Wheel frame for a skateboard

Abstract

An improved wheel frame for a skateboard, wherein slipping wheels connect with a skateboard body stably, comprises: a wheel frame main body having a screw hole on each side; two wheel axles for screwing in the screw hole of the wheel frame main body, wherein in each axle a through hole is set, the through hole has at least one longitudinal expansion joint in the thread for flexible expanding the diameter; and an expansion element for setting in the through hole of the both axles, wherein the diameter of the thread within the axle is forced to expand, so that the thread of the axles and the screw holes of the wheel frame main body are firmly held together.

1 . An improved wheel frame for a skateboard, wherein slipping wheels connect with said skateboard body stably, comprising:
 a wheel frame main body, which is set under said skateboard body, having a slipping wheel on each end;   characterized by:
 said wheel frame main body having a screw hole on each end and 
 two wheel axles, which are firmly screwed on both ends in said wheel frame main body for mounting said slipping wheel. 
   
     
     
         2 . The improved wheel frame for a skateboard of  claim 1 , wherein each wheel axle has a first end with a thread on an outer side for screwing in said screw hole on each end of said wheel frame main body. 
     
     
         3 . The improved wheel frame for a skateboard of  claim 2 , wherein each wheel axle has a through hole at said center for forming a hollow structure. 
     
     
         4 . The improved wheel frame for a skateboard of  claim 3 , wherein said wheel axle at said first end has at least one longitudinal expansion joint, and said through hole at said position of said first end has a stage part with a narrower diameter. 
     
     
         5 . The improved wheel frame for a skateboard of  claim 4 , wherein in said through hole of said wheel axle an expansion element having a larger diameter than that of said stage part is set; if said expansion element is pressed in said stage part, said external diameter of said first end is forced to expand and thereby said thread of first end and said screw hole of said wheel frame main body occlude firmly. 
     
     
         6 . The improved wheel frame for a skateboard of  claim 5 , wherein said expansion element is a cylinder with a cone on one end. 
     
     
         7 . The improved wheel frame for a skateboard of  claim 1 , wherein each wheel axle has a through hole at said center for family a hollow structure. 
     
     
         8 . The improved wheel frame for a skateboard of  claim 7 , wherein said wheel axle at said first end has at least one longitudinal expansion joint, and said through hole at said position of said first end has a stage part with a narrower diameter. 
     
     
         9 . The improved wheel frame for a skateboard of  claim 8 , wherein in said through hole of said wheel axle an expansion element having a larger diameter than that of said stage part is set; if said expansion element is pressed in said stage part, said external diameter of said first end is forced to expand and thereby said thread of first end and said screw hole of said wheel frame main body occlude firmly. 
     
     
         10 . The improved wheel frame for a skateboard of  claim 9 , wherein said expansion element is a cylinder with a cone on one end.