Strengthened and vibration-damping shaft for sports equipment

Abstract

A strengthening and vibration-damping shaft for sports equipment has a tube, a central body accommodated inside the tube, and multiple damping holes defined in the central body partly or completely along the length of of the central body. The central body provides a supporting efficiency to the shaft to prevent the shaft curving or deforming when the shaft is being swung. The damping holes mitigate and decrease vibration transmission to eliminate most vibrating energy. Therefore, the shaft has less vibration to keep the shaft steady for accurate hitting without deformation.

1 . A strengthening and vibration-damping shaft for sports equipment comprising: 
 a tube having an inner channel with an inner periphery;    a central body longitudinally accommodated inside the inner channel and having at least two sides respectively abutting to the inner periphery of the tube; and    multiple damping holes longitudinally defined in the central body at intervals.    
   
   
       2 . The strengthening and vibration-damping shaft as claimed in  claim 1 , wherein the multiple damping holes are respectively defined at sides of the central body.  
   
   
       3 . The strengthening and vibration-damping shaft as claimed in  claim 2 , wherein each of the multiple damping holes is a segment with an arcuate edge and a flat edge; and 
 the flat edge of the damping hole is adjacent to the inner periphery of the tube.    
   
   
       4 . The strengthening and vibration-damping shaft as claimed in  claim 3 , wherein the multiple damping holes are defined along an entire length of the central body.  
   
   
       5 . The strengthening and vibration-damping shaft as claimed in  claim 3 , wherein the multiple damping holes are defined along part of a length of the central body.  
   
   
       6 . The strengthening and vibration-damping shaft as claimed in  claim 1 , wherein the central body is cruciform in cross-section.  
   
   
       7 . The strengthening and vibration-damping shaft as claimed in  claim 1 , wherein the central body is straight in cross-section.  
   
   
       8 . The strengthening and vibration-damping shaft as claimed in  claim 1 , wherein the tube is round in cross-section.  
   
   
       9 . The strengthening and vibration-damping shaft as claimed in  claim 1 , wherein the tube is oval in cross-section.