Golf club

Abstract

A golf club comprises a shaft and a head, wherein a moment Ix of inertia of the golf club head around a vertical axis passing through the center of gravity of the club head is not less than 3800 (g·sq.cm), and a shaft-torque T (degrees) of the golf club shaft and the moment Ix of inertia satisfy the following condition (1): T=<0.0025×Ix−6.0.

1 . A golf club comprising 
 a golf club shaft and    a golf club head attached to a tip end of the golf club shaft, wherein    a moment Ix of inertia of the golf club head around a vertical axis passing through the center of gravity of the club head is not less than 3800 g·sq.cm, and    a shaft-torque T degrees of the golf club shaft and the moment Ix of inertia satisfy the following condition (1): T=<0.0025×Ix−6.0.    
     
     
         2 . The golf club according to  claim 1 , wherein 
 the shaft-torque T is in a range of from 1.5 to 6.0 degrees.    
     
     
         3 . The golf club according to  claim 1  or  2 , wherein 
 the shaft-torque and the moment Ix of inertia satisfy the following condition (2): T=<0.0025×Ix−6.3.    
     
     
         4 . The golf club according to  claim 1  or  2 , wherein 
 the shaft-torque and the moment Ix of inertia satisfy the following condition (3): T=>0.0025×Ix−8.5.    
     
     
         5 . The golf club according to  claim 1  or  2 , wherein the moment Ix of inertia is in a range of from 4100 to 5500 g·sq.cm.  
     
     
         6 . A method of designing a golf club composed of a club shaft and a club head, comprising 
 providing a moment Ix of inertia of not less than 3800 g·sq.cm for the club head, and determining a shaft-torque T degrees of the club shaft so as to satisfy the following condition (1): T=<0.0025×Ix−6.0.    
     
     
         7 . The method according to  claim 6 , which further comprises 
 determining the shaft-torque T degrees so as to satisfy the following condition (3): T>=0.0025×Ix−8.5 in addition to said condition (1): T=<0.0025×Ix−6.0.    
     
     
         8 . The method according to  claim 6  or  7 , which further comprises 
 providing a head volume of not less than 300 cc for the club head.    
     
     
         9 . The method according to  claim 6  or  7 , which further comprises 
 providing a weight of not less than 170 g for the club head.    
     
     
         10 . The method according to  claim 6  or  7 , which further comprises 
 providing an overall length L of not less than 43 inches for the club.