Abstract:
A heeling apparatus includes a shoe with a unique feature in the heel that allows one to walk, run, or roll seamlessly. The appearance is that of normal footwear because of the covert wheel assembly. The stealth wheel in the heel gives one the ability to roll or slide in areas you could only walk. Heeling is a new activity that employs a unique method of rolling and requires a newly learned skill set of balance, positioning, and coordination.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]    Pursuant to 35 U.S.C. § 120, this continuation application claims priority from, and hereby incorporates by reference for all purposes, copending U.S. patent application Ser. No. 09/930,318, entitled Heeling Apparatus and Method, naming Roger R. Adams as inventor, filed Aug. 14, 2001, which is a divisional patent application and claims priority from copending U.S. patent application Ser. No. 09/540,125, entitled Heeling Apparatus and Method, naming Roger R. Adams as inventor, filed Mar. 31, 2000, which, pursuant to 35 U.S.C. § 119(e), claims the benefit of U.S. Provisional Patent Application Serial No. 60/127,459, entitled Heeling Apparatus and Method, naming Roger R. Adams as inventor, filed Apr. 1, 1999. 
     
    
     
       TECHNICAL FIELD OF THE INVENTION  
         [0002]    This invention relates in general to the field of footwear and active sports and more particularly to a heeling apparatus and method.  
         BACKGROUND OF THE INVENTION  
         [0003]    Action or extreme sports include various sports such as, for example, skateboarding, snow boarding, in-line skating, rock climbing, and skydiving. Most action or extreme sports require expensive and cumbersome equipment that can only be used in select and, often, limited areas. Because these select and limited areas are not convenient to most people, these activities can only be enjoyed at select times. This results in a substantial investment in equipment that is only used sporadically, when large blocks of time are available to travel to such select and limited areas available for the activity. Because of these limitations and inconveniences, many times interest in the activity wanes.  
         SUMMARY OF THE INVENTION  
         [0004]    The present invention presents the rare opportunity to create an entirely new sport and activity with mass appeal that does not suffer from the disadvantages, limitations, and problems mentioned above. From the foregoing it may be appreciated that a need has arisen for a heeling apparatus and related methods to create the foundation for a new action or extreme sport that can be pursued in many locations and conditions without the need for a large investment in equipment.  
           [0005]    According to one aspect of the present invention, a heeling apparatus is provided that includes a footwear having an opening in a sole, such as the heel portion of the sole, to receive a wheel assembly, and a wheel assembly positioned in the opening of the sole of the footwear. The wheel assembly may include an axle, a wheel mounted on the axle, and a mounting structure operable to support the axle. In alternative embodiments, the wheel assembly includes only the wheel mounted on the axle without the need for the mounting structure. In other embodiments, the mounting structure is integrated or included as part of the opening in the sole of the footwear.  
           [0006]    According to another aspect of the present invention a wheel/axle assembly for use in a wheel assembly of a heeling apparatus is provided that includes a wheel, a first bearing, a second bearing, and an axle. The wheel has an axle opening, a first annular recess on a first side of the wheel that surrounds the axle opening on the first side, and a second annular recess on a second side of the wheel that surrounds the axle opening on the second side. The first bearing is positioned in the first annular recess on the first side of the wheel, and the second bearing is positioned in the second annular recess on the second side of the wheel. The axle is positioned within the axle opening of the wheel such that the wheel is rotatably coupled to the axle through the first bearing and the second bearing.  
           [0007]    According to yet another aspect of the present invention, a method for using a heeling apparatus on a surface is provided that includes running on a surface by using a forefoot portion of a sole of the heeling apparatus to contact the surface, and rolling on the surface with a wheel of the heeling apparatus extended below the bottom of the sole through an opening in the sole by using a wheel of the heeling apparatus to contact the surface.  
           [0008]    According to a still further aspect of the present invention, a method for making a heeling apparatus is provided that includes providing a footwear that includes a sole, forming an opening in the sole of the footwear that extends to a bottom surface of the sole, and positioning a wheel assembly in the opening of the sole of the footwear.  
           [0009]    The present invention provides a profusion of technical advantages that include the capability of the heeling apparatus to function as normal, comfortable footwear for walking, and even running, and to function as rolling footwear, which may be referred to only herein as “heeling.” 
           [0010]    Another technical advantage of the present invention includes the capability to implement the invention using virtually any available footwear such as, for example, conventional shoes, boots, dress shoes, loafers, sandals, slippers, bindings, and the like. Conventional footwear may be incorporated into a heeling apparatus by, preferably, forming or cutting an opening in the heel portion of the sole of such conventional footwear. Thus, the present invention may be implemented using conventional footwear that appears externally, during normal use, as conventional footwear. This allows the present invention to be practiced as a “stealth” or “covert” activity because, from external appearances, it is being performed using conventional footwear. In a preferred embodiment of the present invention, the sole of conventional athletic shoes may be used in the present invention without the need to design awkward looking thick soled shoes to house the wheel.  
           [0011]    A further technical advantage of the present invention includes the capability to implement the present invention with other active sport accessories such as in a grind shoe, such as the grind shoe made by SOAP, which also provides grinding or sliding functionality.  
           [0012]    Yet another technical advantage includes the capability to use the present invention to enjoyably obtain an overall aerobic workout.  
           [0013]    Still yet another technical advantage of the present invention includes the capability of enhanced control for turning and maneuvering, while still providing durability, reliability, and mechanical strength. The present invention provides this durability and reliability in harsh environments and with heavy and demanding use, including the capability to withstand the forces of jumps, spins and maneuvers of all kinds.  
           [0014]    Another technical advantage includes capability of removable wheels and axles so that bearings may be easily changed and maintained and so that different types of wheels, bearings, and axles may be used as desired by the user and as dictated by the conditions.  
           [0015]    In yet a further technical advantage of the present invention includes a wheel/axle assembly that can be easily inserted or removed from a wheel assembly or mounting structure, such as by using a friction fit. In other embodiments, the wheel assembly, or heeling apparatus, includes the capability of a retractable wheel. This allows a user to quickly and conveniently convert from using the heeling apparatus as normal footwear into using the heeling apparatus for “heeling.” The wheel is moved from a retracted position in the sole or heel of the heeling apparatus to an extended position where at least a portion of the wheel is exposed below the sole for rolling. The retractable wheel may be implemented using any number of designs and/or configurations such as a king pin arrangement, a dual position arrangement using a collapsible axle, a hinged arrangement, or even a spring arrangement.  
           [0016]    Other technical advantages are readily apparent to one skilled in the art from the following figures, description, and claims.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0017]    For a more complete understanding of the present invention and the advantages thereof, reference is now made to the following brief description, taken in connection with the accompanying drawings and detailed description, wherein like reference numerals represent like parts, in which:  
         [0018]    [0018]FIG. 1 is a side view that illustrates a heeling apparatus implemented using an athletic shoe according to one embodiment of the present invention;  
         [0019]    [0019]FIGS. 2A and 2B are bottom views that illustrate two embodiments of a sole of the heeling apparatus with openings in the sole;  
         [0020]    [0020]FIGS. 3A and 3B are bottom views of the two embodiments of the sole as shown in FIGS. 2A and 2B and illustrate a wheel in each of the openings of the soles;  
         [0021]    [0021]FIG. 4 is a perspective view that illustrates a wheel rotatably mounted to an axle, which also may be referred to as a wheel/axle assembly, for use in a wheel assembly according to one embodiment of the present invention;  
         [0022]    [0022]FIG. 5 is a perspective view that illustrates a mounting structure for use with a wheel rotatably mounted to an axle, as illustrated in FIG. 4, to form a wheel assembly;  
         [0023]    [0023]FIG. 6 is a bottom view that illustrates a wheel assembly that includes the wheel rotatably mounted on the axle as shown in FIG. 4 and the mounting structure of FIG. 5;  
         [0024]    [0024]FIG. 7 is a side view that illustrates the wheel assembly positioned above and through the opening in a footwear to form a heeling apparatus;  
         [0025]    [0025]FIGS. 8A, 8B,  8 C, and  8 D are profile views of various wheels that illustrate the surface profile of these wheels that may used in various embodiments of the present invention;  
         [0026]    [0026]FIG. 9 is a perspective view that illustrates a mounting structure of another embodiment for use in a wheel assembly of a heeling apparatus;  
         [0027]    [0027]FIG. 10 is a perspective view that illustrates a wheel assembly that uses yet another embodiment for use in a heeling apparatus;  
         [0028]    [0028]FIG. 11 is a side, partial cutaway view that illustrates one embodiment of a heeling apparatus that illustrates the wheel assembly provided in the sole of the heeling apparatus and the opening in the sole not extending completely through the sole;  
         [0029]    [0029]FIG. 12 is a side view of another embodiment that illustrates the heeling apparatus of the present invention with a removable wheel cover positioned to cover the wheel and the opening in the sole;  
         [0030]    [0030]FIG. 13 is a bottom view that illustrates another embodiment of the present invention with a spherical ball serving as a wheel and positioned in a mounting structure in an opening in the heel portion of the sole;  
         [0031]    [0031]FIG. 14 is a perspective view that illustrates a “heeler” using the present invention to “heel”;  
         [0032]    [0032]FIG. 15 is a perspective view that illustrates a wheel rotatably mounted to an axle, which also may be referred to as a wheel/axle assembly, similar to FIG. 4;  
         [0033]    [0033]FIG. 16 is a cutaway view that illustrates a collapsible axle of the wheel/axle assembly of FIG. 15 implemented as a spring loaded collapsible axle;  
         [0034]    [0034]FIG. 17 is a perspective view that illustrates another mounting structure for use with the wheel/axle assembly and the collapsible axle, as illustrated in FIG. 15 and FIG. 16, to form a wheel assembly;  
         [0035]    [0035]FIG. 18 is a side, cutaway view that illustrates a wheel assembly positioned through an opening in a sole that illustrates one embodiment of an axle that couples to the mounting structure to provide a retractable wheel using an assembly that may be referred to as a king pin arrangement;  
         [0036]    [0036]FIG. 19 is a bottom view that illustrates the wheel assembly of FIG. 18 that further illustrates the dual king pin arrangement;  
         [0037]    [0037]FIG. 20 is a side view that illustrates one member of the mounting structure that further illustrates the coupling of the axle to the mounting structure using the dual king pin arrangement; and  
         [0038]    [0038]FIG. 21 is a breakaway and perspective view that illustrates a two piece wheel that includes an inner core and an outer tire and that may be used in the present invention.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0039]    It should be understood at the outset that although an exemplary implementation of the present invention is illustrated below, the present invention may be implemented using any number of techniques, materials, designs, and configurations whether currently known or in existence. The present invention should in no way be limited to the exemplary implementations, drawings, and techniques illustrated below, including the exemplary designs and implementations illustrated and described herein.  
         [0040]    It should be understood at the outset that although exemplary implementations of the present invention are illustrated below, the present invention may be implemented using any number of mechanisms, arrangements, structures, and/or techniques. Thus, the present invention should in no way be construed to be limited to the exemplary implementations, drawings, and techniques illustrated and described herein.  
         [0041]    [0041]FIG. 1 is a side view of a heeling apparatus  10  implemented using an athletic shoe  12  according to one embodiment of the present invention. The heeling apparatus  10  preferably includes a wheel assembly provided in an opening in the heel portion of the sole of a footwear. For example the athletic shoe  12  includes an opening in the bottom of a heel portion  18  of a sole  14  with a wheel assembly provided in the hole such that a wheel  16  extends below the bottom of the sole  14 . The wheel assembly preferably includes at least one wheel, such as the wheel  16 , rotatably mounted on an axle (not illustrated in FIG. 1). The wheel  16  mounted on the axle is preferably positioned in the opening of the sole  14  through a mounting structure (not illustrated in FIG. 1) that is operable to support the axle such that a portion of the wheel  16  extends below the heel portion  18  of the sole  14 .  
         [0042]    The amount or length of the portion of the wheel  16  that extends below the bottom of the sole  14 , as defined by a distance  24 , will preferably be less than the diameter of the wheel  16 . The distance  24 , however, may be greater than, less than, or equal to the diameter of the wheel  16 .  
         [0043]    The athletic shoe  12 , as is true of most footwear, may be generally described as having the sole  14  and an upper part  26 . The upper part  26  may be constructed of virtually any material such as, for example, leather, plastic, or canvas. The sole  14  may include three parts: (1) an inner sole or insole (not illustrated in FIG. 1); (2) a midsole  28 ; and (3) an outer sole or outsole  30 . The insole may provide added cushion and may or may not be removable. In some embodiments, the insole may include a removable portion, such as a DR. SCHOLL&#39;S insole, and a portion that remains attached to the athletic shoe  12 . The outsole  30  will preferably be made of a durable material, such as rubber, and may have a textured surface, such as with knobbies, to provide added traction. The midsole  28  will generally be constructed of a soft or “cushiony” material and will generally be thicker than the insole and the outsole  30 . In some embodiments, however, the sole  14  will comprise only one part, such as the leather sole of a loafer. In other embodiments, the sole  14  may include a separate heel block or object that elevates the footwear, such as the heel of a leather wingtip dress shoe. This heel block or object may be considered to be part of the heel portion  18  of the sole  14 . It should be understood that the present invention may be implemented in virtually any footwear, irrespective of the design or the make-up of the sole  14 . Various styles of footwear and methods of making footwear are known in the art and are known by one of ordinary skill in the art. For example, U.S. Pat. Nos. 4,245,406, 5,319,869, 5,384,973, 5,396,675, 5,572,804, 5,595,004, and 5,885,500, which are hereby incorporated by reference for all purposes, provide various background information regarding various footwear and methods of making footwear.  
         [0044]    In most footwear, including the athletic shoe  12 , the sole  14  may also be divided into three portions or regions: (1) the heel portion  18 , (2) an arch portion  20 , and (3) a forefoot portion  22 , as illustrated in FIG. 1. It should be understood that the heel portion  18 , the arch portion  20 , and the forefoot portion  22  of the sole  14  are incapable of being exactly defined and located, and that such portions vary from one footwear type to another. Thus, the location, the boundaries between, and the size of the heel portion  18 , the arch portion  20 , and the forefoot portion  22  of the sole  14  are only rough approximations.  
         [0045]    It should also be understood that although the position of the opening in the bottom of the sole  14 , and hence also the wheel  16 , is preferably located in the heel portion  18  of the sole  14 , such an opening may also be located at the boundary of the heel portion  18  and the arch portion  20 , at the arch portion  20 , or at virtually any other location on the sole  14 . The opening in the bottom of the sole  14  may extend entirely through the sole  14 , e.g., through the outsole, the midsole and the insole, or only partially through the sole  14 , e.g., through the outsole, and a portion or all of the midsole.  
         [0046]    The wheel  16  may be constructed or made of virtually any known or available material such as, for example, a urethane, a plastic, a polymer, a metal, an alloy, a wood, a rubber, a composite material, and the like. This may include, for example, aluminum, titanium, steel, and a resin. Preferably, the material will be durable, provide quiet performance, and will provide a “soft” or “cushioning” feel. In one embodiment, the wheel  16  may be implemented as one or more precision bearings such that the precision bearing serves as the wheel  16  itself. In yet another embodiment, the wheel assembly may include a spring or suspension such as, for example, a leaf spring, to provide additional cushion or suspension when the wheel  16  contacts a surface and a force is applied to the athletic shoe  12  in the direction of the surface, such as when a someone is wearing and walking in the heeling apparatus  10 . The spring is preferably provided as part of the mounting structure of the wheel assembly. In still another embodiment, the wheel  16  is provided as a two piece wheel with an inner core, such as a hard inner core, such as a hard inner core, surrounded by an outer tire, such as a urethane tire.  
         [0047]    Depending on the desired implementation, the wheel  16  and the axle may be removable from the wheel assembly. In such a case, a removable cover may be provided in the opening in the sole  14  to cover the opening so that debris and dirt does not enter the opening. The removable cover may be provided in virtually any available configuration readily ascertainable by one of ordinary skill in the art. In one embodiment of the removable cover, an axle portion of the removable cover fits and/or couples to the mounting structure in the same or similar manner that the axle in which the wheel  16  is mounted fits and/or couples to the mounting structure of the wheel assembly. A tool may also be provided to facilitate the removal of the axle and wheel  16 . This tool will, preferably, be small and multi-functional to provide any other possible adjustments to the heeling apparatus  10 , such as a screw driver, a wrench, and the like. In other embodiments of the heeling apparatus  10 , the wheel  16  may be retractable into the opening in the sole  14 . In this manner, the wheel  16  may be retracted into the sole  14  and, thus, will not extend below the bottom of the sole  14 . This allows the heeling apparatus  10  to function just like ordinary footwear, such as the athletic shoe  12 .  
         [0048]    In one embodiment of the present invention, the wheel assembly does not include an axle, and, arguably, not a mounting structure, and the wheel  16  is provided as a sphere, such as a stainless steel ball bearing, that is rotatably positioned in the opening in the bottom of the heel portion  18  of the sole  14 , one embodiment of which is shown in FIG. 13. In another embodiment, the wheel assembly comprises an axle positioned completely through or partially through the heel portion  18  of the sole  14  such that the sole  14  supports the axle and the wheel is rotatably mounted on the axle in the opening of the sole  14 . In this manner, the need for the mounting structure is eliminated.  
         [0049]    In operation, a person wearing the heeling apparatus  10  may either walk normally or roll on the wheel  16  by lifting or raising the sole  14  so that only or almost only the wheel  16  contacts a surface. This action may be referred to as “HEELING” or to “HEEL.” The wheel  16 , depending on the desired implementation of the present invention, may be removed or retracted to a position such that the wheel  16  does not extend below the bottom of the sole  14 . This, generally, will result in the heeling apparatus  10  performing like an associated footwear. When the wheel  16  is removed or retracted, a removable cover may be placed over the opening in the bottom of the sole  14  to prevent debris from entering the opening and potentially damaging the wheel assembly. In still other embodiments, a removable cover may be placed over the wheel  16  while a portion of the wheel  16  remains extended below the bottom of the sole  14  to assist with walking, an example of this is illustrated in FIG. 12.  
         [0050]    It should be understood, however, that even if the wheel  16  is not removed or retracted as just described, the user may still comfortably walk and run, even with the wheel  16  extended. This generally occurs because the distance  24  can be minimal, which provides a unique “stealth” or “covert” aspect to heeling. This also results in the wheel rolling the opening or hole in the sole  14  of the heeling apparatus  10 . In one embodiment, the distance  24  is less than the radius of the wheel  16 , which results in most of the wheel residing within the opening of the sole  14 .  
         [0051]    [0051]FIGS. 2A and 2B are bottom views of two embodiments of the sole  14  of the heeling apparatus  10 . In particular, the outsole  30  or bottom of the sole  14  is illustrated in FIG. 2A with an opening  40  in the heel portion  18  of the sole  14 . In the embodiment illustrated, the opening  40  is provided in a square or rectangular configuration. The opening  40 , however, may be provided in virtually any configuration, such as, for example, a circular or an elliptical configuration.  
         [0052]    As mentioned previously, the opening  40  may extend partially or completely through the sole  14 . The opening  40  may be provided through a heel block or object. Further, the opening  40  be positioned in, near, or in a combination of the heel portion  18 , the arch portion  20 , and the forefoot portion  22 .  
         [0053]    [0053]FIG. 2B illustrates a second embodiment as to the placement and configuration of the opening  40 . The outsole  30  is illustrated with an opening  40 A and an opening  40 B in the heel portion  18  of the sole  14 . In this manner, one or more wheels, including one or more axles, may be positioned in both the opening  40 A and  40 B.  
         [0054]    [0054]FIGS. 3A and 3B are bottom views of the two embodiments of the sole  14  as shown in FIGS. 2A and 2B and illustrate a wheel in each of the openings of the soles. This includes a wheel  42  positioned in the opening  40  in FIG. 3A and a wheel  42 A and a wheel  42 B in the openings  40 A and  40 B, respectively, of FIG. 3B.  
         [0055]    The wheel  42  and the wheels  42 A and  42 B are illustrated as cylindrical wheels. These wheels, however, may be provided in virtually any available configuration. Further, one or more wheels may be positioned in each opening.  
         [0056]    [0056]FIG. 3A further illustrates other elements of the wheel assembly that include a first member  48  and a second member  54  of a mounting structure that is used to removably couple with an axle  50 . The axle  50  extends through the wheel  42  such that the wheel  42  is rotatably coupled or mounted to the axle  50 . This preferably involves the use of precision bearings, such as high performance precision bearings, provided in a recess, such as an annular recess, on either side of the wheel  42 . A first precision bearing  56  and a second precision bearing  58  may be ABEC grade precision bearings and are illustrated with hidden lines and positioned in the first recess and second recess of the wheel  42 . In alternative embodiment, loose ball bearings may be used.  
         [0057]    The axle  50  may be made of any material that provides suitable physical characteristics, such as strength and weight, to name a few. The axle  50  is preferably made of hardened steel, is cylindrical in shape, each end is rounded, and is removably coupled with a first member  48  and a second member  54 , respectively, of the mounting structure. The removable coupling between each end of the axle  50  and the first member  48  and the second member  54  may be achieved by any known or available mechanism. In a preferred embodiment, a sphere or a ball bearing, preferably using a moveable spring and/or a screw bias, is used to contact and exert a side wall force between one or members of the mounting structure and the axle  50 .  
         [0058]    It should also be noted that because the weight of the user of the heeling apparatus  10  will exert a significant downward force and the ground or surface will exert an equal force upward, the axle  50 , and, hence, the wheel  42  will generally be forced into place. Only when the heel is raised from a surface will any force or friction be required to keep the axle  50  in place. Thus, the present invention does not require a large side force to keep the axle  50  and the wheel  42  in place. The recognition of this fact may be considered an aspect of the present invention for the embodiment as showm. This recognition allows the removable coupling between each end of the axle  50  and the first member  48  and the second member  54  to be optimally designed.  
         [0059]    [0059]FIG. 3A also illustrates a grind plate  44  (which also may be referred to as a slide plate  44 ) that may be used in conjunction with the heeling apparatus  10  of the present invention. The grind plate  44  provides a smooth or relatively smooth surface to allow a user to “grind” or “slide” on various surfaces such as hand rails, curbs, steps, corners, and the like. The grind plate  44  is preferably somewhat thin and made of a plastic or polymer material. In a preferred embodiment, the grind plate  44  is removably attached to the arch portion  20  of the outsole  30  of the sole  14 . The grind plate  44  may be attached using any known or available fastener, such as, for example, a fastener  46  shown in various locations around the periphery of the grind plate  44 .  
         [0060]    [0060]FIG. 3B further illustrates an axle  52  in which the wheel  42 A and the wheel  42 B are coupled to either end in the opening  40 A and the opening  40 B, respectively. The axle  52  extends through both the wheels  42 A and  42 B and through a portion of sole  14 , not visible in FIG. 3B. This serves to support the axle  52  and illustrates the situation where the sole  14  serves as the mounting structure of the wheel assembly. This reduces the overall number of parts. In an alternative embodiment, a metal or some other suitable material may be used within the heel portion  18  of the sole  14  where the axle  52  is positioned to provide additional support and stability. This is an example where the mounting structure is, in effect, integrated into the sole  14 . As can be appreciated by one skilled in the art, the present invention may be implemented in any number of ways.  
         [0061]    [0061]FIG. 4 is a perspective view of a wheel  60  rotatably mounted on an axle  62 , which also may be referred to as a wheel/axle assembly, for use in a wheel assembly, or in a heeling apparatus, according to one embodiment of the present invention. The wheel  60  and the axle  62  may also be referred to as a wheel/axle assembly  400 . In this embodiment, the axle  62  extends through the wheel  60  and includes two ends that are rounded or bullet shaped. A precision bearing  64  is shown positioned in a recess, which is shown as an annular recess, of the wheel  60  to facilitate the rotation of the wheel  60  around the axle  62 . Preferably a second precision bearing is positioned in a second recess, not shown in FIG. 4, to further facilitate such rotation.  
         [0062]    A slip clip, slip ring, or ring clip  66  is shown positioned around, or nearly around, the axle  62  near the precision bearing  64 . This serves to ensure that the precision bearing  64  remains in place in the recess of the wheel  60 . The slip clip or ring clip  66  will preferably be positioned on the axle  62  through a groove, such as a radial groove or radial indentation, in the axle  62 . It should be understood, however, that one of ordinary skill in the art may use any of a variety of other arrangements to ensure that the precision bearing  64  stays in position. In alternative embodiments, the precision bearing  64  may be eliminated or loose bearings may be used.  
         [0063]    The wheel  60  rotatably mounted on the axle  62  may, in alternative embodiments, serve as the wheel assembly of the present invention. In such a case, the axle  62  may be mounted to the sole, such as the midsole and heel portion, at its ends while the wheel  60  is rotatably provided in the opening of the sole. In this manner, the need for a mounting structure may be thought of as eliminated or, alternatively, the mounting structure may be thought of as integrated into the sole of the footwear.  
         [0064]    [0064]FIG. 5 is a perspective view of a mounting structure  70  for use with a wheel rotatably mounted to an axle, such as is illustrated in FIG. 4, to form a wheel assembly. The mounting structure  70  generally includes a heel control plate  72 , a first member  74 , and a second member  76 . In alternative embodiments, a spring, such as a leaf spring, could be provided where the two members contact the heel control plate  72 . This would provide the added benefit of greater cushion and suspension. The two members include an opening, such as the opening  78  of the first member  74  to receive an end of an axle. It should be mentioned that the opening may be provided in virtually any configuration, including extending through the member, or placed at different positions, or even multiple positions for mounting the wheel/axle assembly  400  at a retractable position and an extended position, on the member.  
         [0065]    The axle that is to be positioned in the openings of the first member  74  and the second member  76  will preferably be removably coupled. This may be achieved by any number of arrangements and configurations, all of which fall within the scope of the present invention. One such arrangement is the screw/spring/ball bearing arrangement  80  provided in first member  74 . This arrangement provides an adjustable bias or force that can be exerted against the axle when it is inserted into the opening  78 . The screw is accessible and adjustable by the user. The turning of the screw affects the compression of a spring which, in turn, provides a force on a ball bearing that extends out into the opening  78 . When the axle is inserted into the opening  78 , the ball bearing may be displaced an amount and the screw/spring/ball bearing arrangement  80  will provide a side force to allow the axle to be secure, yet removable. A similar arrangement may also be provided in the second member  76  to provide a friction fit or coupling on the other end of the axle  62 .  
         [0066]    Although the screw/spring/ball bearing arrangement  80  of FIG. 5 is shown being implemented through a horizontal opening in the first member  74 , it may be implemented in using an opening aligned in virtually in manner in the member. For example, the adjustment of the tension or pressure on the screw/spring/ball arrangement  80  may be achieved through a diagonal opening such that the exposed end of the screw/spring/ball arrangement  80 , normally a screw head end, is provided where the reference line for numeral  74  in FIG. 5 contacts the first member  74 . This provides easier access to adjust the tension and friction fit on the axle  62  when the wheel assembly, such as wheel assembly  100  of FIG. 6, is engaged or positioned within the opening of a sole to form a heeling apparatus. Of course, any of a variety of other arrangements, configurations, and opening alignments may be contemplated and implemented under the present invention.  
         [0067]    The mounting structure  70  can be made or constructed of virtually any material, generally depending on the desired mechanical characteristics such as, for example, rigidity and strength. These materials may include, for example, a plastic, a polymer, a metal, an alloy, a wood, a rubber, a composite material, and the like. This may include aluminum, titanium, steel, and a resin. In one embodiment, the mounting structure  70  is made of a metal, such as aluminum, that has been anodized such that the mounting structure  70  presents a black color or hue.  
         [0068]    [0068]FIG. 6 is a bottom view of a wheel assembly  100  that includes the wheel  60  rotatably mounted to the axle  62 , as shown in FIG. 4, and the mounting structure  70  of FIG. 5. The first member  74  and the second member  76  each removably couple with the ends of the axle  62  through a bias mechanism implemented using a bias mechanism, such as the screw/spring/ball bearing arrangement  80 . A ball bearing  102  is shown contacting one end of the axle  62  in the opening  78 . Further slip clips or ring clips (which may also be referred to as snap rings or slip rings), such as ring clip  66 , are provided to ensure that the precision bearings positioned in the recesses of the wheel remain in position.  
         [0069]    The heel control plate  72  allows the user of the heeling apparatus to gain greater control and to obtain greater performance out of the heeling apparatus.  
         [0070]    [0070]FIG. 7 is a side view of the wheel assembly  100  positioned above and through the opening to form a heeling apparatus  120 . The heel control plate  72  resides inside the shoe so that the heel of the user may apply pressure to the heel control plate as desired to provide better handling and performance of the heeling apparatus  120 .  
         [0071]    [0071]FIGS. 8A, 8B,  8 C, and  8 D are profile views of various wheels  200  that illustrates the surface profile of these wheels that may used in various embodiments of the present invention. In FIG. 8A, a wheel  202  is shown with a flat or square surface or exterior profile  204 . In FIG. 8B, a wheel  206  is shown with an inverted surface profile  208 . In FIG. 8c, a wheel  210  is shown with round surface profile  212 . Finally, in FIG. 8D, a wheel  214  is shown with a steep surface profile  216 . The present invention may incorporate virtually any available surface profile of a wheel.  
         [0072]    [0072]FIG. 9 is a perspective view that illustrates a mounting structure  500  of another embodiment for use in a wheel assembly of a heeling apparatus. The mounting structure  500  includes an axle  502 , which may be considered one axle that extends through and is mounted through a member  50  or as an axle  502  that couples with the member  506  along with an axle  504  that couples with the member  506  opposite axle  502 . The mounting structure  500  also includes a heel control plate  508  coupled with the member  506 .  
         [0073]    The mounting structure  500  allows for two wheels to be mounted to form a wheel assembly. A wheel may be rotatably mounted on the axle  502 , preferably using a precision bearing, and a wheel may be rotatably mounted on the axle  504 , also preferably through a precision bearing as illustrated previously herein.  
         [0074]    The axle  502  and the axle  504  include a threaded portion such that a nut, such as a lock nut  510  may be included to secure a wheel to each axle. In other embodiments, the end of the axles may include internal threads, as opposed to external threads as shown, so that a screw, such as the hex screw as shown in FIG. 10. It should be understood that virtually any available coupling may be provided between the axle and the member.  
         [0075]    [0075]FIG. 10 is a perspective view that illustrates a wheel assembly  520  that uses yet another embodiment for use in a heeling apparatus and includes a wheel  522  rotatably mounted to an axle  524  using a precision bearing  526 , and a first member  528  and a second member  530  coupled to each end of the axle  524  through a screw, such as hex screw  532 . The wheel assembly  520  is similar to wheel assembly  100 , which was described above in connection with FIG. 6, except that the wheel/axle assembly cannot be as easily inserted and removed.  
         [0076]    [0076]FIG. 11 is a side, partial cutaway view that illustrates one embodiment of a heeling apparatus  600  that illustrates a wheel assembly  602  provided in a sole  604  and an opening  606  in the sole  602  that does not extend completely through the sole  602 . As such, the mounting structure  608  may be provided or integrated into the sole  602  and may not be readily or easily removed. A wheel  610  is also shown extending partially below the bottom of the sole  602 , which provides the advantage of stealth heeling.  
         [0077]    [0077]FIG. 12 is a side view of another embodiment that illustrates a heeling apparatus  620  of the present invention with a removable wheel cover  622  positioned to cover a wheel  624  and an opening  626  in a sole  628 . The removable wheel cover  622  allows for the wheel to be provided in an extended position, i.e., below the bottom surface of the sole  628 , yet not engage a surface to roll. Although the heeling apparatus  620  of the present invention allows a user to walk and run, even with the wheel in an engaged position, the removable wheel cover  622  provides protection from dirt and debris and provides greater stability.  
         [0078]    In an alternative embodiment, a wheel stop, not expressly shown in FIG. 12, may be provided, in lieu of or in conjunction with the removable wheel cover  622 , to stop the rotation of the wheel  624 . In one embodiment, the wheel stop is made of virtually any material, such as a sponge or flexible material, that can be wedged between the wheel  624  and the opening  626  to stop or prevent the rotation of the wheel  624  and to stay in place through friction.  
         [0079]    In other embodiments of the wheel cover  622 , a wheel cover is provided when the wheel  624  has been removed from the heeling apparatus  620 . In a preferred embodiment, this wheel cover is generally flush with the remainder of the bottom of the sole  608 , and, hence, provides the function of a regular shoe when desired and protects the opening. This wheel cover may couple in any available manner, but preferably will couple to the wheel assembly in the same or similar manner that the wheel/axle assembly couples to the mounting structure. The removable wheel cover could clip or attach to the wheel assembly in many different ways.  
         [0080]    [0080]FIG. 13 is a bottom view that illustrates another embodiment of a heeling apparatus  700  with a spherical ball  702  serving as a wheel and positioned in a mounting structure  704  in an opening in the heel portion of the sole  706 .  
         [0081]    [0081]FIG. 14 is a perspective view that illustrates a “heeler”  800  using the present invention to “heel.” Heeling can be achieved using various techniques and, generally, requires a skill set of balance, positioning, flexibility, and coordination.  
         [0082]    An illustrative method for using a heeling apparatus on a surface may include running on a surface by using a forefoot portion of a sole of the heeling apparatus to contact the surface, and then rolling on the surface with a wheel of the heeling apparatus extended below the bottom of the sole through an opening in the sole by using a wheel of the heeling apparatus to contact the surface. Before running on a surface, the method may include walking on the surface while wearing the heeling apparatus with a wheel of the heeling apparatus extended below the bottom of a sole portion of the heeling apparatus before running on the surface. Heeling may also be performed on a hill or a surface that includes a decline.  
         [0083]    The method of heeling may also include engaging the wheel of the heeling apparatus to extend below the bottom of the sole portion of the heeling apparatus before walking on the surface. The method may also include walking on the surface while wearing the heeling apparatus before engaging the wheel of the heeling apparatus and with the wheel of the heeling apparatus retracted. Other variations on the method may include transitioning from rolling on the surface to either running, walking, or stopping on the surface by running on the surface through using the forefoot portion of the sole of the heeling apparatus to contact the surface just after rolling on the surface.  
         [0084]    The preferred position while heeling is illustrated by the heeler  800  in FIG. 14 where one heeling apparatus  802  is placed in front of the other heeling apparatus  804  while rolling on a surface. As can be seen from a back heel portion  806  of the heeling apparatus  804 , sometimes the clearance between the back heel portion  806  and the surface is small. As a result, in a preferred embodiment, the back heel portion  806  is made of a wear resistant material.  
         [0085]    The method of heeling may also implement any number of techniques for slowing or stopping. For example, rolling may be slowed by contacting the forefoot portion of the sole of the heeling apparatus to contact the surface to create friction and to remove the wheel from the surface. Another example includes slowing by contacting a heel portion of the sole of the heeling apparatus to contact the surface.  
         [0086]    [0086]FIG. 15 is a perspective view that illustrates a wheel  902  rotatably mounted to a collapsible axle  904 , which also may be referred to as a wheel/axle assembly  900 , similar to FIG. 4. The collapsible axle  904  may be implemented in any number of ways, such as an adjustable axle that is spring loaded, similar to what is shown in FIG. 16, or as a screw collapsible axle. This allows the wheel/axle assembly  900  to be more easily removable and/or retractable to a position where the wheel would not engage the ground if the wheel/axle assembly  900  where implemented in a heeling apparatus.  
         [0087]    [0087]FIG. 16 is a cutaway view that illustrates a collapsible axle  904  of the wheel/axle assembly  900  of FIG. 15 implemented as a spring loaded collapsible axle. As can be seen, the collapsible axle  904  may be adjusted or shortened by inwardly compressing both ends of the collapsible axle  904  to overcome the internal spring force.  
         [0088]    [0088]FIG. 17 is a perspective view that illustrates another mounting structure  920  for use with the wheel/axle assembly  900  and the collapsible axle  904 , as illustrated in FIG. 15 and FIG. 16, respectively, to form a wheel assembly. The collapsible axle  904  may couple to a first member  922  and a second member  924  at a first position  926  at the first member  922  and the second member  924  so that the wheel is in a retracted position. The collapsible axle  904  may also couple to the first member  922  and the second member  924  at a second position  928  so that the wheel is in an extended position.  
         [0089]    [0089]FIG. 18 is a side, cutaway view that illustrates a wheel assembly  940  positioned through an opening in a sole  942  that illustrates one embodiment of an axle  944  that couples to a mounting structure  946  to provide a retractable wheel  948  using an assembly that may be referred to as a king pin arrangement or dual king pin arrangement. This allows the retractable wheel  948  to be adjusted up or down, as desired, and from a retractable position to an extended position. A king pin  950  (which may be implemented as a threaded screw or bolt) is shown threadingly engaged in a threaded opening in a member of the mounting structure  946 . As the king pin  950  is screwed further into the opening in the member, the axle  944  is further retracted. A king pin  950  will also be provided at the other member to raise the other side of the axle  944 . In other embodiments, such as the mounting structure  500  in FIG. 9, a single king pin could be provided through the single member to provide retractable wheels through the coupling of the members and the axle.  
         [0090]    An example of a king pin type assembly is illustrated in U.S. Pat. No. 4,295,655, which is incorporated herein by reference for all purposes, issued to David L. Landay, et al., was filed on Jul. 18, 1979, was issued Oct. 20, 1981. This patent illustrates a king pin type assembly that could be implemented in an embodiment of the present invention.  
         [0091]    [0091]FIG. 19 is a bottom view that illustrates the wheel assembly  940  of FIG. 18 and further illustrates the dual king pin arrangement and the king pins  950  through the members of the mounting structure  946 .  
         [0092]    [0092]FIG. 20 is a side view that illustrates one member of the mounting structure  946  and further illustrates the coupling of the axle  944  to the mounting structure  946  using the dual king pin arrangement similar to FIG. 18. As discussed above, this allows the axle  944 , and hence the attached wheel, to be transitioned to any of a desired levels, and from a retracted position to an extended position.  
         [0093]    It should be understood that the axle may couple to a member of a mounting structure using any available technique and in virtually an unlimited number of ways. For example, an axle may couple to the first member and the second member of a mounting structure to move from a retracted position to an extended position through a spring arrangement. Similarly, an axle may couple to the first member and the second member of a mounting structure to move from a retracted position to an extended position through a hinged arrangement.  
         [0094]    Many other examples are possible, for example U.S. Pat. No. 3,983,643, which is incorporated herein by reference for all purposes, issued to Walter Schreyer, et al., was filed on May 23, 1975, was issued Oct. 5, 1976 illustrates a retractable mechanism that may implemented in one embodiment of the present invention. U.S. Pat. No. 5,785,327, which is incorporated herein by reference for all purposes, issued to Raymond J. Gallant, was filed on Jun. 20, 1997, issued on Jul. 28, 1998 illustrates simultaneously retractable wheels.  
         [0095]    [0095]FIG. 21 is a breakaway and perspective view that illustrates a two piece wheel  970  that includes an inner core  972 , an outer tire  974 , such as a urethane wheel, an axle  976  (which may not be shown to skill), and a bearing  978  that may be used in the present invention. In a preferred embodiment, the bearing  978  is small in comparison to the two piece wheel  970 , for example, the bearing  978  may have an outer diameter that is less than half the outer diameter of the outer tire  974 . This can provide significant advantages, that include a softer ride, better control, and are longer lasting. This is because the outer tire  974  can be larger and thicker. In other embodiments, the bearing  978  is larger and has an outer diameter that is more than half the outer diameter of the outer tire  974 . In a preferred embodiment, the inner core portion of the two piece wheel is made of a harder material that provides rigidity for enhanced bearing support, while the outer tire portion is made of a softer material, such as a soft urethane, for improved performance and a quieter ride. These types of wheels may be referred to as a “dual durometer” type wheel.  
         [0096]    Thus, it is apparent that there has been provided, in accordance with the present invention, a heeling apparatus and method that defines a new activity and sport that satisfies one or more of the advantages set forth above. Although the preferred embodiment has been described in detail, it should be understood that various changes, substitutions, and alterations can be made herein without departing from the scope of the present invention, even if all of the advantages identified above are not present. For example, the various embodiments shown in the drawings herein illustrate that the present invention may be implemented and embodied in a variety of different ways that still fall within the scope of the present invention. Also, the techniques, designs, elements, and methods described and illustrated in the preferred embodiment as discrete or separate may be combined or integrated with other techniques, designs, elements, or methods without departing from the scope of the present invention. For example, the wheel assembly may be removable or integrated into the sole of the footwear. Although the present invention has been primarily described with only one wheel positioned in the opening of the heel, the present invention certainly contemplates and covers multiple wheels positioned in the opening of the heel. Other examples of changes, substitutions, and alterations are readily ascertainable by one skilled in the art and could be made without departing from the spirit and scope of the present invention.