Golf club head and method of manufacturing the same

Abstract

A method comprising, in a striking face of a golf club head, the striking face being formed of a first material having a first hardness, creating a plurality of initial grooves, the initial grooves having a first cross-sectional area (A 1 ) and a first pitch (P 1 ) such that A 1 /P 1 >0.0030 in. The method continues with modifying the initial grooves at least by positioning a second material in each of the plurality of initial grooves, the second material having a second hardness that is less than the first hardness, such that the first material and the second material form a plurality of final grooves each having a second cross-sectional area (A 2 ) and a second pitch (P 2 ) such that A 2 /P 2 <0.0030 in.

We claim: 
     
         1 . A golf club head comprising:
 a toe portion;   a heel portion opposite the toe portion;   a sole portion;   a top portion opposite the sole portion;   a rear portion;   a striking face that defines a striking face plane and includes a plurality of grooves that extend substantially in a heel to toe direction, each of the grooves comprising:
 a pair of sidewalls that extends away from the striking face plane, at least one of the pair of sidewalls having an undercut portion distal to the striking face plane; and 
 a resilient member located at least partially in the undercut portion; and 
   a loft no less than 25 degrees.   
     
     
         2 . The golf club head of  claim 1 , wherein the pair of sidewalls comprises a first material and the resilient member comprises a second material that is softer than the first material. 
     
     
         3 . The golf club head of  claim 2 , wherein the first material is metallic and the second material is selected from the group consisting of: a polymer, a foam, a rubber, and a resin. 
     
     
         4 . The golf club head of  claim 2 , wherein the second material contrasts in appearance from the first material. 
     
     
         5 . The golf club head of  claim 1 , wherein each of the sidewalls has an undercut portion. 
     
     
         6 . The golf club head of  claim 5 , wherein the sidewalls substantially mirror each other. 
     
     
         7 . The golf club head of  claim 1 , wherein each of the grooves has a depth from the striking face plane to the resilient member less than 0.020 in. and a width less than 0.035 in. 
     
     
         8 . The golf club head of  claim 1 , wherein each of the grooves includes an entry hole. 
     
     
         9 . The golf club head of  claim 1 , wherein the resilient member has a thickness between 0.009 inch and 0.025 inch. 
     
     
         10 . The golf club head of  claim 1 , wherein each of the grooves has an effective radius of between 0.009 inch and 0.011 inch. 
     
     
         11 . The golf club head of  claim 1 , wherein the resilient member entirely fills the undercut portion. 
     
     
         12 . A golf club head comprising:
 a toe portion;   a heel portion opposite the toe portion;   a sole portion;   a top portion opposite the sole portion;   a rear portion;   a striking face that defines a striking face plane and includes a plurality of grooves that extend substantially in a heel to toe direction, each of the grooves comprising:
 a pair of sidewalls that extends away from the striking face plane, at least one of the pair of sidewalls having an undercut portion distal to the striking face plane; and 
 an insert located in the undercut portion; 
   a plurality of final grooves each delimited by the sidewalls and the insert of each of the grooves such that the final groove has a bottom surface formed by the insert; and   a loft no less than 25 degrees.   
     
     
         13 . The golf club head of  claim 12 , wherein the pair of sidewalls comprises a first material and the insert comprises a second material that is softer than the first material. 
     
     
         14 . The golf club head of  claim 13 , wherein the first material is metallic and the second material is selected from the group consisting of: a polymer, a foam, a rubber, and a resin. 
     
     
         15 . The golf club head of  claim 12 , wherein each of the sidewalls has an undercut portion. 
     
     
         16 . The golf club head of  claim 15 , wherein the sidewalls substantially mirror each other. 
     
     
         17 . The golf club head of  claim 12 , wherein each of the grooves has a depth from the striking face plane to the insert less than 0.020 in. and a width less than 0.035 in. 
     
     
         18 . The golf club head of  claim 12 , wherein each of the grooves includes an entry hole. 
     
     
         19 . The golf club head of  claim 12 , wherein the insert has a thickness between 0.009 inch and 0.025 inch. 
     
     
         20 . The golf club head of  claim 12 , wherein each of the grooves has an effective radius of between 0.009 inch and 0.011 inch.