Patent Publication Number: US-7896364-B1

Title: Increased tilt roller wheel assembly

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     The subject matter contained herein claims priority from the commonly owned U.S. provisional patent application Ser. No. 60/928,016 filed on May 7, 2007, which is hereby incorporated by reference. 
    
    
     TECHNICAL FIELD 
     The presently disclosed invention relates most generally to roller wheel assemblies and structures for use with items such as skateboards, roller skates, etc. More particularly, the present invention relates to improved capability roller wheel assemblies, providing a simplified, strong, and highly tiltable arrangement, having increased and very fluid turning and steering capabilities. 
     BACKGROUND 
     This section provides a concise introduction to the available prior art, and associated motivations for a plurality of the presently disclosed features of the claimed invention. The art discussed herein is not to be considered admitted prior art, and is presented as a starting point to attempt to more clearly discuss and describe important features and structures of the roller wheel assembly of the present invention. 
     The prior art provides a number of examples of roller wheel assemblies, which are often termed “wheel trucks” or simply “trucks”. For example, a conventional skateboard is typically constructed using two trucks, with a first at the front end of a foot contacting board, and a second at the rear end. Importantly, due to several considerations, most commercial and stunt skateboards are intentionally structured with stiff and only slightly tiltable roller wheel assemblies (e.g., trucks). A first category of motivation for employing stiff (minimal tilting) trucks is related to stability and efficiency. That is, the use of stiff trucks results in a more stable and efficient forward motion, with more energy directed to forward rolling speed. In addition, when jumping and landing, as some skateboard users do, the stiffer trucks are helpful when elevating and safely landing. 
     A second issue that one encounters with most common skateboards, is the desire for a low riding construction, with the foot contacting member(s) relatively close to the ground. As a result, if the trucks of these skateboards were relaxed (e.g., not as stiff, and more tiltable), the tops of the roller wheels would likely contact a bottom surface of the foot contacting (top) member, typically a somewhat flattened board or board-like construction. 
     Importantly, and as understood by skilled persons, the available and known stiff roller wheels assemblies of the prior art clearly, and by design, result in an inability of an individual to utilize certain body motions for causing a somewhat sharp zigzagging. With the user as an energy source, such zigzagging motions may be employed to ‘propel’ the skateboard along a ground surface that is level or having a modest incline. In contrast, when a typical individual is observed using a conventional (stiff) skateboard, and the individual comes to any type of inclined grade, they will often employ an arrangement wherein one foot is left on the top surface of the skateboard while the individual&#39;s second foot is employed for repeatedly contacting and pushing off on a ground surface, thereby propelling the skateboard up the grade. This pushing-off activity is employed at regular intervals, until enough speed is attained, or alternately a level or downhill grade is encountered. 
     When considering the present invention, and in contrast to the known prior art, when roller wheel assemblies are employed that are specifically structured for a greater tilting (e.g., up to 40 to 50 degrees), an individual may employ a self-propelling zigzagging activity. As will be seen, the provided increased tilting capability (say up to 40 degrees), and its inherent easy and fluid motion, enables the required tighter, sharper, and rapidly alterable turning capability needed for such zigzagging. This may be termed an “enhanced tilting and steering capability”, in accordance with the invention. When observed in use, the enhanced, increased, and readily controllable tilting and steering, leads to an activity that is more akin to snowboarding, than it is to skateboarding. This is due to the significantly increased back and forth (zigzagging) motion that is employable during use. This fully supported back and forth propulsion method is also an excellent form of aerobic exercise. 
     The prior art does provide examples of more tiltable roller wheel assemblies. However, those found have inadequate structures that are not practical for long term, heavy duty use. In addition, these known arrangements and structures are substantially fixed, lacking the configurable and adjustable features of the present invention. Accordingly, these structures may be adequate for children&#39;s devices and light duty usage, but are not durable and capable of heavy practical use, say by teenagers and fully grown individuals. 
     As such, and as appreciated by skilled persons, there is a need to provide improved and more durable roller wheel assemblies that are simple in structure, and arranged to enable ready and increased tilting, and (thereby) enhanced steering, turning, and zigzagging capabilities, while also providing a very strong, long life, and easy to manufacture structure. A number of other characteristics, advantages, and or associated novel features of the present invention, will become clear from the description and figures provided herein. Attention is called to the fact, however, that the drawings are illustrative only. In particular, the embodiments included and described, have been chosen in order to best explain the principles, features, and characteristics of the invention, and its practical application, to thereby enable skilled persons to best utilize the invention and a wide variety of embodiments providable that are based on these principles, features, and characteristics. Accordingly, all equivalent variations possible are contemplated as being part of the invention, limited only by the scope of the appended claims. 
     SUMMARY OF PREFERRED EMBODIMENTS 
     In accordance with the present invention, a roller wheel assembly is comprised of a simple, durable, and easily serviced construction, which provides ready and easy tilting. Even when structures are provided for a light biasing of the assembly to a centered and substantially straight rolling position, the structures of the invention clearly support an increased steering and turning capability—especially when compared to common roller wheel assemblies such as found on the well known and ubiquitous single-board dual-truck skateboards. Preferred embodiments of the presently taught roller wheel assemblies of the invention include a support member, a rotatable coupling that is preferably bearing-based, and a wheeled support structure having two rollably coupled, spaced and axially aligned roller wheels. 
     The support member includes a first upper portion, which may actually be fastened to, or integrated into, other included structures, such as a flattened center member proving a top foot contacting area. The support member also includes a second downwardly angled portion. The downwardly angled portion is preferably considerably thinner than it is wide, preferably forming a plane or surface, and is provided having a through-bore. Importantly, a preferred ‘downward angle’ of the downwardly angled portion of the support member, with respect to a providable first upper portion, may be understood to be in the range of 30 degrees to 60 degrees. Other more preferred ranges and selected angles will be discussed hereinafter. 
     The roller wheel assembly further includes a roller wheel support structure having at least two roller wheels rollably coupled thereto. Preferred roller wheel support structures will include a substantially transverse wall portion or member, and at least two spaced side walls. Each side wall is substantially orthogonally and rigidly coupled proximate to one of the ends of the transverse wall. Accordingly, the preferred roller wheel support structure may be provided as a 3-walled somewhat U-shaped structure, or more preferably as a very rigid easy to manufacture 4-walled rectangular structure, as will be depicted in the figures and discussed in the detailed description. The roller wheel support structure may be cast, machined, and or formed by bending and or cutting raw materials (e.g., plates, sheets, rectangular conduits/tubings, etc.). 
     The transverse wall of the roller wheel support structure also includes a bore (hole) located proximate to a center location. The bore of the transverse wall is preferably provided as a threaded hole. The threaded hole is employed, along with the through-bore of the downwardly angled portion, as a portion of a steering related bearing-based rotatable coupling. It may be noted that the threaded hole may equivalently be termed a ‘threaded-bore’. Preferred embodiments of the bearing-based rotatable coupling may include one or more axially aligned bearings, as is depicted in the figures. In a most preferred arrangement, at least two axially aligned bearings are included with each bearing located on an opposing side of the preferably flattened downwardly angled portion of the support member (and axially aligned with the above discussed threaded-bore and through-bore). An axis of rotation for the bearing-based rotatable coupling is established by a capped center shaft that passes through each bore, a center of each included bearing, and is capped at each end of the included center shaft. The center shaft, which may be provided by a basic threaded bolt, establishes what may be termed a “steering related axis of rotation of the bearing-based rotatable coupling”. 
     As may be understood by skilled persons, the use of a rotatable coupling for coupling the downwardly angled portion of the support member to the roller wheel support structures, which are taught herein, yields a structure and arrangement such that a side-to-side tilting of the upper portion of the support member, with respect to a ground surface, provides ready and easily effected steering and a sharp turning capability. For example, the present invention&#39;s structure will support motion such as sharp zigzagging (equivalent to a motion used in snowboarding), and a rapid tacking back and forth. The increased and very smooth tilting provides for the enhanced steering capability of the invention. The term enhanced tilting and steering capability is to be understood to include a tilting capability wherein the upper portion of the support portion (e.g.,  FIGS. 6B and 6C ) is tilted upwards of 45 degrees, +/−5 to 10 degrees, or so. Importantly, the present structure of the invention supports such tilting, resulting in very sharp turning, with typical minimal turning radius of 1 to 2 feet (with max tilting), while keeping all included roller wheels firmly contacting the ground. The traction provided by the present roller wheel assembly, when considering the enhanced tilting and steering capabilities, is notable. 
     Most preferred roller wheel support structures will be provided for establishing a common or effective rolling axle or axis for each included pair of spaced roller wheels. Examples of simple arrangements will be provided wherein a roller wheel may be fixed to a side wall of the roller wheel support structure in an adjustable fashion. Further, a most preferred bearing-based rotatable coupling of the invention will enable a user to selectably rotate, by 180 degrees, the roller wheel support structure, for placing the roller wheel assembly in one of either a first low rolling position or a second high rolling position. The first low rolling position provides for a lower and more stable operation—best used for new/unskilled users. The second high rolling position raises each included support member, along with structures coupled or fixed to the upper support portion. 
     Another novel feature of the present roller wheel assembly includes an adjustment arrangement wherein the rolling axis of paired roller wheels may be adjusted. For example, one contemplated arrangement provides for a plurality of spaced and preferably substantially aligned mounting holes being provided upon the side walls of the roller wheel support structure. Further, the adjusting will move the rolling axis either up and down (upon the side walls), or forward and back, based on whether the roller wheel support structure is in the first low rolling position or the second high rolling position. A most preferred adjustment structure provides for a series of spaced and threaded holes to be provided. The threaded holes may be substantially aligned (as depicted) or provided in a more staggered pattern. 
     It is contemplated that the roller wheel assembly of the invention may most preferably be provided in at least pairs, with one roller wheel assembly provided proximate to end locations of what may be termed a “roller wheel platform”. Accordingly, by way of a number of arrangements (as will be fully discussed), the upper support portions of included roller wheel assemblies will be substantially rigidly coupled in an opposing (180 degree rotated) mounting arrangement. This rigid coupling may be provided in many forms, including bolted ( FIG. 1 ), welded, monolithic (1-piece) structures ( FIG. 4 ), and fully integrated monolithic ( FIG. 11 ). 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings, like elements are assigned like reference numerals. The drawings are not necessarily to scale, with the emphasis instead placed upon the principles and features of the present invention. Additionally, each of the embodiments depicted are but one of a number of possible arrangements utilizing the fundamental concepts of the present invention. The drawings are briefly described as follows: 
         FIG. 1  depicts an elevated perspective view of a first single-ended embodiment of a roller wheel assembly in accordance with the present invention. 
         FIG. 2  provides a side view of a roller wheel assembly that is consistent with the embodiment of  FIG. 1 , and provides additional details of a steering-related bearing-based coupling and a roller wheel support structure, which readily enables increased tilting and steering. 
         FIG. 3  is an enlarged, partially cut-away, and possibly expanded side view of a downwardly angled (support) portion structured with at least one friction reducing bearing-pair and an associated steering related center shaft, which are portions of a bearing-based rotatable coupling. 
         FIG. 4  provides a side view illustrating a pair of opposing and coupled roller wheel assemblies joined by a middle or center coupling portion, and forming what may be termed a roller wheel platform, useful for having affixed thereto foot or feet engaging structures such as a board or suitably flattened surfaces (see  FIG. 8 ), a foot securing boot (see  FIGS. 9A-9B ), and other possible and providable foot or feet engaging structures. 
         FIG. 5 . provides a conceptual high level block diagram of a roller wheel platform of the invention, employing two roller wheel assemblies, with each consistent with the depictions of  FIGS. 1 through 4 . 
         FIGS. 6A ,  6 B, and  6 C depict conceptual embodiments of the invention with double ended roller wheel assemblies coupled by a center coupling portion, shown oriented level for substantially straight-line motion ( FIG. 6A ), or oriented tilted left for causing motion/movement to the left ( FIG. 6B ), or oriented tilted right causing motion/movement to the right ( FIG. 6C ), wherein an actual magnitude of the turning motion produced determined by the tilt angle applied to the center coupling portion. 
         FIGS. 7A and 7B  show an embodiment of the invention that is consistent with the roller wheel assembly of  FIG. 4 , which has been re-configured with the roller wheel assemblies rotated 180 degrees, placing the center coupling portion, the second support portion, and downwardly angled support portions of each roller wheel assembly in an ‘elevated position’.  FIG. 7B  also additionally illustrates the even greater steerability of the roller wheel assemblies of the invention in this ‘high-riding’ or ‘high-rolling’ configuration. 
         FIG. 7C  illustrates yet another operating configuration where only one of the two roller wheel assemblies has been rotated 180 degrees, providing a tilted and possibly more challenging and difficult operating configuration, or one useful on long downhill or uphill stretches. 
         FIG. 8  illustrates an embodiment of a roller wheel board structured using the roller wheel assemblies of the invention, depicted including two separate foot supporting boards or foot contacting pads. 
         FIGS. 9A and 9B  provide a depiction of roller wheel assemblies of the invention employed in a booted roller skate configuration. 
         FIG. 10  provides an enlarged view of a rear friction brake structure that is employable with the depicted embodiments of the invention, explicitly depicted with the embodiment of  FIGS. 9A and 9B . 
         FIG. 11  provides a perspective underside view of one possible modified embodiment of the present invention, which is shown having downwardly angled (support) portions that are formed using opposing downwardly angled portions provided from a curved cut (U-shaped as depicted) made in a bendable and preferably plate material. 
     
    
    
     
       
         
           
               
             
               
                   
               
               
                 Partial List Of Reference Numerals 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
            
               
                   
                 20 
                 roller wheel assembly 
               
               
                   
                 20a 
                 a first roller wheel assembly 
               
               
                   
                 20b 
                 a second roller wheel assembly 
               
               
                   
                 22 
                 support member 
               
               
                   
                 22a 
                 first upper portion of 22 
               
               
                   
                 22aa 
                 mounting holes 
               
               
                   
                 22b 
                 second downwardly angled portion of 22 
               
               
                   
                 22bb 
                 end portion of 22b 
               
               
                   
                 23 
                 through-bore 
               
               
                   
                 24 
                 bearing seat (fixed spacer) 
               
               
                   
                 26a, 26b 
                 (opposing) counter bores 
               
               
                   
                 28 
                 (tilt or steering) stop post 
               
               
                   
                 30 
                 roller wheel 
               
               
                   
                 32 
                 axle bolt of 30 
               
               
                   
                 32a 
                 axle bolt head of 32 
               
               
                   
                 32b 
                 threaded end of 32 
               
               
                   
                 34 
                 bias return spring 
               
               
                   
                 34a 
                 first end of 34 
               
               
                   
                 34b 
                 second end of 34 
               
               
                   
                 36 
                 fixing bolt of 34 
               
               
                   
                 40 
                 bearing-based rotatable coupling 
               
               
                   
                 42 
                 bolt 
               
               
                   
                 42a 
                 bolt head 
               
               
                   
                 42b 
                 bolt end 
               
               
                   
                 44 
                 securing nut 
               
               
                   
                 46 
                 spacer 
               
               
                   
                 48 
                 bearing 
               
               
                   
                 50 
                 roller wheel support structure 
               
               
                   
                 50a 
                 first transverse wall of 50 
               
               
                   
                 50b 
                 side wall of 50 
               
               
                   
                 50c 
                 (optional) second transverse wall 
               
               
                   
                 51a, 51b, 51c 
                 mounting holes in 50b 
               
               
                   
                 53 
                 threaded-bore 
               
               
                   
                 58b 
                 second steering stop post 
               
               
                   
                 60 
                 friction brake 
               
               
                   
                 62 
                 ground contacting braking portion 
               
               
                   
                 66 
                 brake mounting bracket 
               
               
                   
                 66a 
                 first bracket portion 
               
               
                   
                 66b 
                 second bracket portion 
               
               
                   
                 70 
                 (center) coupling or coupling structure 
               
               
                   
                 80 
                 roller wheel platform (simple) 
               
               
                   
                 80a 
                 first or front end of 80 
               
               
                   
                 80b 
                 second or rear end of 80 
               
               
                   
                 90 
                 foot contacting member 
               
               
                   
                 90-1 
                 boot embodiment 
               
               
                   
                 100 
                 ground surface 
               
               
                   
                 A 
                 downward angle 
               
               
                   
                 R 
                 (steering) axle or axis of rotation 
               
               
                   
                 P 
                 plane passing through 22b 
               
               
                   
               
            
           
         
       
     
     DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION 
     It is important to establish the definition of a number of descriptive terms and expressions that will be used throughout this disclosure. The term ‘enhanced tilting and steering capability’ is to be understood to include a tilting capability wherein the upper portion of the support portion (see  FIGS. 6B and 6C ) has tilting capability, based on the specific embodiment, in a preferred range of 40 to 50 degrees. The term ‘tilting’ may be understood to mean or indicate that one side or edge of included upper portions of the support member is higher or above an opposite side or edge. A most preferred range would support tilting (to either side) of 40 to 50 degrees. A most preferred tilting angle would be substantially 45 degrees. Importantly, the present structure of the invention supports these ranges of tilting, resulting in a very sharp and controlled turning capability. Specifically, the embodiment of the present roller wheel assembly will readily support a typical minimal turning radius of 1 to 2 feet (realized by employing a maximum or near maximum tilting angle). It may also be noted that the enhanced tilting and steering capability of the present invention permits such steep tilting angles, while fully maintaining all (pairs of) roller wheels in firm contact with the ground surface upon which the roller wheel assembly or assemblies of the invention are in rolling contact. This results in increased traction not readily seen with the common and ubiquitous skateboards commonly in use today. The term ‘substantially’ will be employed as a modifier to indicate exactly or close to the given feature, structure, or characteristic. For example, the phrase ‘a tilting angle of substantially 45 degrees’ may indicate the tilting angle is exactly 45 degrees or equivalently close to 45 degree (e.g., +/−degrees from true/exact 45 degrees). Similarly, the term ‘substantially parallel’ as employed herein will describe a relationship wherein two members, items, or portions may be exactly parallel, or alternately somewhat close to parallel. As such, substantially parallel items may actually be up to +/−5 to degrees or so from a truly parallel arrangement, and still be correctly considered ‘substantially parallel’ within the present disclosure. As such, the terms ‘substantially parallel’ and ‘roughly parallel’ may be considered equivalents. In like fashion, the terms ‘substantially orthogonal’, ‘substantially orthogonally oriented’, etc., can be assumed to mean that the members may be exactly fixed or rigidly coupled to each other at a true 90 degree angle, or alternately somewhat close to 90 degrees. As such, substantially orthogonal members may actually be up to +/−5 to 10 degrees or so from a truly orthogonal arrangement, and still be correctly termed substantially orthogonal. 
     Continuing, the terms ‘coupler’, ‘coupled to’, ‘coupling’, etc., are to be understood to mean that two or more described items are either directly connected together, or alternately, connected to each other via one or more additional, possibly implied or inherent structures or components. For example, when considering the rollable coupling of a roller wheel to a roller wheel support structure, various mechanical components may be included, such as bolts, nuts, locking structures such as cotter pins, locking pins, etc., which may not be explicitly discussed in any significant detail—as these items are well understood by skilled persons. The term ‘downwardly angled’ as employed when describing and discussing the relationship of the downwardly angled portion of the support member with respect to the upper support portion, is intended to mean that a sharp or possibly gradual angle is provided, causing a downward angling in a possibly preferred range of 30 to 60 degrees. A possibly most preferred downward angle, say of 45 degrees, will therefore indicate that the angle between a plane or surface associated with the upper support portion (of the support member) and a plane or surface of the downwardly angled portion may most preferably be substantially 45 degrees. Other important terms and definitions will be provided, as they are needed, to properly define the present invention and its associated novel characteristics and features. In addition, the terms and expressions employed herein have been selected in an attempt to provide a full and complete description of the invention. These terms may very well have equivalents known to skilled individuals, which may be long established in the art. As such, the terminology employed has been carefully chosen and is intended for illustration and completeness of description, and may very well have equivalents that are known in the art, but not employed here. 
     Referring now to the drawings,  FIGS. 1 and 2  provide illustrations in the form of an elevated perspective view and a profile/side view, respectively, of a first single-ended embodiment of a roller wheel assembly in accordance with the present invention. As depicted, the roller wheel assembly  20  includes a support member  22 , which may be provided as a simple bracket. The support member  22  may include a first upper portion  22   a  and a second downwardly angled portion  22   b . When provided as an angled bracket, the first upper portion  22   a  may have a length as depicted in  FIG. 1 . As illustrated, and best seen in  FIGS. 7A through 8 , the first upper portion  22   a  may be structured for enabling a coupling of the roller wheel assembly to an includable foot contacting top member. For example, as clearly seen in  FIGS. 1 and 2 , mounting holes  22   aa  may be included to enable a foot contacting member (e.g., a top board) to be fastened to each included roller wheel assembly  20 . It may be noted that contemplated includable foot contacting (top) members may be provided as flattened plate-like or board-like structures formed of one or more materials, such as wood, plastic, metal, composites, laminates, etc. 
     Also shown in  FIGS. 1 and 2 , and possibly best seen in  FIG. 3 , the downwardly angled portion  22   b  of the support member  22  includes a through-bore  23 . The through-bore  23  is included for mechanically establishing a rotational axis of a bearing-based rotatable coupling  40 , which is a steering related structure. Importantly, the inclusion of the through-bore  23  in the downwardly angled portion  22   b  establishes an angle for the rotational axis of the bearing-based rotatable coupling  40  of the invention, which is directly related to the downward angle (of the downwardly angled portion  22   b ). This angled arrangement aids in establishing the enhanced side-to-side tilting/steering capability of the first upper portion  22   a , with respect to a ground surface  100 . The ground surface  100  may be provided by any smooth hard surface, including those made of concrete, asphalt, wood, decking material, etc. 
     It may be noted, as depicted in the figures include herewith, the downwardly angled portion may preferably be considerably thinner than it is wide. For example, a preferred downwardly angled portion  22   b  may be provided by a flattened member, preferably forming or having a plane P passing therethrough. For example, as depicted in  FIG. 2 , the plane P is shown from an end or side view (with the plane thereby viewable in only two dimensions). 
     Returning again to  FIGS. 1 through 3 , a roller wheel support structure  50  is shown rotatably coupled to the downwardly angled portion  22   b  of the support member  22 , by way of the bearing-based rotatable coupling  40 . The roller wheel support structure  50  preferably includes a first transverse wall  50   a , and two spaced side walls  50   b , which may be fixed or formed so as to be substantially orthogonal to the first transverse wall  50   a . For example, as depicted a first end of each side wall  50   b  may be fixed to the first transverse wall  50   a  one of the opposite end locations of the first transverse wall  50   a . That is, the first end of a first side wall  50   b  is fixed to a first end of the transverse wall  50   a , while the first end of a second side wall  50   b  is fixed to a second end of the first transverse wall  50   a . When so configured the roller wheel support structure  50  may be substantially U-shaped. However, other useful shapes and arrangements are possible. For example, as clearly illustrated in  FIGS. 1 through 3 , a second transverse wall  50   c  may be provided that is arranged substantially parallel to, and spaced from, the first transverse wall  50   a . Accordingly, the roller wheel support structure  50 , as depicted, may be provided as possibly more rigid 4-walled somewhat rectangular structure. 
     Regardless of whether the roller wheel support structure  50  is provided as a substantially U-shaped arrangement, a rectangular 4-walled construction, or another equivalent structure, the inclusion of an adjustment means may be provided in preferred embodiments that enables each of the roller wheels  30  to be adjustably fixed to the roller wheel support structure, as determined by the user. For example, as shown in  FIGS. 1 and 2 , a plurality of spaced and possibly substantially aligned mounting holes, designated  51   a ,  51   b , and  51   c  (for the embodiments illustrated) may be provided. The spaced mounting holes are preferably located upon the side walls  50   b  of the roller wheel support structure  50 . The mounting holes may also be termed roller wheel ‘axle receptacles’ or ‘axle bolt receptacles’, and in a simple embodiment are provided by threaded holes passing through the side walls  50   b  of the roller wheel support structure  50 . Clearly, the depicted spaced mounting holes  51   a ,  51   b , and  51   c , enable and support a front-to-back adjustment capability. For example, as shown in  FIG. 1 , an included mounting or axle bolt  32  is shown threaded into mounting hole  51   a —with the end  32   b  shown extending from the opposite side of hole  51   a  of  FIG. 1 . Therefore a rolling axis (or effective axle) for each roller wheel of  FIG. 1  may be arranged for accepting an axle bolt  32  into mounting hole  51   a . Alternately, as implied in  FIG. 2 , the rolling axis of the roller wheels  30  may be moved (back) when mounted (screwed) in mounting holes  51   b . This simple arrangement of a plurality of spaced and possibly aligned mounting holes enables a simple adjusting of the mounting locations and the rolling axis of included roller wheels  30 . 
     As best seen in  FIG. 3 , one possibly preferred bearing-based rotatable coupling  40  of the roller wheel assembly  20  may include at least two axially aligned bearings  48 . The bearings  48  are most preferably located on an opposing side of the flattened downwardly angled portion  22   b  of the support member  22 . As depicted, in a most preferred embodiment each bearing  48  is seated within an opposing counter bore  26   a  and  26   b , respectively. That is, a first counter bore  26   a  is provided on a first side of the downwardly angled portion  22   b , while a second counter bore  26   b  is provided on a second side of the downwardly angled portion  22   b . Importantly, the depth of the counter bores  26   a  and  26   b  are such that they collectively form (or leave) a bearing seat  24 . The bearing seat  24 , which is integral to the downwardly angled portion  22   b  as shown, acts as a seat and support surface for one side of each included bearing  48 . 
     It may be noted that in order to properly seat and support each included bearing  48 , the size, depth, etc., of the opposing counter bores will be provided an inner diameter establishing the opening of the through-bore  23  that is both greater than the diameter of the (center shaft) bolt  42  passing there-through, while also being less than the diameter of the counter bore—so as to suitably establish the bearing seat  24 . For example, as illustrated in  FIG. 3 , the depth of the counter bores  26   a  and  26   b  may be substantially equal to the thickness of the bearing seat  24 , or somewhat deeper than depicted. 
     As shown in  FIG. 3 , and also depicted in  FIGS. 1 and 2 , the bearing-based rotatable coupling  40  includes a center shaft. A preferred and simple capped center shaft may be provided by a fully threaded bolt  42  and a mating nut  44 . The bolt  42  preferably is threaded into a threaded-bore  53  located proximate to a center location of the transverse wall  50   a . Once threaded into the threaded-bore  53 , and preferably tightened snugly thereto, the extending shaft portion of the bolt may have placed over it, or upon it, a spacer  46  and the first bearing  48 . The shaft is then placed into and through the through-bore  23 , causing a seating of this first bearing within the counter bore  26   b , and an extending of the bolt end  42   b  out of the through-bore  23 . Next, the second bearing  48  is placed over the bolt  42 , followed by a second (upper) spacer  46 , and then capped by securing nut  44 . See  FIGS. 1 to 3 . It may be noted that nut  44  is preferably a self locking nut that may be tightened to a snug and very lightly loading tightness (so as to not damage the bearings  48 ). Once the arrangement of  FIG. 3  is fully assembled, as shown in  FIGS. 1 ,  2 , and  4 , the tilting of the upper support portion  22   a  with respect to ground surface is free and easy, with very low tilting friction resulting from the bearing-based rotatable coupling  40  and the rollable mounting of the roller wheels  30 —which will also preferably include friction reducing roller bearings. 
     It is important to note that the downward angle of the downwardly angled portion  22   b , directly affects the downward angle of the center shaft (bolt  42 ) and the associated steering related rotational axis of the bearing-based rotatable coupling  40 . As understood by skilled persons, the downward angle A of  FIG. 2  represents a complementary angle of the angle of the shaft of the bolt  42 . That is, due to the substantially orthogonal mounting of the bolt  42  with respect to both the transverse wall  50   a  and the downwardly angled portion  22   b , the downward angle A and the angle of the shaft of the bolt when added are therefore substantially 90 degrees (or complementary). As such, if angle A is selected to be 45 degrees, the angle of the center shaft (e.g., of bolt  42 ) is also 45 degrees. If angle A is substantially 60 degrees, then the center shaft of the bearing-based rotatable coupling  40  is mounted at an angle of substantially 30 degrees. A possibly preferred angle A of the downwardly angled portion  22   b  may be provided in the range of 30 to 60 degrees. A more preferred range for angle A would be 40 to 50 degrees. While a most preferred angle A would typically be substantially 45 degrees. Further, the downward angle A of the downwardly angled portion  22   b  may be assumed to be measured with respect to at least one of the first upper portion  22   a  of the support member  22  or with respect to the ground surface  100  upon which the roller wheel assembly  20  rolls. 
     Turning now to  FIG. 4 , an embodiment of a roller wheel platform  80  in accordance with the present invention is illustrated in an elevated side view depiction. The roller wheel platform  80  may be formed of two opposing roller wheel assemblies  20  that are coupled by a center coupling  70 . This arrangement is also depicted in the conceptualized block diagram of  FIG. 5 . As illustrated in both  FIGS. 4 and 5 , the center coupling  70 , the upper support portions  22   a , and the downwardly angled portions  22   b  are each formed of a single monolithic strip of material having two ‘end proximate’ bends. Alternately, the upper support portions  22   a  may be fastened or fixed to a discrete center support and coupling portion (not explicitly shown), say using a plurality of included mounting holes  22   aa  (of  FIGS. 1 and 2 ). 
     As conceptually depicted in  FIG. 5 , regardless of how a first roller wheel assembly  20   a  is coupled to the opposing or second roller wheel assembly  20   b , the integral bearing-based rotatable couplings  40  supports and enables the tilting of the upper support portions  22   a  (and coupling  70 ) for a very smooth and controlled steering of the roller wheel platform  80 . As depicted in  FIGS. 6A ,  6 B, and  6 C, a user may control the steering of the roller wheel platform  80  by controlling the tilting or tilt angle of the center coupling  70  (and upper support portions  22   a  fixed thereto). Specifically, if substantially straight line motion is desired a user would attempt to maintain the upper portions  22   a  and any included coupling  70  level, as shown in  FIG. 6A . If an individual wants to turn left, the first upper portions  22   a  and coupling  70  would be tilted left, with the left edge of  70  lower than the right edge (as depicted in  FIG. 6B ). Note that the tilting and associated steering is quite effective as both the front roller wheel assembly and the rear roller wheel assembly each contribute to the turning action. Similarly, if a user wants to turn right, the coupling  70  is tilted right (the right edge lower than the left edge), causing motion/movement to the right (see  FIGS. 6C and 7B ). Clearly a slight tilting will cause a more gradual turn, while a sharp angled tilting will cause a much sharper turn. Therefore, the actual magnitude of the turning motion produced may be generally considered proportional to and substantially determined by a tilt angle applied to the upper portions and or a center coupling portion, or possibly more correctly by a plane established by these members. For example, a more controlled tilting may be effected fastening one large top foot contacting member  90 , as illustrated in  FIGS. 7A and 7B . The adding of a one piece top member ( FIG. 7A ), or separate smaller foot contacting members ( FIG. 8 ), yields an increase in width and area for the contacting of an individual&#39;s feet, and directly leads to a more controllable ride. 
     Returning briefly to  FIGS. 2 ,  7 A and  7 B, yet another feature of the present roller wheel assembly of the invention will be discussed. As can be seen by contrasting  FIG. 2  with  FIG. 7A , the bearing-based rotatable coupling  40  and the roller wheel support structure  50  are each structured such that the roller wheel support structure  50  may be rotated 180 degrees. Accordingly, as seen in  FIG. 2  a roller wheel assembly  20  may be operated in what may be termed a first ‘low rolling position’, or equivalently a low riding position. This first (low) rolling position is shown in  FIGS. 1 ,  2 , and  4 . When in the low rolling position, an included plurality of spaced and substantially aligned mounting holes are arranged to be substantially horizontally spaced—thereby enabling an adjusting of the roller wheel rolling axis/locations in a forward and backward manner, which is equivalent to a front-to-back adjustment capability. 
     Similarly, and as depicted in  FIGS. 7A ,  7 B, and  7 C, the roller wheel support structure  50  may be rotated 180 degrees about the rotational axis of the bearing-based rotatable coupling  40 , placing the roller wheel assembly  20  into a second ‘high rolling position’, which is also a high riding position. As shown, when in the high rolling position of  FIGS. 7A and 7B , the center coupling  70  is now more elevated above the ground surface  100 , and the plurality of spaced and substantially aligned mounting holes are now arranged to be substantially vertically spaced, thereby enabling an adjusting of the roller wheel locations in an up and down manner. As possibly understood by skilled persons, there will be an additional degree of difficulty experienced by a user when the roller wheel support structures  50  are each in the second high rolling position. As such, the lowering of the roller wheel assemblies, and the associated roller wheel platform  80 , may result in an easier ride with the roller wheels  30  mounted in the mounting holes  51   a  (the front/top most mounting hole). It may be further noted that when in the second high rolling position, a possibly increased tilt angle may be achieved, yielding an even more increased steering and turning ability. 
     When considering the stability and the clearly enhanced tilting and steering capability of the present roller wheel assemblies of the invention, the steering related axis of rotation ‘R’, of the bearing-based rotatable coupling  40 , which is clearly shown in  FIG. 3 , is downwardly angled at a preferred downward angle of 45 degrees (as shown in  FIGS. 2 and 3 ). In addition, due to the structure and configuration of each included roller wheel support structure  50 , if a mounting hole such as  51   c  is employed, the rolling axis of each roller wheel may be offset or displaced considerably from the plane of the downwardly angled portion  22   b . More specifically, the roller wheel support structures  50  enable the rolling axis of the roller wheels to be adjusted so that: 
     a) when in the low rolling position, the wheelbase of the roller wheel platform may be adjusted and altered, enabling an adjusting of the turning radius and steering responsiveness of a roller wheel platform  80 ; and 
     b) when in the high rolling position, the height of an includable foot contacting member  90  may be altered, possibly altering the difficulty of use and the maximum level of tilt/steering available. 
     Turning to  FIG. 7C , depicted is a roller wheel platform  80  having a first (left) roller wheel assembly  20   a  with the roller wheel support structure  50  configured in the high rolling position, while the second (right) roller wheel assembly  20   b  is arranged with its roller wheel support structure  50  in the low rolling position. The configuration of  FIG. 7C , where only one of the two roller wheel assemblies has been rotated 180 degrees, provides a tilted and possibly more challenging and difficult operating configuration. Also, such a mixed configuration may be useful on long downhill stretches, or long uphill stretches. 
     As seen in  FIGS. 1 and 4 , a bias return spring  34  may be included with preferred embodiments of the roller wheel assembly  20  of the invention. As depicted, the illustrated embodiments include a bias return spring  34  having a first end  34   a  and a second end  34   b . Each end  34   a  and  34   b  are further depicted as being fastened, in a somewhat flexible or rotatable fashion using small fixing bolts  36 . The bias return spring  34  may be mounted with the first end  34   a  of the bias return spring  34  coupled to the support member  22  and a second end  34   b  of the bias return spring  34  coupled to the transverse wall  50   a  (see  FIG. 1 ). This and equivalent mounting arrangements may be chosen so that the included bias return spring  34  effects a biasing and an aiding in returning the roller wheel support structure  50  to a straight steering position—as depicted in  FIGS. 1 and 6A . Equivalently, the bias return springs  34  aid in returning the first upper (support) portions  22   a  to a level and substantially straight steering/rolling position. 
     Yet another feature of the embodiments of the roller wheel assemblies  20  of the invention is best seen in  FIG. 11 , as shown a pair of tilt limiting stop posts  28  may be included. Each included stop post  28  may be provided, as shown, by a simple and possibly stubby projection extending outwardly from a read surface of the downwardly angled portion  22   b . For example, in a most simple arrangement a common threaded screw, possibly with a protective nut or sleeve (not shown) covering the threads. The function of the stop post  28  is to simply limit the tilting of included foot contacting upper portions (e.g., center coupling  70  and a foot contacting member fixed, fastened, or formed therewith), so that the outer rolling surface of the roller wheels  30  does not contact and rub against an under surface of any of these members (at maximum tilting). For example, the stop posts  28  of  FIG. 11  are included to prevent the roller wheels  30  from rubbing up against an undersurface of the modified foot contacting member  90 - 2 . 
     As appreciated by skilled individuals, when features such as the bias return spring  34  of  FIG. 1  and the stop posts  28  of  FIG. 11  are included, it may be necessary to loosen or remove one of the small fixing bolts  36  and or to back out one or more stop posts  28 , to properly effect the 180 degree rotating of the roller wheel support structure  50  (for causing a change from one of the high or low rolling positions). 
     It must be understood, that the upper support portions  22   a  and included center coupling portions/members of the roller wheel platforms  80  of the invention may be realized using a number of possible approaches and structures. Several are illustrated herein, and will be concisely summarized below. Certainly, other arrangements are possible and providable by skilled persons that have carefully reviewed this disclose. As illustrated in  FIG. 2  (implied) and  FIG. 4  (explicit) the upper support portion  22   a  may extend and transition into the center coupling  70 . Clearly, the fastening (e.g., screwing or bolting) of each included upper support portion  22   a  to a center flattened strip/bar portion is also possible. For example, the embodiment depicted in  FIG. 8 , may provide for shortened upper support portions  22   a  (blocked from view) that are bolted to each included (octagonal) foot contacting member  90 , along with each end of an included center coupling  70 . Alternately, the implied shortened upper support portions  22   a  may simply be securely fastened to a common skateboard-type top board (not explicitly shown). 
     Yet another possible configuration for providing the upper support portions  22   a  of the support members  22 , which is truly monolithic in nature, is illustrated in  FIG. 11 . Illustrated therein is a first end  90 - 2   a  of a flattened and elongated foot contacting member  90 - 2 , which may be provided having a somewhat traditionally shaped rounded or elliptical plate material. As shown, the foot contacting member  90 - 2  includes a curved cut provided for enabling a portion of the plate material proximate to (and within) the curved cut to be bent downwardly. This downward angled portion is bent and or fixed at a selected downward angle (e.g. downward angle ‘A’), which is most preferably substantially 45 degrees. As such, and as implied by  FIG. 11 , the curved cut may be substantially U-shaped (as depicted), (preferably soft) V-shaped, of another curved cut wherein a portion of the material is not cut (wherein a bend is provided). As also shown in  FIG. 11 , a possibly most preferred roller wheel platform  80 - 1  of the invention may employ an elliptical foot contacting member  90 - 2  having two spaced, opposingly oriented, and curved cuts, enabling a downward bending of the two portions of plate material within the cuts, thereby forming the two opposing downwardly angled portions  22   a —one for each includable roller wheel assembly of the roller wheel platform  80 - 1 . 
     Returning briefly to  FIGS. 6B and 7B , it must be understood that the bearing-based rotatable coupling  40  of the present roller wheel assemblies and roller wheel platforms of the invention enable an individual to fully tilt a center coupling  70  and or a top member fixed thereto to cause a very sharp turning (say with a minimal turning radius of 1 to 2 feet), while maintaining each roller wheel fully and substantially in contact with the ground surface. Accordingly, even when a user is fully tilting (e.g., firmly contacting included stop posts  28 ) an upper foot contacting member, causing a maximum amount of steering and turning supported by the roller wheel assembly, all roller wheels will substantially remain in contact with the ground surface  100  upon which the roller wheel platform is rolling. This greatly reduces lateral slipping and ‘sliding out’ of one of the front end or rear end of the roller wheel platform. 
     While there have been described herein a plurality of the currently preferred embodiments of the means and methods of the present invention, those skilled in the art will recognize that other and further modifications may be made without departing from the invention. For example, available foot contacting means, instead of the simple flattened structures of  FIGS. 7A ,  7 B,  8 , and  11 , other foot engaging structures may be employed. For example, considering the boot embodiment  90 - 1  of  FIGS. 9A and 9B , a version of the roller wheel platform of  FIG. 4 , may be employed with a shorter wheelbase provided by a shorter center coupling  70 . In addition, the wheel track (width) of the embodiment of the roller wheel assembly  90 - 1  may be desirable. 
     Further, the roller wheels  30  of the presently described embodiments of the invention may be replaced by studded wheels or alternately ‘ice blades’ (neither illustrated herein), or other ground contacting members. In addition, other possible accessory structures may be included with the present invention. For example, as shown in the  FIG. 10  depiction of the boot embodiment  90 - 1 , a friction brake  60  may be included. As depicted, a brake mounting bracket  66  may be included having a first portion  66   a  and an second bracket portion  66   b . As illustrated, the first portion  66   a  may be fixed to the downwardly angled portion  22   b , while the ground contacting braking portion  62  may be best fixed to the second bracket portion  66   b . Yet other accessory portions may be provided, including reflectors, training and or safely wheels, etc. 
     As such, the foregoing descriptions of the specific embodiments of the present invention have been provided for the purposes of illustration, description, and enablement. They are not intended to be exhaustive or to limit the invention to the specific forms disclosed and or illustrated. Obviously numerous modifications and alterations are possible in light of the above teachings, and it is fully intended to claim all modifications and variations that fall within the scope of the appended claims provided hereinafter.