Golf club head with sole rails

1. A golf club head that, when oriented in a reference position, comprises:

a striking face;

a top portion; and

a sole portion opposite the top portion, the sole portion comprising (i) a leading edge, (ii) a trailing edge, (iii) at least three sole rails each generally elongate in a front-to-rear direction and including a central sole rail, a heel-side sole rail, and a toe-side sole rail, (iv) a sole contact point located on the central sole rail, (v) a first recess formed between the central sole rail and the toe-side sole rail, and (vi) a second recess formed between the central sole rail and the heel-side sole rail;

wherein, in a virtual vertical plane extending in the front-to-rear direction and passing through the sole contact point:

the sole portion includes a sole length Ls measured in the front-to-rear direction from the leading edge to the trailing edge;

the sole contact point is spaced rearwardly from the leading edge by a distance D 1 no greater than 0.8*Ls, D1 also being between 5 mm and 15 mm; and

the sole portion comprises (i) a plurality of radii of curvature that each extend in the front-to-rear direction and are forward of the sole contact point, a radius of curvature of the plurality of radii of curvature closest to the leading edge being spaced rearward from the leading edge by less than distance D 1 and by no more than 3 mm, and (ii) at least one radius of curvature that extends in the front-to-rear direction and is rearward of the sole contact point;

wherein, in the reference position and along the virtual vertical plane, a vertical distance between the sole portion and a virtual ground plane increases forward of the sole contact point from the sole contact point to the leading edge;

wherein the central sole rail extends closer to the leading edge than do the heel-side and toe-side sole rails;

wherein the central sole rail comprises a forward end, a rearward end, and a width in a heel-to-toe direction that varies such that a minimum central sole rail width corresponds with a location intermediate the forward end and the rearward end, the location being closer to the forward end than to the rearward end, and the location being between 10% and 25% of the sole length Ls from the leading edge; and

wherein a distance between heel-side and toe-side walls of each of the first and second recesses increases continuously from a forward-most part of the recess to a rearward-most part of the recess.

2. The golf club head of claim 1 , further comprising a loft between 14 degrees and 26 degrees.

3. The golf club head of claim 1 , wherein the sole length Ls is no less than 35 mm.

4. The golf club head of claim 1 , wherein D 1 is no greater than 0.5*Ls.

5. The golf club head of claim 4 , wherein D 1 is no greater than 0.25*Ls.

6. The golf club head of claim 1 , wherein:

the striking face further comprises a face center; and

the central sole rail is generally aligned with the face center in the heel-to-toe direction.

7. The golf club head of claim 1 , wherein, in the virtual vertical plane, the leading edge comprises a height H 1 no less than 5 mm.

8. The golf club head of claim 1 , wherein the at least central sole rail includes an elevation no less than 3 mm.

9. A golf club head that, when oriented in a reference position, comprises:

a striking face;

a top portion; and

a sole portion opposite the top portion, the sole portion comprising (i) a leading edge, (ii) a trailing edge, (iii) three sole rails each generally elongate in a front-to-rear direction and including a central sole rail, a heel-side sole rail, and a toe-side sole rail, (iv) a sole contact point located on the central sole rail, (v) a first recess formed between the first central sole rail and the toe-side sole rail, the first recess having a step-down portion defined in the front-to-rear direction, and (vi) a second recess formed between the central sole rail and the heel-side sole rail;

wherein, in a virtual vertical plane extending in the front-to-rear direction and passing through the sole contact point:

the sole portion includes a sole length Ls measured in the front-to-rear direction from the leading edge to the trailing edge;

the sole contact point is spaced rearwardly from the leading edge by a distance D 1 no greater than 0.8*Ls, D 1 also being between 5 mm and 15 mm; and

the sole portion comprises (i) a plurality of radii of curvature that each extend in the front-to-rear direction and are forward of the sole contact point, a radius of curvature of the plurality of radii of curvature closest to the leading edge being spaced rearward from the leading edge by less than distance D 1 and by no more than 3 mm, and (ii) at least one radius of curvature that extends in the front-to-rear direction and is rearward of the sole contact point;

wherein, in the reference position and along the virtual vertical plane, a vertical distance between the sole portion and a virtual ground plane increases forward of the sole contact point from the sole contact point to the leading edge; wherein the central sole rail extends closer to the leading edge than do the heel-side and toe-side sole rails;

wherein the central sole rail comprises a forward end, a rearward end, and a width in a heel-to-toe direction that varies such that a minimum central sole rail width corresponds with a location intermediate the forward end and the rearward end, the location being closer to the forward end than to the rearward end, and the location being between 10% and 25% of the sole length Ls from the leading edge; and

wherein a distance between heel-side and toe-side walls of each of the first and second recesses increases continuously from a forward-most part of the recess to a rearward-most part of the recess.

10. The golf club head of claim 9 , wherein the step-down portion comprises a depth no less than 2 mm.

11. The golf club head of claim 9 , wherein:

the first and second recesses each further comprise a bottom surface and a side surface, which includes the heel-side and toe-side walls and at least partially circumscribes the bottom surface; and

the central sole rail is elevated from the bottom surface of each of the first and second recesses by a distance no less than 3 mm.

12. The golf club head of claim 9 , further wherein:

the striking face further comprises a face center; and

the central sole rail is generally aligned with the face center in a-the heel-to-toe direction.

13. The golf club head of claim 9 , wherein, in the virtual vertical plane extending in the front-to-rear direction and passing through the sole contact point, the leading edge comprises a height H 1 no less than 5 mm.

14. A golf club head that, when oriented in a reference position, comprises:

a striking face;

a top portion; and

a sole portion opposite the top portion, the sole portion comprising (i) a leading edge, (ii) a trailing edge, (iii) at least three sole rails each generally elongate in a front-to-rear direction and including a central sole rail, a heel-side sole rail, and a toe-side sole rail, (iv) a sole contact point located on the central sole rail, (v) a first recess formed between the central sole rail and the toe-side sole rail, and (vi) a second recess formed between the central sole rail and the heel-side sole rail;

wherein, in a virtual vertical plane extending in the front-to-rear direction and passing through the sole contact point:

the leading edge includes a height H 1 of no less than 5 mm;

the sole further comprises a first radius of curvature R 1 at a first location spaced rearward from the leading edge by no more than 3 mm and a second radius of curvature R 2 at a second location rearward of the first location, the second radius of curvature R 2 being forward of the sole contact point;

R 2 is no less than 10*R 1 ; and

R 2 is no less than 100 mm;

wherein, in the virtual vertical plane and relative to an interior of the golf club head, the sole portion is not convex from the leading edge to the trailing edge;

wherein the central sole rail extends closer to the leading edge than do the heel-side and toe-side sole rails;

wherein the central sole rail comprises a forward end, a rearward end, and a width in a heel-to-toe direction that varies such that a minimum central sole rail width corresponds with a location intermediate the forward end and the rearward end, the location being closer to the forward end than to the rearward end, and the location being between 10% and 25% of the sole length Ls from the leading edge; and

wherein a distance between heel-side and toe-side walls of each of the first and second recesses increases continuously from a forward-most part of the recess to a rearward-most part of the recess.

15. The golf club head of claim 14 , wherein R 1 is no greater than 30 mm.

16. The golf club head of claim 14 , wherein:

the striking face further comprises a face center; and

the central sole rail is generally aligned with the face center in a-the heel-to-toe direction.