Golf club head with adjustable center of gravity

Abstract

A golf club includes a golf club head with a loft at least 40 degrees and a weight member movably coupled to a rear surface. In a first configuration, the golf club head has a first center of gravity, CG1, and a first moment of inertia about a vertical axis therethrough, Izz1, and a first swingweight, SW1. In a second configuration, the golf club head has a second center of gravity, CG2, and a second moment of inertia about a vertical axis therethrough, Izz2, that is at least 500 g*cm2 greater than Izz1, and a second swingweight, SW2 that is within 1.75 inch-oz of SW1. In another aspect, when a weight member is in a second position at least 2 cm away from a first position, the golf club has a second swingweight SW2 that is within 1.75 inch-oz of a first swingweight SW1 for the first position.

We claim: 
     
         1 . A golf club that, when oriented in a reference position, comprises:
 a shaft having a butt end and a tip end;   a grip proximate the butt end of the shaft; and   a golf club head proximate the tip end of the shaft, the golf club head comprising:
 a loft greater than or equal to 40 degrees; 
 a main body including a heel, a toe opposite the heel, a striking face and a rear surface opposite the striking face; and 
 a weight member movably coupled to the rear surface such that:
 in a first configuration, the golf club head has a first center of gravity, CG 1 , and a first moment of inertia about a vertical axis therethrough, Izz 1 , and the golf club has a first swingweight, SW 1 ; and 
 in a second configuration, the golf club head has a second center of gravity, CG 2 , and a second moment of inertia about a vertical axis therethrough, Izz 2 , that is at least 500 g*cm2 greater than Izz 1 , and the golf club has a second swingweight, SW 2  that is within 1.75 inch-oz of SW 1 . 
 
   
     
     
         2 . The golf club of  claim 1 , wherein SW 2  is within 0.75 inch-oz of SW 1 . 
     
     
         3 . The golf club of  claim 1 , wherein the rear surface includes a track member and the weight member moves along the track member. 
     
     
         4 . The golf club of  claim 3 , wherein the track member extends substantially in a heel-toe direction. 
     
     
         5 . The golf club of  claim 1 , wherein Izz 2  is no more than 1,200 g*cm2 greater than Izz 1 . 
     
     
         6 . The golf club of  claim 1 , wherein the weight member is at least 5 g and no more than 50 g. 
     
     
         7 . The golf club of  claim 6 , wherein the weight member is at least 15 g and no more than 40 g. 
     
     
         8 . The golf club of  claim 1 , wherein the weight member has a density greater than that of the main body. 
     
     
         9 . The golf club of  claim 1 , wherein the weight member comprises a first material on one side and a second denser material on an opposite side. 
     
     
         10 . The golf club of  claim 9 , wherein the weight member is rotatable. 
     
     
         11 . A golf club that, when oriented in a reference position, comprises:
 a shaft having a butt end and a tip end;   a grip proximate the butt end of the shaft; and   a golf club head proximate the tip end of the shaft, the golf club head comprising:
 a main body including a heel, a toe, a striking face, a rear surface opposite the striking face, and a hosel defining a hosel axis; and 
 a weight member coupled to the rear surface and translatable along the rear surface in a direction substantially perpendicular to the hosel axis such that:
 when the weight member is in a first position, the golf club has a first swingweight SW 1 ; and 
 when the weight member is in a second position that is at least 2 cm away from the first position, the golf club has a second swingweight SW 2  that is within 1.75 inch-oz of SW 1 . 
 
   
     
     
         12 . The golf club of  claim 11 , wherein SW 2  is within 0.75 inch-oz of SW 1 . 
     
     
         13 . The golf club of  claim 11 , wherein the rear surface includes a track member and the weight member moves along the track member. 
     
     
         14 . The golf club of  claim 13 , wherein the track member extends substantially in a heel-toe direction. 
     
     
         15 . The golf club of  claim 11 , wherein the golf club head includes a loft no less than 40 degrees. 
     
     
         16 . The golf club of  claim 11 , wherein the weight member is at least 5 g and no more than 50 g. 
     
     
         17 . The golf club of  claim 16 , wherein the weight member is at least 15 g and no more than 40 g. 
     
     
         18 . The golf club of  claim 11 , wherein the weight member has a density greater than that of the main body. 
     
     
         19 . The golf club of  claim 11 , wherein the weight member comprises a first material on one side and a second denser material on an opposite side. 
     
     
         20 . The golf club of  claim 19 , wherein the weight member is rotatable.