Abstract:
There is disclosed herein an improved and simplified wheel and bearing assembly, such as for skates and the like comprising a bearing inner race preferably formed of a plastic material such as polysulfone. A pair of bearing outer races, preferably of a relatively strong material such as titanium or polysulfone, are coupled with outer surfaces of the bearing inner race. Mating surfaces of the bearing inner race and the bearing outer races are configured and are coated with a lubricant to provide bearing surfaces for the wheel. The wheel includes a tire with a glow-in-the-dark material or a reflective material.

Description:
[0001]     The present invention relates to wheels, and more particularly to a relatively simple wheel and bearing assembly useful for skates, skateboards, scooters, luggage, shopping carts, toys and the like.  
       BACKGROUND OF THE INVENTION  
       [0002]     Various forms of wheels, including skate wheels, have been developed over the years. A typical skate wheel, for example, comprises a rigid annular hub onto which an outer tire is mounted or directly molded thereon. The hub usually is supported by one or a pair of radial bearings which are attached by a shaft to the skate. Wheels for other sports and like items usually have a similar construction. The bearing typically is a ball bearing.  
       SUMMARY OF THE INVENTION  
       [0003]     In accordance with a preferred embodiment of the present invention, a new form of wheel and bearing assembly particularly useful for skates, skateboards, and other wheeled devices, as well as toy products, does not incorporate the usual ball bearing assembly but rather comprises a hub in the form of a bearing inner race which supports a tire, and a pair of bearing outer races coupled with the inner race. Certain outer surfaces of the bearing inner race and certain inner surfaces of the bearing outer races are configured in a manner to form a mating bearing having a dry film lubricant on the mating surfaces. The tire is molded or otherwise disposed on the inner race and which preferably is formed of polyurethane. The bearing outer races preferably are machined from titanium, aluminum, or a suitable polyurethane, but preferably from polysulfone. The outer races also preferably are formed of polysulfone and mate and snap together. The mating surfaces of the inner race and outer races are provided with a suitable solid film lubricant.  
         [0004]     Accordingly, it is a principal object of the present invention to provide a new form of wheel and bearing assembly.  
         [0005]     Another object of the present invention is to provide a simple form of wheel suitable for use for skates, skateboards, toys, and other wheeled uses. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]      FIG. 1   a  illustrates a completed wheel and bearing assembly and  FIG. 1   b  and  FIG. 1   c  illustrate, respectively, a “glow-in-the-dark” version and a reflective version according to the present invention;  
         [0007]      FIG. 2  is an exploded view showing the components of a wheel and bearing assembly of the present invention;  
         [0008]      FIGS. 3   a  and  3   b  are side elevational views of two embodiments thereof,  
         [0009]      FIGS. 4   a  and  4   b  are detailed cross-sectional views of the assembly, further showing an axle on which it can be mounted, wherein  FIG. 4   a  illustrates outer races of metal and  FIG. 4   b  illustrates outer races of plastic;  
         [0010]      FIGS. 5   a  and  5   b  are enlarged detailed cross-sectional views of a portion of an inner race and an outer race further illustrating the mating surfaces thereof, wherein  FIG. 5   a  illustrates an outer race of metal and  FIG. 5   b  illustrates an outer race of plastic.  
         [0011]      FIGS. 6   a  and  6   b  are perspective views of the wheel assembly with a snap lock for metal and plastic versions;  
         [0012]      FIGS. 7   a  and  7   b  are enlarged views of the bearing outer races illustrating extended portions coupling together the metal races ( 7   a ) allowing the plastic races to be snapped together ( 7   b ). 
     
    
     DETAILED DESCRIPTION  
       [0013]     Turning now to the drawings,  FIG. 1   a  illustrates a wheel  10  having an outer tire  12 , bearing inner race  14  forming a hub onto which the tire  12  is mounted or molded, and one bearing outer race  16   a  of a pair of bearing outer races  16   a ,  16   b .  FIG. 1   b  shows a version with a glow-in-the-dark material  11 , and  FIG. 1   c  shows a version with reflective material  13 .  
         [0014]      FIG. 2  is an exploded view of the wheel  10  better illustrating in particular the bearing inner race  14  and the bearing outer race  16   a  and bearing outer race  16   b  which mate with the inner race  14  on both sides thereof as will be apparent from a review of  FIG. 2  and  FIGS. 4   a  and  4   b .  FIG. 2  also illustrates cavities or pockets  30   c  and  32   c  which will be explained later.  
         [0015]      FIGS. 3   a  and  3   b  are elevational views further showing the wheel  10  and its components, and particularly the glow-in-the-dark material  11  and reflective material  13 .  
         [0016]     Turning now to  FIGS. 4 and 5 ,  FIG. 4  is a detailed cross-sectional view of the entire wheel  10  further illustrating the tire  12 , bearing inner race  14  onto which the tire is disposed, and the pair of bearing outer races  16   a  and  16   b .  FIG. 4  further illustrates an axle  20 , and nut  22  or other fastener, which extends through the outer races  16   a ,  16   b  and secures them to the item to which the wheel  10  is attached, such as an inline skate, a skateboard, or other wheeled device (not shown).  FIGS. 4   a  and  5   a  illustrate the outer race  16  formed of metal, and  FIGS. 4   b  and  5   b  illustrate the outer race  16  formed of plastic. Both of the glow in the dark material  11  and the reflective material  13  are shown in  FIGS. 4 and 6  for illustration, it being understood that one or the other would be present, usually not both.  
         [0017]     Exemplary materials comprise a suitable plastic for the tire  12 , such as polyurethane. The bearing inner race  14  preferably is formed of polysulfone and can include holes into which the tire material can flow during molding. The bearing outer races  16   a ,  16   b  can be formed of various materials depending on the uses to which the wheel  10  will be placed. For example, for high impact uses, preferably the bearing outer races  16   a ,  16   b  are metal, such as machined of titanium. For medium duty, 7075 aluminum is suitable, and for light duty, polyurethane 80D Shore hardness is suitable. Polysulfone is particularly good for the races  16 .  
         [0018]     Still referring to  FIG. 4 , and particularly to the detail in  FIG. 5 , an important aspect of the present invention is the generally “V” configuration of surfaces  30   a ,  30   b , and  32   a ,  32   b . Surfaces  30   a ,  30   b  in an exemplary embodiment can be 30 degrees with respect to the axis of the wheel, and surfaces  32   a ,  32   b  can be 29 degrees with respect to the axis of the wheel. Importantly, each of these surfaces  30   a ,  30   b ,  32   a  and  32   b  is coated with a solid film lubricant such as Everlube 620C sold by Everlube Products. The surfaces  30   a ,  30   b ,  32   a  and  32   b  are shown in heavy lines in  FIGS. 5   a  and  5   b  to represent this coating. The surfaces  30   a ,  32   a , of the race  14  are impregnated with lubricant during molding of the race  14 . The lubricant is baked on the surfaces  30   b  and  32   b  of the races  16   a  and  16   b.    
         [0019]     Importantly, the races  16   a  and  16   b  further include pockets  30   c  and  32   c  as seen particularly in  FIG. 5  for containing respective lubricant  30   d  and  32   d . These pockets  30   c  and  32   c  not only reduce the surface area and contact between races  16  and  14 , but also provide improved lubrication. Thus, not only is there surface lubrication as indicated by the heavy lines  30   a ,  30   b ,  32   a  and  32   b , but also lubricant  30   d  and  32   d  is provided in the respective pockets  30   c  and  32   c.  The total surface removal for forming the pockets  30   d  and  32   d  is approximately 25-30 percent, and preferably 27 percent. The pockets  30   d  and  32   d  are too small in  FIGS. 4   a  and  4   b  to label.  
         [0020]     The inner race  14  can be molded, and the tire  12  can be molded onto the outer circumference of the inner race  14 , or mounted thereon in any other suitable manner. When the tire  12  is worn, the tire  12  and race  14  (which acts as a hub) assembly is discarded.  
         [0021]     Other important aspects of the present invention are the manner in which either the metal or the plastic bearing outer races  16   a  and  16   b  are configured so that their inner ends  16   c - 16   f  fit together. In the case of the metal races in FIG.  4   a  the outer race  16   a  has an annular skirt  16   c  which fits within an annular opening in race  16   b  defined by an annular skirt  16   d.  Of particular significance is the manner in which annular segments  16   e  of race  16   a  fit with annular segments  16   f  of race  16   b  so that the plastic races  16   a  and  16   b  can be snapped together. The structure of the annular segments is better seen in  FIGS. 7   a  and  7   b . The skirts or segments  16   c  and  16   d  in each of outer races  16   a  and  16   b  are alike and in the assembly of the races  16   a  and  16   b  together, race  16   c  mates with  16   d , and this keeps race  16   a  from rotating with respect to race  16   b . In a similar manner, the annular skirts or segments  16   e  and  16   f  not only mate together but they do so in a snapping fashion because of a raised area  34   a  and a groove  34   b.    
         [0022]     Turning again to  FIG. 4 , it is preferable that the tire  12  be formed of a transparent or translucent material, clear or coated, and further include either a glow-in-the-dark material  11  or a reflector  13 . Both could be used, but this would present a difficult construction or molding problem and, thus, the preference is that if glow-in-the-dark material is used, it be in the form of an annular ring  11  (or reflector  13  not be present) within the tire  12 , or alternatively only the reflector  13  is provided as an annular ring within the tire  12 .  
         [0023]     As noted earlier, wheels according to the present invention are particularly useful for skate devices, such as inline skates, skateboards, as well as toys. Furthermore, wheels according to the present invention can be used in other applications, such as scooters, luggage, shopping carts, even including items such as bicycles and the like, and industrial equipment.  
         [0024]     While embodiments of the present invention have been shown and described, various modifications may be made without departing from the scope of the present invention, and all such modifications and equivalents are intended to be covered.