Golf club

Abstract

A golf club head includes a club body including a crown, a sole, a skirt disposed between and connecting the crown and the sole and a face portion connected to a front end of the club body. The face portion includes a geometric center defining the origin of a coordinate system when the golf club head is ideally positioned, the coordinate system including an x-axis being tangent to the face portion at the origin and parallel to a ground plane, a y-axis intersecting the origin being parallel to the ground plane and orthogonal to the x-axis, and a z-axis intersecting the origin being orthogonal to both the x-axis and the y-axis. The golf club head defines a center of gravity CG, the CG being a distance CGY from the origin as measured along the y-axis and a distance CGZ from the origin as measured along the z-axis.

1 . A golf club head comprising:
 a club body including a leading edge, a trailing edge, a crown, a sole, and a skirt disposed between and connecting the crown and the sole;   an adjustable head-shaft connection assembly coupled to the club body and operable to adjust at least one of a loft angle or a lie angle of a golf club formed when the golf club head is attached to a golf club shaft via the head-shaft connection assembly;   at least one external mass element that is adjustably attachable to the club body; and   a face portion connected to a front end of the club body, the face portion including a geometric center defining the origin of a coordinate system when the golf club head is ideally positioned, the coordinate system including:   an x-axis being tangent to the face portion at the origin and parallel to a ground plane,   a y-axis intersecting the origin being parallel to the ground plane and orthogonal to the x-axis, and   a z-axis intersecting the origin being orthogonal to both the x-axis and the y-axis;   the golf club head defining a center of gravity (CG), the CG being a distance CG Y  from the origin as measured along the y-axis and a distance CG Z  from the origin as measured along the z-axis;   wherein the golf club head has a moment of inertia (I XX ) about a CG x-axis, the CG x-axis being parallel to the x-axis and passing through the CG of the golf club head;   wherein there is a face-to-crown transition where the face connects to the crown near the front end of the club body and a skirt-to-crown transition where the skirt connects to the crown;   wherein in a y-z plane passing through the origin the crown height continuously increases starting from the face-to-crown transition up to a local maximum;   wherein in a y-z plane passing through the origin at a distance CG Y  from the origin the crown height is greater than the face height;   wherein in a y-z plane passing through the origin the skirt-to-crown transition proximate the trailing edge is lower than the origin;   wherein in a y-z plane passing through the origin the skirt-to-crown transition proximate the trailing edge is higher than the center of gravity;   wherein a CG effectiveness product (CG eff ) for the golf club head is defined as
   CG eff =CG Y ×Δ z ;
 
   and the CG eff  is at least 806 mm 2 .   
     
     
         2 . The golf club head of  claim 1  further including a sole feature protruding from the sole and extending from a central mid-portion of the sole to the trailing edge, whereby the sole feature adds additional mass to the sole to lower the CG of the club head. 
     
     
         3 . The golf club head of  claim 2  wherein the sole feature adds about 5 to 15 cm 3  of volume to the club head. 
     
     
         4 . The golf club head of  claim 2  wherein the sole feature has a generally flat rear edge at the trailing edge. 
     
     
         5 . The golf club head of  claim 1  further including a sole bulge feature protruding from the sole and extending from a central mid-portion of the sole to the trailing edge, the sole bulge feature forming a generally flat raised surface on the sole and having opposed shoulders on either side of the raised surface. 
     
     
         6 . The golf club head of  claim 5  wherein the sole bulge feature adds about 5 to 15 cm 3  of volume to the club head. 
     
     
         7 . The golf club head of  claim 1  wherein the at least one external mass element includes a first weight attached to a sole portion of the club body forward of the CG and a second weight attached to the sole portion rearwardly of the CG, and wherein the first weight has a first mass and the second weight has a second mass and the second mass is at least double the first mass. 
     
     
         8 . The golf club head of  claim 1  wherein the club head has a crown height to face height ratio of at least 1.12. 
     
     
         9 . The golf club head of  claim 1  wherein the CG is located at least −3.3 mm below the origin. 
     
     
         10 . The golf club head of  claim 1  wherein I xx  is at least 350 Kg·mm 2 . 
     
     
         11 . The golf club head of  claim 7 , wherein at least one of the first weight and the second weight is formed of a greater density material than the club body. 
     
     
         12 . The golf club head of  claim 11 , wherein at least one of the first weight and the second weight is formed of a tungsten material. 
     
     
         13 . The golf club head of  claim 12 , wherein at least a portion of the club body is formed of a titanium material. 
     
     
         14 . The golf club head of  claim 13 , further comprising a sole feature located at a rearward portion of the golf club head that extends from the sole downward towards the ground plane; wherein the sole feature comprising a first side wall located at least partially heel-ward of the sole feature, a second side wall located at least partially toe-ward of the sole feature, and a lower sole feature surface extending from the first side wall to the second side wall, wherein the lower sole feature surface is the lowest portion of the golf club head that is located rearward of the center of gravity. 
     
     
         15 . The golf club head of  claim 14 , wherein a volume of the golf club head is at least 430 cc. 
     
     
         16 . The golf club head of  claim 15 , wherein the CG is located a distance ΔZ from the ground plane that is no more than 24.6 mm. 
     
     
         17 . A golf club head comprising:
 a club body including a leading edge, a trailing edge, a crown, a sole, and a skirt disposed between and connecting the crown and the sole;   at least one external mass element that is adjustably attachable to the club body; and   a face portion connected to a front end of the club body, the face portion including a geometric center defining the origin of a coordinate system when the golf club head is ideally positioned, the coordinate system including:   an x-axis being tangent to the face portion at the origin and parallel to a ground plane,   a y-axis intersecting the origin being parallel to the ground plane and orthogonal to the x-axis, and   a z-axis intersecting the origin being orthogonal to both the x-axis and the y-axis;   the golf club head defining a center of gravity (CG) located at least −3.3 mm below the origin, the CG being a distance CG Y  from the origin as measured along the y-axis and a distance CG Z  from the origin as measured along the z-axis;   wherein the golf club head has a moment of inertia (I XX ) about a CG x-axis, the CG x-axis being parallel to the x-axis and passing through the CG of the golf club head;   wherein there is a face-to-crown transition where the face connects to the crown near the front end of the club body and a skirt-to-crown transition where the skirt connects to the crown;   a sole feature protruding from the sole to add mass to the sole and extending from a central mid-portion of the sole to the trailing edge, the sole feature having opposed shoulders which extend rearwardly and terminate proximate to the trailing edge;   an adjustable head-shaft connection assembly coupled to the club body and operable to adjust at least one of a loft angle or a lie angle of a golf club formed when the golf club head is attached to a golf club shaft via the head-shaft connection assembly, a first external weight element located on the sole forward of the CG and a second external weight element located in the sole rearward of the CG;   wherein the club head has a I xx  of at least 350 Kg·mm 2 ;   wherein the CG is located to least −3.3 mm below the origin.   
     
     
         18 . The golf club head of  claim 11  further including an adjustable head-shaft connection assembly coupled to the club body and operable to adjust at least one of a loft angle or a lie angle of a golf club formed when the golf club head is attached to a golf club shaft via the head-shaft connection assembly, a first external weight element located on the sole forward of the CG and a second external weight element located in the sole rearward of the CG. 
     
     
         19 . The golf club head of  claim 11  wherein the club head has a I xx  of at least 350 Kg·mm 2 . 
     
     
         20 . A golf club head comprising:
 a club body including a leading edge, a trailing edge, a crown, a sole and a skirt disposed between and connecting the sole and crown;   a face portion connected to a front end of the club body, the face portion including a geometric center defining the origin of a coordinate system when the golf club head is ideally positioned, the coordinate system including:   an x-axis being tangent to the face portion at the origin and parallel to a ground plane,   a y-axis intersecting the origin being parallel to the ground plane and orthogonal to the x-axis, and   a z-axis intersecting the origin being orthogonal to both the x-axis and the y-axis;   the golf club head defining a center of gravity (CG), the CG being a distance CG Y  from the origin as measured along the y-axis and a distance CG Z  from the origin as measured along the z-axis;   a sole bulge feature protruding from the sole away from the crown and extending rearwardly from a central mid-portion of the sole to the trailing edge, the sole feature adding additional mass to the sole to lower the CG of the club body, the sole bulge feature forming a raised surface on the sole and having opposed shoulders on either side of the raised surface, the opposed shoulders terminating proximate to the trailing edge, the sole bulge feature having a rear edge which joins the opposed shoulders along the trailing edge;   at least two external weights supported on the sole, one being located forward of the CG and the other rearward of the CG;   wherein the CG is located at least −3.3 mm below the origin and I xx  is at least 350 Kg·mm 2 ;   wherein a volume of the golf club head is at least 430 cm 3 ;   wherein at least one of the first weight and the second weight is formed of a greater density material than the club body;   wherein the first weight has a first mass and the second weight has a second mass and the second mass is at least double the first mass;   wherein at least a portion of the club body is formed of a titanium material.