating a wheel cover for permanent attachment to a wheel having an outer rim flange, the method comprising the steps of:securing the wheel cover to a spinning machine; spinning the wheel cover about the central axis; applying a lock generating force directed radially to an outboard surface of the wheel cover while the wheel cover is spinning to generate a mechanical lock to engage the wheel; applying a wrap generating force to an outer edge and the outboard surface of the wheel cover while the wheel cover is spinning to force the outer edge to bend over the inboard surface to create a wrap to be received by the outer rim flange of the wheel.
  • 2. A method as set forth in claim 1 wherein the step of applying a lock generating force includes the step of moving a roller radially outwardly into the outboard surface of the wheel cover.
  • 3. A method as set forth in claim 2 wherein the step of applying a wrap generating force includes the step of moving a roller radially inwardly into the outer edge of the wheel cover and engaging the outboard surface of the wheel cover.
  • 4. A method as set forth in claim 3 including the step of removing the roller from the disc after a wrap has been created.
  • 5. A method as set form in claim 4 including the step of removing the roller from the disc after a lock has been created.
  • 6. A method as set form in claim 1 wherein the steps of applying a lock generating force and a wrap generating force include the steps of moving a plurality of rollers into the outer edge and the outboard surface of the wheel cover.
  • 7. A method for fabricating a wheel cover for permanent attachment to a wheel having an outer rim flange, the method comprising the steps of:securing the wheel cover to a spinning machine; spinning the wheel cover about the central axis; and applying a lock generating force between rollers to an outboard surface of the wheel cover while the wheel cover is spinning to generate a mechanical lock to engage the wheel.
  • 8. A method for fabricating a wheel cover for permanent attachment to a wheel having an outer rim flange, the method comprising the steps of:securing the wheel cover to a spinning machine; spinning the wheel cover about the central axis; and applying a wrap generating force between rollers to an outer edge and the outboard surface of the wheel cover while the wheel cover is spinning to force the outer edge to bend over the inboard surface to create a wrap having a cavity to receive the outer rim flange of the wheel.
US Referenced Citations (5)
Number Name Date Kind
2057565 Eksergian Oct 1936
3025819 Lyon Mar 1962
3214220 Foster et al. Oct 1965
4094550 Toal et al. Jun 1978
5072509 Bichel et al. Dec 1991
Foreign Referenced Citations (1)
Number Date Country
38905 Aug 1965 DE