Abstract:
A novel skate platform wheel truck and wheel design is disclosed which permits reconfiguration of the wheels and truck to incorporate three wheels per truck, with a larger center wheel with a convex running surface, and smaller side wheels with a beveled edge. This configuration permits more fluid and responsive turning of the skateboard.

Description:
This application is a divisional application of application Ser. No. 08/600,309 filed Feb. 12, 1996, now U.S. Pat. No. 5,803,473 entitled CONFIGURABLE WHEEL TRUCK FOR SKATEBOARDS OR ROLLER SKATES INCORPORATING NOVEL WHEEL DESIGNS. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates primarily to skateboards and roller skates and more particularly, to an improved skate wheel truck and wheels incorporating novel wheel designs for use therewith. 
     2. Background Information 
     Skateboards are well known devices having numerous references in the art. It is also well known that they can be extremely dangerous to someone unskilled in their use. Early attempts to alleviate this problem resulted in such solutions are the eight-wheel skateboard having four wheels per truck as described in U.S. Pat. No. 4,062,557 and an improvement thereto found in U.S. Pat. No. 4,337,961 wherein an endless belt is positioned around paired wheels with each truck having two pair. An alternative, U.S. Pat. No. 4,515,379, addressed a similar but slightly different problem for unskilled skaters. When passing over uneven terrain or a curb, having an upward projection which may come in contact with the truck axle housing, causing an abrupt halt to the skateboards forward progress with potential danger to the use. The &#39;379 patent utilizes a small roller positioned axially between the wheel pairs and has a radius smaller than the truck wheels so that the roller would normally clear objects when a person is skating on a flat, level terrain, but the roller would engage an upward extending object and roll over rather than impacting upon the object. 
     However, as a skateboard rider becomes more skilled and begins to attempt acrobatic maneuvers and narrow radium turns as well as increasing travel speeds, the above-described devices tend to inhibit such use by increasing the turning radius when attempting acrobatics and turns and limiting the speed achievable by the rider. 
     For the more skilled rider, attention has been toward improving the design of the wheel, such as that found in U.S. Pat. No. 4,070,065 and U.S. Pat. No. 4,128,254 which are directed to increasing traction and resistance to sideways slip of the wheel during turn and to reduce loss of speed during sharp turns due to greatly increased rolling friction as a result of lip deformation of the wheel. 
     Thus, there is a need for skateboards having wheel truck configurations and wheel designs that provide a relatively stable and safe platform for the beginning use and, at the same time, can be reconfigured as the user gains experience with use of the board in order to perform acrobatics and turns such as can be found in exhibitions and contests of skateboarding. 
     Additional objects, advantages and novel features of the invention will be set forth in part in the description as follows, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims. 
     SUMMARY OF THE INVENTION 
     According to the present invention, there is provided a newly designed skateboard truck assembly configurable to incorporate three, four, five or more wheels per truck and arranged to provide the stability and control required by the skill of the use. Further, the wheels incorporate novel designs configurable toward enhancing the stability and smoothness of the ride whether in use by a beginner or by an expert. 
     Additionally, the truck is designed to be compatible with existing boards can be easily retrofit with the novel truck configuration of the present invention. 
     In one configuration, each truck assembly has three wheels placed in axial alignment. A large wide wheel is mounted in the center of the truck assembly with two smaller width wheels mounted axially on either side of the large center wheel. The center wheel has a convex shape. The center wheel has a small bevel at each edge and the small side wheels are beveled with the bevel forming the same angle as the center wheel edge bevels. 
     In another configuration, the center wheel is narrower than the previously described configuration and includes a pair of wheels mounted axially on either side of the center wheel for a total of five wheels per truck. The surface along the circumference of the wheel is flat, with the side wheel pairs having beveled surfaces. 
     It is envisioned the skateboard utilizes two of either of the above described truck assemblies and during use, while riding in a straight line, the two large center wheels ride on the convex surface of the wheels. As the rider shifts weight to begin a turn, the two center wheels roll off their center surface and onto the beveled edges of the side wheels and, during the turn, the harder the rider leans, the sharper the radius of the turn as the side wheels come into play, helping the user&#39;s control in keeping the board from tipping over. Further, the board is more stable at high speeds as two wheels run truer in form, enabling the user to exercise better control of the higher speed. 
     Accordingly, it is the object of the present invention to provide the skateboard having a ride with the more natural feeling of skimming across the surface of water or snow such as when using an actual surfboard or snowboard. A further object of the present invention is to provide a skateboard that is more stable at higher speeds and capable of greater range of motion including sharper radius turning than that of present skateboards. 
     It is a feature of the present invention to provide a skateboard or roller skate wheel truck configurable in either of two, three, four, five or more wheels per truck configurations, permitting the board to be readily adapted to the uses and skills of the rider. 
     Still other objects and advantages of the present invention will become readily apparent to those skilled in this art from the following detailed description wherein I have shown and described only the preferred embodiment of the invention, simply by way of illustration of the best mode contemplated by carrying out my invention. As will be realized, the invention is capable of modification in various obvious respects all without departing from the invention. Accordingly, the drawings and description are to be regarded as illustrative in nature, and not as restrictive. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other features, objects and advantages of the present invention will become better understood with reference to the following description, depending claims, and accompanying drawings where: 
     FIG. 1 is a perspective view of a skateboard incorporating the three-wheel configuration of the skateboard wheel truck and innovative wheel design of the present invention; 
     FIG. 2 is a cross-sectional view of the wheel truck in FIG. 1 showing an alternate embodiment of the innovative wheel design of the present invention; 
     FIG. 3 is a side view of the wheel truck. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to FIG. 1, an improved skateboard incorporating one embodiment of the present invention is generally illustrated at 10. Skateboard 10 includes a platform 12, a front carriage or wheel truck assembly 14, and a rear carriage or wheel truck assembly 16 in accordance with the present invention. Truck assemblies 14 and 16 are identical and are rotated 180° with each other and mounted on a mounting block 20 adjacent opposing ends of the platform 12. As each carriage or wheel truck assembly 14, 16 is identical, only truck assembly 14 of the various embodiments of the present invention will be described in detail. 
     Wheel truck assembly 14 comprises a mounting block 20 which is affixed to the lower surface 18 of platform 12 and a wheel mounting frame 22 including parallel arms or sidewalls 31 extending between a flange 34 and a rounded tip 32 and defining a rectangular opening 23 therebetween sufficient to receive a main or center wheel 24. Frame 22 includes openings 29 formed in the frame 22 sidewalls 31 for receiving in a relatively snug fit, wheel axle 28 for supporting wheels 24, 26 within frame 22 while permitting wheels 24, 26 to freely rotate on wheel bearings 30 formed within the wheels 24, 16. 
     It is to be understood that the wheels 24, 16, utilize wheel bearings 30 such as are now known in the art and which are formed in the interior of the wheels to rotate around axle 28. However, it is within the scope of this invention that as improvements are made in bearings and the like, they may be incorporated in the disclosed invention without departing from the spirit thereof. Further, frame 22 is connected, and referring now to FIG. 3, to mounting block 20 in a traditional manner shown in prior art methods of connecting wheel trucks to skateboards. However, it is within the scope of this invention that the angle, φ, will be varied, depending on the specific frame used for a specific configuration, and where the angle φ is defined as 0°≦φ°≦90°. 
     Wheel 24 has a diameter about its central axis typical of other skateboard wheels such as is known in the art with the pair of side wheels 26, having a slightly lesser diameter. The present invention, however, is directed to an innovative design of the wheels 24, 26, and their interrelation during operation, as will be discussed hereinafter. 
     In this embodiment, by way of example and not by way of limitation, wheel 24 has a width on the order of three inches. Wheel 24 includes a convex running surface 25 formed around the circumference of the wheel 24 and has a bevel 27 formed circumferentially on both edges around wheel 24. In the shown embodiment, and referring also to FIG. 2, each bevel is on the order of 3/4 inches wide as measured along a tangent axially along the surface 25 wheel 24 and forms and angle θ, on the order of 22°, with the aforementioned tangential line. 
     It will be understood by those skilled in the art that the above dimensions and angles are representative of this embodiment only and that combinations of other dimensions and angles where the surface 25 width is≧1/2&#34;, and where 2°≦angle θ≦45°, and where the surface 27/27&#39; width is ≧1/8&#34;, without departing from the scope or intent of the present invention. 
     Further, axle 28 extends beyond sidewalls 31 to permit auxiliary or secondary wheels 26 to be affixed in rotational alignment around axle 28. In the depicted embodiment, wheels 26 are narrower than wheel 24 and have a beveled circumferential surface 27&#39; with the bevel formed at, and as a continuation of the same angle θ as formed on wheel 24. 
     In the depicted embodiments, the wheels utilize bearings formed on the interior thereof, to permit the wheels to rotate around axle 28. Further, frame 22 is connected to mounting block 20 in a manner shown in prior art methods of connecting wheels to platform 12. 
     The running surface of the preferred embodiment can have a convex surface which is an elliptical circumferential surface 25. The bevel angle θ°, has the same range (2°-45°) as shown for bevel 27&#39; in FIG. 2. Further, the housing 22 of truck 14/16 is identical to that in FIG. 2, with the main or center wheel 24&#39; formed by having an elliptical curvature along the circumference thereof. 
     The present invention is directed to a novel skateboard/roller skate wheel design which, in use, provides for a smoother, more natural ride such as may be found when riding a snowboard or surfboard, is readily configurable to provide changes in various ride characteristics, such as stability, speed, turning radius, and providing for an even distribution of load on the wheels during turns and to innovative wheel truck frames which permit the characteristics inherent in the disclosed wheel design to be fully utilized. By way of example and not by way of limitation with respect to the configurability of the disclosed invention, another embodiment of the present invention, although not shown, envisions removing the secondary wheels of the embodiments depicted in FIGS. 2 and 4 to be removed and use would be on the center wheels of the 14/16 wheel truck. 
     And, although the innovative wheel truck is designed so as to provide a direct retrofit for existing wheel trucks, it is within the purview of the invention that the wheel truck herein described can be modified to fit new designs in skateboard/roller skate wheel truck mounting plates. 
     Whereas the present invention has been described in relation to the drawings attached hereto, it should be understood that other and further modifications, apart from those shown or suggested herein, may be made within the spirit and scope of this invention.