Golf club heads with a multi-material striking surface

Abstract

Embodiments of putter-type golf club head comprising a striking surface capable of achieving consistent ball speeds across the striking surface to account for various ball impact locations are described herein. The striking surface has at least two materials that differs in concentration away from the geometric center of the striking surface to provide this consistency. Consistent (or uniform) ball speed is achieved throughout the striking surface as the portion of the golf ball that contacts the striking surface interacts with at least two materials having a differing material characteristic.

1 . A putter-type golf club head comprising:
 a body comprising:
 a heel portion; 
 a toe portion distal from the heel portion; 
 a top rail; 
 a sole portion distal from the top rail; and 
 a striking surface forming a recess defined by the heel portion, the toe portion, the top rail, and the sole portion of the body; 
   a striking surface imaginary vertical axis that extends through a geometric center of the striking surface relative to the heel portion, the toe portion, the top rail, and the sole portion; and   an insert configured to be received within and complimentary with the recess defined by the striking surface;
 wherein: 
 the insert comprises a front surface adapted to impact a golf ball and a rear surface opposite the front surface, and a thickness defined as the distance between the front surface and the rear surface; 
 the insert comprises a first material forming the rear surface and a second material forming a portion of the front surface; 
 the insert further defines a plurality of concentric radiating voids that extends throughout the entirety of the second material putter insert thickness; 
 each of the concentric radiating voids has a common center at the geometric center, 
   wherein the striking surface comprises an upper border and a lower border;   wherein a majority of concentric radiating voids are connected to both the upper border and the lower border of the striking surface;   wherein a first concentric radiating void does not connect to either the upper border or lower border of the striking surface, and a second concentric radiating void is connected to the upper border or the lower border; and   wherein a strut connects the first concentric radiating void and the second concentric radiating void; and   each of the concentric radiating voids is arranged to increase in diameter outwardly and away from the geometric center.   
     
     
         2 . The putter type golf club head of  claim 1 , wherein the first material comprises a first hardness and the second material comprises a second hardness. 
     
     
         3 . The putter type golf club head of  claim 1 , wherein the first material comprises a polymer that at least partially fills the plurality of concentric radiating voids, and the second material comprises a metal. 
     
     
         4 . The putter type golf club head of  claim 1 , wherein densities of the first material and the second material are substantially the same. 
     
     
         5 . The putter type golf club head of  claim 1 , wherein each of the strut or string of struts are recessed inward from the front surface of the striking surface. 
     
     
         6 . The putter type golf club head of  claim 1 , wherein each of the strut or string of struts connects one or more concentric radiating voids. 
     
     
         7 . The putter type golf club head of  claim 1 , wherein the putter type golf club head comprises a loft angle less than 7 degrees. 
     
     
         8 . The putter type golf club head of  claim 1 , wherein each of the concentric radiating voids extends vertically in a top rail-to-sole direction and connect to both an upper border of the striking surface and a lower border of the striking surface. 
     
     
         9 . The putter type golf club head of  claim 1 , wherein at the front surface of the insert, the second material surrounds the first material. 
     
     
         10 . The putter type golf club head of  claim 1 , wherein the combination of the first material and the second material has a constant overall thickness.