Fluid resistivity reducing structure of cylindrial body

Abstract

An object of the invention is to reduce a fluid resistance generated on a cylindrical body. A fluid resistivity reducing structure for reducing the fluid resistance generated on the cylindrical body B which relatively moves in a fluid comprises: a groove M provided on a surface S of the cylindrical body B, wherein: the groove M is constituted so as to extend roughly in a longitudinal direction of the cylindrical body; and so as to introduce the fluid moving along the surface of the body into the groove.

What is claimed is:  
     
         1 . A fluid resistivity reducing structure for reducing a resistive force generated on a substantially cylindrical body which relatively moves in a fluid, comprising: 
 at least a groove which is provided on a surface of said cylindrical body, wherein:    said groove is constituted so as to extend roughly in a longitudinal direction and so as to introduce said fluid which moves along said surface of said body into said groove.    
     
     
         2 . The structure according to    claim 1   , wherein: 
 said groove is approximately straight.    
     
     
         3 . The structure according to    claim 1   , wherein: 
 said groove extends in said longitudinal direction of said cylindrical body exhibiting roughly a snaky motion.    
     
     
         4 . The structure according to    claim 1   , wherein: 
 said groove extends in said longitudinal direction of said cylindrical body exhibiting roughly a spiral motion around said body.    
     
     
         5 . The structure according to claims  1 - 4 , wherein: 
 said groove is provided at least on a partial surface of said body.    
     
     
         6 . The structure according to claims  1 - 5 , wherein: 
 said cylindrical body is a golf club shaft.