Swingweight adjusted golf club shaft

Abstract

An improved golf club shaft and corresponding golf club is disclosed. More specifically, a golf club shaft that is capable of minimizing or eliminating swingweight variations within a golf club despite being cut down to various different lengths to accommodate the length and heads of a set of irons is disclosed. The shaft may have an internal wall profile of variable thickness to adjust for various weight and center of gravity variations of a golf club shaft as it is being cut down in length.

1 . A plurality of golf clubs comprising:
 a first golf club containing a first shaft having a first fulcrum utilizing a blank shaft;   a second golf club containing a second shaft having a second fulcrum also utilizing said blank shaft;
 wherein said second shaft is foamed by cutting down the length of said blank shaft; and 
   wherein an internal wall profile within said blank shaft allows a total moment of said second golf to be similar to a total moment of said first golf club.   
     
     
         2 . The plurality of golf clubs in  claim 1 , wherein said internal wall profile causes a shaft moment about said second fulcrum to change 10 gram·inchs to 50 gram·inchs for each half inch reduction in length from said first shaft. 
     
     
         3 . The plurality of golf clubs in  claim 2 , wherein said half inch reduction in length is achieved by cutting said blank shaft at said tip end of said blank shaft. 
     
     
         4 . The plurality of golf clubs in  claim 3 , wherein said blank shaft has a constant outer diameter at a tip end of said blank shaft for a distance of from 2.5 inches to 12 inches. 
     
     
         5 . The plurality of golf clubs in  claim 3 , wherein said blank shaft may have a tapered outer diameter at a tip end of said blank shaft for a distance of from 0.75 inches to 6 inches. 
     
     
         6 . The plurality of golf clubs in  claim 3 , wherein said internal wall profile causes said moment about said second fulcrum to change 15 gram·inchs to 50 gram·inchs for each half inch reduction in length from said blank shaft. 
     
     
         7 . The plurality of golf clubs in  claim 6 , wherein said internal wall profile is sinusoidal in shape. 
     
     
         8 . The plurality of golf clubs in  claim 6 , wherein said internal wall profile has a wall thickness that increases linearly from said first end of said first golf club towards said first end of said second golf club for a distance of 2.5 inches to 12 inches. 
     
     
         9 . The plurality of golf clubs in  claim 6 , wherein said internal wall profile is stair-stepped in shape.