Abstract:
A skateboard having a board on which a skateboarder stands or sits and a pair of truck assemblies, each truck assembly including a base member for attachment to one side of the board, a roller bracket for supporting a roller on the base member, and apparatus for pivotably coupling the roller bracket to the base member, including apparatus for normally urging the bracket to a centered position relative to the coupling apparatus. The base member further includes a pair of projections arranged parallel to one another and spaced apart a distance which is sufficient to accept the thickness of the roller bracket. The roller bracket includes opposing arm portions and a connecting bight portion. The projections include apertures which are aligned with one another and with an aperture in the bight portion of the roller bracket, and fasteners are provided for securing together the roller bracket bight portion and the projections such that the bight portion is pivotally supported between the projections for pivoting motion about the fasteners.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to skateboards, and more particularly to a skateboard having a single pair of rollers attached to the underside of a support platform for supporting a human user standing on the platform, and a truck assembly having a novel roller and roller support structure. 
     2. Description of the Related Art 
     Wheeled personal recreational apparatus of the type used for exercise or pleasure have been known for years. Some of the more common contemporary devices are roller skates and roller skis, and skate boards. These devices typically consist of a support platform for supporting the user who stands or sits on the platform and a plurality of wheels or rollers, typically at least four, supported by the underside of the platform. 
     In recent years, improvements in such devices have been directed to a variety of aspects of construction as well as function. Some improvements relate to the boards themselves, as illustrated by U.S. Pat. No. 4,061,350 to Schmidt, Jr. et al which provides a modular wheel assembly construction that is designed for easier attachment to the underside of the skate board. Other improvements relate to the manner in which the wheels or rollers are supported to the board, as evidenced by U.S. Pat. No. 4,138,127 to Kimmell et al. which discloses a two wheel roller skate in which the two wheels rotate about parallel axes and are each supported in a cradle for rotation about an axis normal to the parallel axes. Other teachings relate to suspension arrangements associated with wheels or rollers for the skating devices, as for example the structure shown in U.S. Pat. No. 4,202,558 to Olschewski et al in which there is shown an elastic support member for rollers of skating devices wherein each support member includes a pin element extending at an acute angle downwardly from the mounting plate in a bore in the support member in such a manner that one end of the pin engages against the shaft of the roller and retains it in the bore. U.S. Pat. No. 4,168,842 to Kimmell et al. discloses a truck configuration for skate boards. Still other improvements relate to the wheel structure, as evidenced by U.S. Pat. No. 4,034,995 to Forward et al. which shows a skate including a boot having forward and rearward hollow spheroidal rollers in lieu of wheels. 
     One of the more significant problem areas encountered in the design of skate boards and the like relates to steering, while maintaining stability of the board. Typically, a truck is used to support a wheel and axle assembly to enable such steering, with the steering being accomplished by the shifting of the weight of the rider to one side of the of the board or the other side . Each of the front and rear roller assemblies in conventional skate boards are mounted in mirror image relation to one another to permit the two pairs of wheels to turn simultaneously in opposite directions resulting in both pairs of wheels defining an arc of a curve. 
     Typically, trucks for wheels used with skates and skate boards comprise a solid central member having spindles on opposite sides of the solid member for support of the wheels. Some truck designs also have cushion members to absorb jolts or biasing members to urge the wheel supporting trucks back to a centered position relative to the support board. 
     U.S. Pat. No. 3,995,873 to Pantzer discloses a two roller skateboard having a flat board with a pair of steerable rollers disposed about an underside thereof. Each of the two rollers are of substantial width, on the order of about one half of the overall width of the skateboard. Each roller is rotatably supported to the underside of the board in a manner to permit swivelling about a journal axis. A cantilevered leaf spring cooperates with a pinion in the journal for the swivel axis to return to a neutral position. The wider pair of roller offers stability to the rider at slower speeds and when the board is at rest; however, the Pantzer skateboard is still unstable and susceptible to tilting over during use because, although being wider than most wheels found in conventional skate boards, the limited width of the rollers contributes to board imbalance. 
     U.S. Pat. No. 5,160,155 to Barachet discloses a skateboard having two wheels mounted to an underside thereof, in which the rear wheel is fixed relative to the support board. The skateboard of Barachet has the disadvantage that the rear wheel protrudes through the surface of the board thereby making foot placement of the user on the board quite difficult. 
     Against this background of known technology, the applicant has developed a novel wheel structure which can be used for skates, a skateboard, skis for use on a hard surface, a scooter, or any other related vehicular device. A preferred embodiment includes a board on which a user stands, and a pair of wheel members arranged parallel to one another and attached to the underside of the board. Preferably, the wheel members comprise a roller, each of which is mounted on a bracket pivotally secured to a clevis attached to the underside of the board. The roller bracket includes resilient means for absorbing shocks during use and for biasing the roller bracket into a centered position on the clevis. Preferably, the rollers are elongated along the axis of rotation of the rollers, and the exterior surface of the rollers is tapered at each end of the roller to enhance steering and control of the board. 
     OBJECTS AND SUMMARY OF THE INVENTION 
     It is therefore an object of the present invention to provide a novel construction for a personal recreational device of the type on which a user stands and which is outfitted with rollers pivotably supported relative to the device that permit rolling motion of the device which is controlled by the user, and which will overcome many of the disadvantages and drawbacks of similar devices known in the art. 
     Another object of the present invention is to provide a novel skate board design which includes forward and rearward rollers attached to the underside of a board, where the rollers have an elongated barrel shape with tapered ends which facilitate steering and control of motion of the board. 
     Still another object of the invention is to provide a set of rollers, each of which includes a roller element having a central portion and end portions, the roller being of elongated configuration along the axis of rotation. 
     Still another object of the invention is to provide a skateboard which uses a compressive pad of resilient, rubber-like material which can be subjected to compressive stresses by a roller-carrying bracket during turning such that the compressive pad will restore the bracket to its normally-centered position after completion of the turn, thereby assuring optimum simplicity in the turning or steering of the skateboard. 
     Still another object of the invention is to provide a kit for converting a conventional skate board to the board of the present invention, the kit including a set of trucks each having a base portion, elastic cushion means on the base portion, a bracket, and a roller mounted by the bracket to the truck. 
     Other objects, advantages and features of the invention will become more apparent, as will equivalent structures which are intended to be covered herein, with the teaching of the principles of the invention in connection with the disclosure of the preferred embodiments thereof in the specification, claims and drawings in which: 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a side view of the skate board  10  according to the present invention; 
     FIG. 2 is a perspective view of a truck assembly  20  according to the present invention, 
     FIG. 3 is a side view of the truck assembly  20  shown in FIG. 2; 
     FIG. 4 is a plan view of the roller bracket  24  shown in FIG. 3; and 
     FIG. 5 is a sectional view of the roller  60  shown in FIG.  2 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The following description is provided to enable any person skilled in the art to make and use the invention and sets forth the best modes contemplated by the inventor of carrying out his invention. Various modifications, however, will remain readily apparent to those skilled in the art, since the generic principles of the present invention have been defined herein specifically to provide a novel personal recreational device, such as a skate or skateboard, that encompasses many long sought after features not found in relevant prior devices. 
     Referring now to FIG. 1, there is shown a skateboard  10  which comprises a board or platform  12  and a pair of truck assemblies  20  supported and secured to the underside of the board  12 . It is contemplated that the board  12  as used in accordance with the teachings of the present invention is a conventional board found in a variety of sports shops. 
     The truck assemblies are designed to be secured to the underside of the board via screws or bolts (see  52  in FIG. 2) that are provided with such conventional boards. 
     Referring now specifically to FIGS. 2 and 3, each truck assembly is seen to include a base member  30  having through holes (not shown) for receipt of threaded fasteners  52 , as for example bolts or screws, in order to secure the base portion of the truck assembly to the underside of the skateboard. Generally, a conventional skateboard  12  is provided with pre-drilled openings (most often on the underside thereof) which are typically threaded. These openings receive the threaded fasteners  52  for enabling secure attachment of the truck assembly to the platform of the skateboard. 
     The base member  30  of the truck assembly comprises a substantially planar plate portion  32  and includes a pair of ears  34   a ,  34   b  which are disposed parallel to one another and spaced apart by an amount sufficient to receive therebetween the thickness of the bight portion  24  of the roller bracket  22  and a resilient biasing member or cushion  42 . The resilient member or cushion  42  is preferably made of a compressible material such as rubber, neoprene, a soft plastic or similar material, and is arranged between the ears  34   a ,  34   b  as well as between the roller bracket bight portion  24  and the surface of the base member adjacent to the bight portion of the roller bracket  22 . A bolt  50  having a threaded shank defining a longitudinal axis is provided for passage through aligned openings  36  (only one opening is shown in ear  34   a , but it is to be understood that an opening of similar size is also provided in ear  34   b ) and an opening in the bight portion  24  of the roller bracket  22  to pivotably secure the roller bracket  24  to the ears  34   a ,  34   b . The externally threaded bolt  50  is secured in place by an internally threaded nut  52  positioned adjacent to the ear  34   b . The nut, when tightened, presses against the outer surface of the ear  34   b , as shown in FIG. 3, thereby drawing the ears together and firmly holding the roller bracket therebetween. Although the bracket is secured to the ears  34   a ,  34   b , it is nevertheless free to pivot laterally from side to side about the longitudinal axis of the bolt  50 , the latter due to the fact that the diameter of the openings  36  in the ears is greater than the diameter of the threaded bolt  50 . The resilient biasing member or cushion  42  is disposed between the planar plate portion  32  of the truck assembly and the bight portion  24  of the bracket, and provides a biasing force on the bracket when the bracket is pivotally displaced about the bolt  50  from the substantially centered position depicted in FIG. 2 relative to the truck assembly base member (the reasons for which will become clearer when discussed below. 
     The roller bracket  22  (see FIG. 2,  3  and  4 ) comprises a U-shaped structure having two substantially parallel arms  26   a ,  26   b  extending in a first direction P from one side of the bight portion  24 . A throughhole  25  is formed in the bight portion  24  and is positioned to be in alignment with the openings  36  in the ears  34   a ,  34   b  when the roller bracket is mounted to ears  34   a ,  34   b  of the base member  30 . The terminal region  28  of each arm includes an opening  29 ,  29 ′. 
     The longitudinal axes of openings  29 ,  29 ′ are substantially coincident and arranged substantially normal to the first direction P as well as the longitudinal axis of bolt  50 . Preferably, the through hole  25 , and the through openings  29 ,  29 ′, are provided with bushings that line the interior surfaces thereof. The portion of the bight portion  24  opposite the arms includes a cutout region  38  for engagement with the resilient member  42 . As noted above, the bracket bight portion, while being able to rock about the “pivot” formed by the bolt  50 , is also biased into a centered position relative to the “pivot” such that the outer extents of the bight portion (i.e., the region where the arms  26   a ,  26   b  merge with the bight portion  24 ) are equally spaced from the base member. 
     The arms  26   a ,  26   b  of the roller bracket  22  support the roller  60  (see FIG.  2 ). The roller  60  is an elongated substantially cylindrical member having a longitudinal length L corresponding to the distance between the facing surfaces of the arms  26 , 26 ′ of the roller bracket  22 . The roller  60 , which has a central longitudinal bore  61  therein, is preferably made of a material which is durable and exhibits low frictional characteristics, as for example, teflon, nylon, Delrin or urethane. As seen in FIGS. 2 and 5, the roller has a substantially cylindrical central portion  62  having an outer surface of a first diameter, and end portions  64  which are tapered so that the diameter of the outer surface of the roller  60  at the tapered end portions  64  is smaller than at the diameter of the outer surface of the central portion  62 . The tapered outer portions of the roller  60  facilitate steering and control of the skateboard during its use. 
     Bearing assemblies  66   a ,  66   b  are mounted at respective ends of the roller bore  67 . A hollow metal bushing  63  is mounted in the axial bore  61  of the roller  60 . Preferably, the bushing is made of a tough material, such as plastic or metal. The longitudinally inner ends of the bearing assemblies are seated against the longitudinally outer ends of the bushing. The diameter of the bushing bore is approximately the same as the diameter of the bores of the bearing assemblies. A rod  70  is axially disposed within the roller  60  and extends within the bores of the bearing assemblies and the bushing. Ends  72 , 72 ′ of the rod are externally threaded and protrude axially away from opposite ends of the roller. In assembling the roller  60  to the roller bracket  22 , the roller is first positioned between the roller bracket arms  26   a ,  26   b  and then the rod  70  is inserted through one of the openings in a first of the bracket arms and pushed through the roller inside the bushing until it extends from the opposite side of the roller and through the other of the openings in the second of the bracket arms. Nuts  75  are secured to the threaded ends of the rod on the outside of the bracket arms. Tightening the nuts on the threaded ends of the rod  70  squeezes the arms together and into compressive engagement with the bearing assemblies  66   a ,  66   b , which in turn press the bearing assemblies longitudinally inward and into compressive engagement with the bushing. In this way, the inner races of the bearing assemblies are locked together with the bushing  63  and the bracket arms  26   a ,  26   b  and prevented from rotating relative to the roller, while the outer races of the bearing assemblies, on which the roller body is mounted, are free to rotate about the longitudinal axis. 
     The purpose of the pivoted connection between the bracket  22  and the base member  30  as well as the compressible cushion  42  and the novel roller  60  is to facilitate steering and/or control of the skateboard when in motion. 
     As was briefly mentioned above in connection with the discussion of relevant known devices, steering of skateboards in general, and of the skateboard of the present invention requires, as known from the prior developed skateboards, a shift of the weight of the user to the side of the board to which the user wishes to steer. 
     The skateboard of the present invention provides superior stability, control and steering capabilities due to the novel configuration of roller  60  and the connection between the bracket for the roller and the compressible cushion  42 . When a user desires to effect a turning maneuver, he or she typically shifts his feet from a position which is more or less centered relative to the upper surface of the support board to a position where his or her feet are closer to that side of the support board to which a turn is to be made. Steering is accomplished by the user&#39;s shifting his or her weight relative to the center of gravity of the skateboard, or by moving his or her feet from a central region of the skateboard to a lateral region of the board. Such shifting or moving of the feet on the board causes the bracket  22  to pivot about the bolt  50 , and the weight of the user and the board to shift from the central region  62  of the roller toward one of the end portions  64  of the roller  60 . The roller bracket  22  pivots relative to the truck base member  30  about the bolt  50 , and after the turn has been made, when the user shifts his or her weight toward the central portion of the support board, the resilient biasing member  42  urges the roller bracket  22  back toward the centered position seen in FIG.  2 . 
     That this action takes place without severe tipping or overturning of the board of the present invention is a testament to the novel configuration of the roller  60 . In similar prior devices, as exemplified by U.S. Pat. No. 3,995,875 to Pantzar (discussed above), the width of the roller is approximately no more than one half of the width of the skateboard. The flat uniform surface of the Pantzar roller coupled with the limited length reduces the turning capability and stability of the board insofar as when the user shifts his/her weight to one side of the board to effect a turning/steering action, one side of the roller is caused to lift off the ground followed by a tipping action of the board to such an extent that the edge of the board opposite the side of the roller that has been raised off the ground moves toward or into contact with the ground, thereby placing the user of the board in jeopardy of serious injury. Instability of the Pantzar board is amplified when the user attempts to make a tight turn or when the user possesses great weight. 
     In contrast, the roller configuration of the present invention will easily accommodate overweight users while permitting, for any user, tilting of the board (and roller) in such a manner as to effect tight turns while maintaining substantial stability. Preferably, the width of the roller of the present invention is very nearly 75% of the width of the skateboard, if not wider. The added width, and the sloped shoulders, of the roller configuration disclosed herein permits tilting of the board while maintaining a substantial portion of the surface of the roller in contact with the ground during nearly all steering maneuvers. Moreover, the roller bracket  22  allows the board to rest on it when the board is tipped to its maximum angle of tipping. The design of the roller of the present invention, along with the roller supporting structure, provides optimum assurance that, when the user effects an extreme turning maneuver, no edge of the board will be able to make contact with the ground, and the board will not overturn and will remain stable. 
     The present invention also embraces providing, in appropriate packaging (not shown), a kit comprising one, or two, of the truck assemblies for the purpose of converting a conventional skateboard to a board of the type described herein in accordance with the teachings of this invention. It is also contemplated that a user could repair or replace one or both of the trucks attached to the skateboard of the present invention as described herein. 
     Those skilled in the art will appreciate that various adoptions and modifications of the invention as described above can be configured without departing from the scope and spirit of the invention. Therefore, it is to be understood that, within the scope of the appended claims, the invention may be practiced other than as specifically described herein.