Counterbalanced wedges

Abstract

Described are embodiments of wedge-type golf clubs that include a counterbalance weight located at the butt end of the shaft. The shaft and/or grip of disclosed clubs can have reduced mass while the club head and the butt of the shaft can have increased mass compared to conventional clubs, which provides a similar overall total mass but with an increase in the moment of inertia (MOI). The increase in MOI compared to a conventional club of similar style and mass can provide increased swing stability during a stroke, decreasing unintentional waggling about the hand grip fulcrum. The added weight in the head and the added weight in the butt of the shaft can counterbalance each other so that the overall swingweight of the club can be about the same as for a conventional, non-counterbalanced club having the same total mass, thereby providing a familiar feel and easy playability.

1 . A wedge-type golf club comprising:
 a club head having a static loft angle greater than 45°;   a shaft having an upper end and a lower end that is coupled to the club head;   a hand grip coupled to the shaft between the upper end and the lower end; and   a counterbalance weight coupled to the upper end of the shaft, the counterbalance weight having a mass of at least 40 grams;   wherein the golf club has a total mass of at least 500 grams, a total length of from about 35 inches to about 38 inches, an MOI CG  of at least 600 kg*cm 2 , and an inertial efficiency of at least 13.5%, wherein inertial efficiency is a unitless ratio of the MOI CG  per unit length squared divided by the total club mass.   
     
     
         2 . The golf club of  claim 1 , wherein the golf club has an inertial efficiency of at least 14.8%. 
     
     
         3 - 5 . (canceled) 
     
     
         6 . The golf club of  claim 1 , wherein the counterbalance weight has a mass of at least 50 grams. 
     
     
         7 . The golf club of  claim 1 , wherein the golf club has a swingweight that is between 2.6 N*m and 2.8 N*m. 
     
     
         8 . The golf club of  claim 1 , wherein the counterbalance weight is removably coupled to the upper end of the shaft, or is positionally adjustable relative to the shaft. 
     
     
         9 . (canceled) 
     
     
         10 . The golf club of  claim 1 , wherein the hand grip has an outer gripping surface and the counterbalance weight has an outer surface, and the counterbalance weight is positioned above the hand grip such that the outer surface of the counterbalance weight is substantially contiguous with the outer gripping surface of the hand grip. 
     
     
         11 . The golf club of  claim 1 , wherein the shaft comprises a bi-matrix shaft that comprises graphite material in an upper portion of the shaft and steel in a lower portion or tip portion of the shaft. 
     
     
         12 . A wedge-type golf club comprising:
 a club head having a static loft angle greater than 45°;   a shaft having an upper end and a lower end that is coupled to the club head;   a hand grip coupled to the shaft between the upper end and the lower end; and   a counterbalance weight coupled to the upper end of the shaft separate from the grip;   wherein the counterbalance weight has a mass of at least 40 grams; and   wherein the golf club has a total mass of at least 500 grams, a total length of from about 35 inches to about 38 inches, an MOI CG  of at least 600 kg*cm 2 , and a swingweight that is in a range from about 2.5 N*m to about 3.0 N*m.   
     
     
         13 . The golf club of  claim 12 , wherein the couterbalanance weight has a mass of at least 50 grams. 
     
     
         14 . The golf club of  claim 12 , wherein the golf club has a swingweight that is in a range from about 2.6 N*m to about 2.8 N*m. 
     
     
         15 . (canceled) 
     
     
         16 . The golf club of  claim 12 , wherein the golf club's total mass is between 500 grams and 600 grams. 
     
     
         17 . The golf club of  claim 12 , wherein the counterbalance weight is removably coupled to the upper end of the shaft, or is positionally adjustable relative to the shaft. 
     
     
         18 . The golf club of  claim 12 , wherein the club head has a total mass of between 300 grams and 320 grams. 
     
     
         19 . The golf club of  claim 12 , wherein the hand grip has a radial outer gripping surface and the counterbalance weight has a radial outer surface, and the counterbalance weight is positioned above the hand grip such that the radial outer surface of the counterbalance weight is substantially contiguous with the radial outer gripping surface of the hand grip. 
     
     
         20 . The golf club of  claim 12 , wherein the shaft comprises a bi-matrix shaft that comprises graphite material in an upper portion of the shaft and steel in a lower portion or tip portion of the shaft. 
     
     
         21 . The golf club of  claim 1 , wherein the club head has a total mass of between 300 grams and 320 grams. 
     
     
         22 . The golf club of  claim 21 , wherein the hand grip and the shaft have a combined mass of 150 grams or less. 
     
     
         23 . The golf club of  claim 18 , wherein the hand grip and the shaft have a combined mass of 150 grams or less. 
     
     
         24 . A wedge-type golf club comprising:
 a wedge-type club head having a static loft angle greater than 45°;   a shaft having an upper end portion and having a lower end portion that is coupled to the club head;   a hand grip coupled to the upper end portion of the shaft, the hand grip having a lower hand grip portion positioned around the shaft and an upper hand grip portion that is positioned around the upper end portion of the shaft, wherein the upper hand grip portion has an outer diameter that is smaller than an outer diameter of the lower hand grip portion; and   a counterbalance weight positioned around the upper hand grip portion of the hand grip and positioned above the lower hand grip portion, the counterbalance weight having a greater density than the hand grip and the shaft;   wherein the lower hand grip portion has a radial outer gripping surface and the counterbalance weight has a radial outer surface, and the counterbalance weight is positioned above the radial outer gripping surface such that the radial outer surface of the counterbalance weight is substantially contiguous with the radial outer gripping surface of the lower hand grip portion.   
     
     
         25 . The wedge-type golf club of  claim 24 , wherein the counterbalance weight increases in diameter from a lower end of the counterbalance weight to an upper end of the counterbalance weight. 
     
     
         26 . The wedge-type golf club of  claim 24 , wherein the upper hand grip portion extends at least partially over the upper end of the shaft, and the counterbalance weight extends at least partially over an upper end of the upper hand grip portion.