Golf club having a low modulus crown

Abstract

According to some examples, a golf club head includes a sole positioned on a bottom side of the golf club head; a striking face positioned toward a front of the golf club head and attached to at least a portion of the sole; a crown positioned on a top side of the golf club head and including: a crown opening; a recessed ledge around the crown opening; and a crown insert engaging the recessed ledge and including at least about 85% of an exterior surface area of the crown, wherein the recessed ledge is made of a first material and the crown insert is made of a second material, the second material displaying an elastic modulus of about 10 GPa to about 50 GPa, and wherein a density of the second material is less than a density of the first material.

1 . A golf club head comprising:
 a sole positioned on a bottom side of the golf club head;   a striking face positioned toward a front of the golf club head and attached to at least a portion of the sole;   a crown positioned on a top side of the golf club head and comprising:
 a crown opening; 
 a recessed ledge around the crown opening; and 
 a crown insert engaging the recessed ledge and comprising at least about 85% of an exterior surface area of the crown, 
   wherein the recessed ledge is made of a first material and the crown insert is made of a second material, the second material displaying an elastic modulus of about 10 GPa to about 50 GPa, and   wherein a density of the second material is less than a density of the first material.   
     
     
         2 . The golf club head of  claim 1 , wherein the first material is titanium and the second material is a magnesium-based material. 
     
     
         3 . The golf club head of  claim 1 , wherein the crown insert is formed from a polyphenylene sulfide (PPS) material and a composite material. 
     
     
         4 . The golf club head of  claim 3 , wherein the PPS material comprises at least about 90% of a volume of the crown insert. 
     
     
         5 . The golf club head of  claim 1 , wherein the second material includes one of a glass fiber reinforced plastic or a Kevlar fiber reinforced plastic. 
     
     
         6 . The golf club head of  claim 1 , wherein an offset distance between the striking face and the crown insert is between about 10 mm to about 20 mm. 
     
     
         7 . A golf club head comprising:
 a sole positioned on a bottom side of the golf club head;   a striking face positioned toward a front of the golf club head and attached to at least a portion of the sole; and   a crown positioned on a top side of the golf club head and comprising:
 a crown opening, 
 a perimeter outer portion that comprises a recessed ledge around the crown opening, and 
 a crown insert engaging the recessed ledge and comprising at least about 85% of an exterior surface area of the crown, 
   wherein the perimeter outer portion is made of a first material and the crown insert is made of a second material, and   wherein a thickness of the perimeter outer portion is greater than a thickness of the crown insert.   
     
     
         8 . The golf club head of  claim 7 , wherein the second material includes one of a glass fiber reinforced plastic or a Kevlar fiber reinforced plastic. 
     
     
         9 . The golf club head of  claim 7 , wherein the crown insert is formed from a polyphenylene sulfide (PPS) material and a composite material. 
     
     
         10 . The golf club head of  claim 7 , wherein the second material displays an elastic modulus of about 10 GPa to about 50 GPa. 
     
     
         11 . The golf club head of  claim 7 , wherein the thickness of the crown insert is 0.4-0.6 mm. 
     
     
         12 . The golf club head of  claim 7 , wherein the thickness of the perimeter outer portion is between about 0.4 and about 1.0 mm thick. 
     
     
         13 . The golf club head of  claim 7 , wherein a ratio of the thickness of the crown insert to the thickness of the perimeter outer portion is about 1:2. 
     
     
         14 . The golf club head of  claim 7 , wherein a ratio of the thickness of the crown insert to the thickness of the perimeter outer portion is about 2:3. 
     
     
         15 . The golf club head of  claim 7 , wherein an offset distance between the striking face and the crown insert is between about 10 mm to about 20 mm. 
     
     
         16 . A golf club head comprising:
 a sole positioned on a bottom side of the golf club head;   a striking face positioned toward a front of the golf club head and attached to at least a portion of the sole; and   a crown positioned on a top side of the golf club head and comprising:
 a crown opening, 
 a recessed ledge around the crown opening, and 
 a crown insert engaging the recessed ledge and covering the crown opening, 
   wherein the recessed ledge is made of a first material and the crown insert is made of a second material, the second material displaying an elastic modulus of about 10 GPa to about 50 GPa.   
     
     
         17 . The golf club head of  claim 16 , wherein the first material is titanium and the second material is a magnesium-based material. 
     
     
         18 . The golf club head of  claim 16 , wherein the second material displays an elastic modulus of between about 10 GPa to about 20 GPa. 
     
     
         19 . The golf club head of  claim 16 , wherein the crown insert is formed from a polyphenylene sulfide (PPS) material and a composite material. 
     
     
         20 . The golf club head of  claim 19 , wherein the PPS material comprises at least about 90% of a volume of the crown insert.