High loft, low center-of-gravity golf club heads

Abstract

A golf club and golf club head having a high static loft angle, low forward center of gravity, and enhanced z-axis gear effect via a large roll radius and/or tightly controlled moment of inertia about the CG x-axis, Ixx, associated with upward and downward twisting of the club head.

1 .- 20 . (canceled) 
     
     
         21 . A golf club head, comprising:
 a club head body having an external surface with a heel portion, a toe portion, a crown portion, a sole portion, a skirt portion positioned around a periphery between the sole portion and crown portion, a ball striking face having a thickness, and a hosel integrally formed with the club head body and extending outward from the club head body proximate to a crown and heel transition region;   wherein the ball striking face of the club head body has a geometric center;   wherein the crown portion has one or more openings, and wherein one or more corresponding crown panels are placed in the one or more openings, the one or more crown panels having a first material density and a first portion thickness no more than 1.5 mm;   wherein a portion of the club head body located below a geometric center of the ball striking face is formed of a second material having a second material density and a second portion thickness, wherein the second material density is at least twice the first material density of the one or more crown panels;   wherein a moment of inertia about a golf club head center-of-gravity x-axis, Ixx, is between 250-800 kg−mm 2 ;   wherein the golf club head has a club head volume of at least 250 cm 3  and a club head weight of between about 190 and 210 grams;   wherein the one or more crown panels are held in place by adhesive bonding;   wherein the ball striking face has a variable face thickness that is no more than 5 mm, the face thickness is greater than the first portion thickness, and at least a portion of the face thickness is at least twice the first portion thickness;   wherein the golf club head has a center of gravity that is below the geometric center of the ball striking face of the golf club head as measured along a z-axis of the golf club head having an origin at the geometric center;   wherein at least a portion of the golf club head is formed of a fiber reinforced plastic; and   wherein the ball striking face has a roll radius less than 300 mm and greater than 100 mm.   
     
     
         22 . The golf club head of  claim 21 , wherein the sole portion is at least partially formed of a material that is denser than the material used to form the crown portion, and at least a portion of the crown portion is held in place by adhesive bonding. 
     
     
         23 . The golf club head of  claim 22 , wherein the golf club head has a Delta 1 between 10 to 25 mm. 
     
     
         24 . The golf club head of  claim 23 , wherein the club head volume is at least 460 cm 3  or greater. 
     
     
         25 . The golf club head of  claim 23 , wherein the center of gravity is 5-20 mm below the geometric center of the ball striking face of the golf club head as measured along a z-axis of the golf club head having an origin at the geometric center. 
     
     
         26 . The golf club head of  claim 22 , wherein the golf club head has an origin at the geometric center of the ball striking face and a projection of the center of gravity onto the ball striking face is located off-center from the geometric center in a direction toeward of the origin. 
     
     
         27 . The golf club head of  claim 21 , wherein at least a portion of the crown portion, the sole portion, and the skirt portion are held in place by adhesive bonding. 
     
     
         28 . The golf club head of  claim 27 , wherein the club head body is formed from a combination of an alloy of aluminum and a composite material. 
     
     
         29 . The golf club head of  claim 28 , wherein at least a portion of the ball striking face is held in place by adhesive bonding. 
     
     
         30 . The golf club head of  claim 29 , wherein at least a portion of the ball striking face comprising a ball striking surface is formed of a composite material. 
     
     
         31 . The golf club head of  claim 27 , wherein the golf club head has a Delta 1 between 10 to 25 mm. 
     
     
         32 . The golf club head of  claim 31 , wherein the club head volume is at least 460 cm 3  or greater. 
     
     
         33 . The golf club head of  claim 27  wherein the center of gravity is 5-20 mm below the geometric center of the ball striking face of the golf club head as measured along a z-axis of the golf club head having an origin at the geometric center. 
     
     
         34 . The golf club head of  claim 21 , wherein the golf club head has an origin at the geometric center of the ball striking face and a projection of the center of gravity onto the ball striking face is located off-center from the geometric center in a direction toeward of the origin. 
     
     
         35 . The golf club head of  claim 21 , wherein a projection of the center of gravity onto the ball striking face of the club head body is located off-center from the geometric center in a direction toward the sole portion, and the golf club head has a Delta 1 between 10 to 25 mm. 
     
     
         36 . A golf club head, comprising:
 a club head body having an external surface with a heel portion, a toe portion, a crown portion, a sole portion, a skirt portion positioned around a periphery between the sole portion and crown portion, a ball striking face having a thickness, and a hosel integrally formed with the club head body and extending outward from the club head body proximate to a crown and heel transition region;   wherein the crown portion has one or more openings, and wherein one or more corresponding crown panels are placed in the one or more openings, the one or more crown panels having a first material density and a first portion thickness;   wherein a portion of the club head body located below a geometric center of the ball striking face is formed of a second material having a second material density and a second portion thickness, wherein the second material density is at least twice the first material density of the one or more crown panels;   wherein a moment of inertia about a golf club head center-of-gravity x-axis, Ixx, is between 250-800 kg−mm 2 ;   wherein the golf club head has a club head volume of at least 250 cm 3  and a club head weight of between about 190 and 210 grams;   wherein at least a portion of the crown portion, the sole portion, the skirt portion, and the ball striking face are held in place by adhesive bonding;   wherein the ball striking face has a varying thickness no more than 5 mm and no less than 2.5 mm; and   wherein the golf club head has a center of gravity that is below the geometric center of the ball striking face of the golf club head as measured along a z-axis of the golf club head having an origin at the geometric center; and   wherein at least a portion of the club head body comprises an alloy of aluminum.   
     
     
         37 . The golf club head of  claim 36 , wherein the golf club head comprises one or more locations configured to receive one or more weights. 
     
     
         38 . The golf club head of  claim 37 , wherein the ball striking face having a roll radius less than 300 mm and greater than 100 mm. 
     
     
         39 . The golf club head of  claim 38 , wherein the ball striking face has a varying thickness no more than 5 mm and no less than 2.5 mm. 
     
     
         40 . The golf club head of  claim 38 , wherein the golf club head has a Delta 1 between 10 mm to 25 mm. 
     
     
         41 . The golf club head of  claim 40 , wherein the center of gravity is 5-20 mm below the geometric center of the ball striking face of the golf club head as measured along a z-axis of the golf club head having an origin at the geometric center. 
     
     
         42 . The golf club head of  claim 38 , wherein the club head body is formed from a combination of materials and components and further comprises an alloy of steel, and a fiber reinforced plastic. 
     
     
         43 . The golf club head of  claim 38 , wherein the club head body is formed from a combination of materials and components and further comprises an alloy of titanium, and a fiber reinforced plastic.