Golf club and golf club head structures

1. A golf club head comprising:

a body defining a ball striking face, a crown, and a sole,

the body further having a first leg extending away from the ball striking face and a second leg extending away from the ball striking face,

wherein a void is defined between the first leg and the second leg,

the crown extending over the void,

the body further defines an internal cavity defined at least in part by an inner surface of the ball striking face, an underside surface of the crown, and an internal surface of the sole, and a first wall having a first inner surface facing into the internal cavity and a first outer surface facing into the void, and a second wall having a second inner surface facing into the internal cavity and a second outer surface facing into the void; and

wherein the first wall and the second wall have respective distal ends and wherein the distal ends extend toward one another,

wherein a center of gravity of the golf club head is located within the internal cavity.

2. The golf club head of claim 1 , wherein the first leg and the second leg converge towards one another to an interface area,

the interface area positioned proximate a central location of the club head.

3. The golf club head of claim 2 , wherein the interface area defines a third wall having a third inner surface facing into the internal cavity and a third outer surface facing into the void, wherein the third wall is substantially vertical.

4. The golf club head of claim 2 , wherein the club head defines a breadth dimension and the interface area is positioned at a range of 40%-60% of the breadth dimension, measured from the ball striking face.

5. The golf club head of claim 1 , wherein a moment of inertia through a center of gravity of the golf club head about a vertical axis is in a range between 4300 g*cm 2 and 5200 g*cm 2 .

6. The golf club head of claim 1 , wherein the void is not visible at an address position, and wherein the void is visible from an underside of the club head.

7. The golf club head of claim 1 , further comprising

a first gusset member positioned proximate the first inner surface of the first wall, and

wherein the first gusset member has a first side connected proximate the first inner surface of the first wall and a second side connected on an internal sole surface,

and

further comprising a second gusset member positioned proximate the second inner surface of the second wall,

wherein the second gusset member has a first side connected proximate the second inner surface of the second wall and a second side connected on the internal sole surface.

8. The golf club head of claim 1 , wherein the internal cavity defines a first volume and wherein the void defines a second volume,

wherein the second volume of the void is approximately 15%-25% of the first volume of the internal cavity.

9. A golf club head comprising:

a body defining a ball striking face, a crown and a sole,

the body further having a first leg extending away from the ball striking face and a second leg extending away from the ball striking face

wherein a void is defined between the first leg and the second leg,

the crown extending over the void,

the body further defining an internal cavity defined at least in part by an inner surface of the ball striking face, an underside surface of the crown, and an internal surface of the sole,

the first leg having a first wall having an first inner surface facing into the internal cavity and a first outer surface facing into the void, the second leg having a second wall having a second inner surface facing into the internal cavity and a second outer surface facing into the void;

and wherein the first leg and the second leg converge towards one another to an interface area,

wherein the body defines a rear and wherein the void has a first width proximate the interface area and a second width proximate the rear, the second width being greater than the first width;

wherein the internal cavity defines a first volume and wherein the void defines a second volume,

wherein the second volume of the void is approximately 15%-25% of the first volume of the internal cavity; and

wherein the golf club head has a third volume in a range between 430 cc and 460 cc.

10. The golf club head of claim 9 , wherein the void is not visible at an address position, and wherein the void is visible from an underside of the club head.

11. The golf club head of claim 9 , further comprising

a first gusset member positioned proximate the first inner surface of the first wall, and

wherein the first gusset member has a first side connected proximate the first inner surface of the first wall and a second side connected on an internal sole surface, and

further comprising a second gusset member positioned proximate the second inner surface of the second wall,

wherein the second gusset member has a first side connected proximate the second inner surface of the second wall and a second side connected on the internal sole surface.

12. The golf club head of claim 9 , wherein the first wall and the second wall have respective distal ends and wherein the distal ends extend toward one another.

13. The golf club head of claim 9 , wherein the club head defines a breadth dimension and the interface area is positioned at a range of 40%-60% of the breadth dimension, measured from the ball striking face.

14. The golf club head of claim 9 , wherein a center of gravity of the club head is located within the internal cavity.

15. The golf club head of claim 9 , wherein the golf club head has a first natural frequency, other than six rigid body modes, is in a range between 2750 Hz and 3200 Hz.

16. The golf club of claim 9 , wherein the first wall and the second wall have respective distal ends and wherein the distal ends extend toward one another.

17. A golf club head comprising:

a body defining a ball striking face, a crown and a sole, the body further having a first leg extending away from the ball striking face and a second leg extending away from the ball striking face

wherein a void is defined between the first leg and the second leg, the crown extending over the void,

the body further defining an internal cavity defined at least in part by an inner surface of the ball striking face, an underside surface of the crown, and an internal surface of the sole, the first leg having a first wall having an first inner surface facing into the internal cavity and a first outer surface facing into the void, the second leg having a second wall having a second inner surface facing into the internal cavity and a second outer surface facing into the void;

wherein the first leg and the second leg converge towards one another to an interface area,

wherein the interface area defines a substantially vertically oriented third wall having a third inner surface facing into the internal cavity and a third outer surface facing into the void; and

wherein a moment of inertia through a center of gravity of the golf club head about a vertical axis is in a range between 4300 g*cm2 and 5200 g*cm2.

18. The golf club head of claim 17 , wherein the club head defines a breadth dimension and the interface area is positioned at a range of 40%-60% of the breadth dimension, measured from the ball striking face.

19. The golf club head of claim 17 , wherein the void is not visible at an address position, and wherein the void is visible from an underside of the club head.