Wood-type golf club head

• US 7,857,713 B2
• Filed: 09/05/2007
• Issued: 12/28/2010
• Est. Priority Date: 10/19/2006
• Status: Active Grant

• Current Assignee: Sumitomo Rubber Industries Limited
• Original Assignee: SRI Sports Limited (Sumitomo Rubber Industries Limited)
• Inventors: Yokota, Masatoshi
• Primary Examiner(s): Hunter; Alvin A
• Application Number:
  US11/896,759
• Publication Number:
  US 20080096688A1
• Time in Patent Office: 1,210 Days
• Field of Search: 473324-350
• US Class Current: 473/345
• CPC Class Codes: A63B 2053/0491 with added weights, e.g. changeable, replaceable
• CPC Class Codes: A63B 53/0408 characterised by specific dimensions, e.g. thickness
• CPC Class Codes: A63B 53/0412 Volume
• CPC Class Codes: A63B 53/0416 Heads having an impact surface provided by a face insert
• CPC Class Codes: A63B 53/042 the face insert consisting of a material different from that of the head
• CPC Class Codes: A63B 53/0433 with special sole configurations
• CPC Class Codes: A63B 53/0437 with special crown configurations
• CPC Class Codes: A63B 53/0458 with non-uniform thickness of the impact face plate
• CPC Class Codes: A63B 53/0462 characterised by tapering thickness of the impact face plate
• CPC Class Codes: A63B 53/0466 wood-type
• CPC Class Codes: A63B 60/02 Ballast means for adjusting the centre of mass A63B60/24, A63B60/54 take precedence

Abstract

A hollow wood-type golf club head 1 having a volume of 420 to 500 cm³ and comprising face portion 3, wherein the face portion 3 comprises a metallic material having a specific gravity of 4.30 to 4.60 and has a thickness of 1.5 to 4.0 mm, and in the standard state of head 1, the X/Y ratio is 0.0070 or less in which X is the depth (mm) of the club head'"'"'s center of gravity which is a horizontal length between the center of gravity and a sweet spot on face 2 in the front-rear direction of head 1, and Y is the moment of inertia (g·cm²) of head 1 about the vertical axis passing through the center of gravity, and the intersection line of the face 2 with a horizontal plane including the sweet spot is convex toward the front of head 1 and has a radius of curvature of 330.2 to 457.2 mm.

Claims

1. A hollow wood-type golf club head having a head volume of 420 to 500 cm³, and comprising a face portion having a hitting face for hitting a golf ball on a front side and a sole portion extending from the lower edge of the hitting face and forming a bottom surface of the club head, wherein:

said face portion is made of a metallic material having a specific gravity of 4.30 to 4.60 and has a thickness of 1.5 to 4.0 mm,

in a standard state that the club head is placed on a horizontal plane at prescribed lie and loft angles, an X/Y ratio is 0.0070 or less in which X is a depth (mm) of the center of gravity of the club head which is a horizontal length between the center of gravity and a sweet spot on said hitting face in a front-rear direction of the club head, and Y is a moment of inertia (g·

cm²) of the club head about the vertical axis passing through the center of gravity,

said hitting face is convexly curved such that an intersection line of said hitting face and a horizontal plane including the sweet spot is convex toward the front of the club head, and a radius of curvature Rc of said intersection line is from 330.2 to 457.2 mm, and a radius of curvature on a heel side portion of the intersection line is larger than each of radii of curvature of a middle portion and a toe side portion of the intersection line by at least 12.7 mm,

said sole portion is provided with a toe side weight member Wt disposed on a toe side and a heel side weight member Wh disposed on a heel side, and the center of gravity of each of the weight members Wt and Wh is located on a front side of the center of gravity of the club head, and

said club head comprising a head body and a face member which constitutes a main part of said face portion and is fixed to said head body, in which said face member is made of a first titanium alloy having a Young'"'"'s modulus of 120 to 150 GPa and said head body is made of a second titanium alloy having a larger specific gravity than that of said first titanium alloy.

2. The golf club head of claim 1, wherein a face progression which is a horizontal length in the front-rear direction in the standard state of the club head from a vertical plane VP for determining said lie angle to a farthest leading edge of said hitting face, is from 10 to 22 mm.

3. The golf club head of claim 1, wherein the radius of curvature on a heel side of said intersection line is larger than the radius of curvature on a toe side of said intersection line.

4. The golf club head of claim 1, wherein said first titanium alloy has a tensile strength of 950 to 2,200 MPa.

5. The golf club head of claim 1, wherein said first titanium alloy comprises 4.5 to 5.5% by weight of aluminum, 0.5 to 1.5% by weight of iron, and the rest of titanium and unavoidable impurities.

6. The golf club head of claim 1, wherein each of the weight members Wt and Wh has a specific gravity of at least 7.0, and said second titanium alloy has a specific gravity of at most 4.51.

7. A hollow wood-type golf club head having a head volume of 420 to 500 cm³, and comprising a face portion having a hitting face for hitting a golf ball on a front side and a sole portion extending from the lower edge of the hitting face and forming a bottom surface of the club head, wherein:

said face portion is made of a metallic material having a specific gravity of 4.30 to 4.60 and has a thickness of 1.5 to 4.0 mm,

in a standard state that the club head is placed on a horizontal plane at prescribed lie and loft angles, an X/Y ratio is 0.0070 or less in which X is a depth (mm) of the center of gravity of the club head which is a horizontal length between the center of gravity and a sweet spot on said hitting face in a front-rear direction of the club head, and Y is a moment of inertia (g·

cm²) of the club head about the vertical axis passing through the center of gravity,

said hitting face is convexly curved such that an intersection line of said hitting face and a horizontal plane including the sweet spot is convex toward the front of the club head, a radius of curvature Rc of said intersection line is from 330.2 to 457.2 mm, and a radius of curvature on a heel side portion of said intersection line is larger than each of radii of curvature of a middle portion and a toe side portion of said intersection line by at least 12.7 mm, and

said sole portion is provided with a toe side weight member Wt disposed on a toe side and a heel side weight member Wh disposed on a heel side, and the center of gravity of each of the weight members Wt and Wh is located on a front side of the center of gravity of the club head.

8. The golf club head of claim 7, wherein a face progression which is a horizontal length in the front-rear direction in the standard state of the club head from a vertical plane VP for determining said lie angle to a farthest leading edge of said hitting face, is from 10 to 22 mm.

9. The golf club head of claim 7, wherein the radius of curvature on a heel side of said intersection line is larger than the radius of curvature on a toe side of said intersection line.

10. The golf club head of claim 7, wherein said club head comprises a head body and a face member which constitutes a main part of said face portion and is fixed to said head body, in which said face member is made of a first titanium alloy having a Young'"'"'s modulus of 120 to 150 GPa and said head body is made of a second titanium alloy having a larger specific gravity than that of said first titanium alloy.

11. The golf club head of claim 10, wherein said first titanium alloy has a tensile strength of 950 to 2,200 MPa.

12. The golf club head of claim 10, wherein said first titanium alloy comprises 4.5 to 5.5% by weight of aluminum, 0.5 to 1.5% by weight of iron, and the rest of titanium and unavoidable impurities.

13. The golf club head of claim 10, wherein each of the weight members Wt and Wh has a specific gravity of at least 7.0, and said second titanium alloy has a specific gravity of at most 4.51.

14. A hollow wood-type golf club head having a head volume of 420 to 500 cm³, and comprising a face portion having a hitting face for hitting a golf ball on a front side and a sole portion extending from the lower edge of the hitting face and forming a bottom surface of the club head, wherein:

said face portion is made of a metallic material having a specific gravity of 4.30 to 4.60 and has a thickness of 1.5 to 4.0 mm,

in a standard state that the club head is placed on a horizontal plane at prescribed lie and loft angles, an X/Y ratio is 0.0070 or less in which X is a depth (mm) of the center of gravity of the club head which is a horizontal length between the center of gravity and a sweet spot on said hitting face in a front-rear direction of the club head, and Y is a moment of inertia (g·

cm²) of the club head about the vertical axis passing through the center of gravity, and

said hitting face is convexly curved such that an intersection line of said hitting face and a horizontal plane including the sweet spot is convex toward the front of the club head, a radius of curvature Rc of said intersection line is from 330.2 to 457.2 mm, and a radius of curvature on a heel side portion of said intersection line is larger than each of radii of curvature of a middle portion and a toe side portion of said intersection line by at least 12.7 mm.

15. The golf club head of claim 14, wherein a face progression which is a horizontal length in the front-rear direction in the standard state of the club head from a vertical plane VP for determining said lie angle to a farthest leading edge of said hitting face, is from 10 to 22 mm.

16. The golf club head of claim 14, wherein the radius of curvature on a heel side of said intersection line is larger than the radius of curvature on a toe side of said intersection line.

17. The golf club head of claim 14, wherein said first titanium alloy has a Young'"'"'s modulus of 120 to 150 GPa and a tensile strength of 950 to 2,200 MPa.

18. The golf club head of claim 17, wherein said second titanium alloy has a Young'"'"'s modulus of 100 to 120 GPa and a tensile strength of 900 to 1,200 MPa, and a ratio e1/e2 of the Young'"'"'s modulus e1 of said first titanium alloy to the Young'"'"'s modulus e2 of said second titanium alloy is from 1.0 to 1.50.

19. The golf club head of claim 17, wherein said second titanium alloy has a Young'"'"'s modulus of 100 to 120 GPa and a tensile strength of 900 to 1,200 MPa, and a ratio S1/S2 of the tensile strength S1 of said first titanium alloy to the tensile strength S2 of said second titanium alloy is from 1.05 to 1.35.

20. The golf club head of claim 14, wherein said first titanium alloy comprises 4.5 to 5.5% by weight of aluminum, 0.5 to 1.5% by weight of iron, and the rest of titanium and unavoidable impurities.

21. The golf club head of claim 14, wherein said second titanium alloy has a specific gravity of at most 4.51.

22. The golf club head of claim 14, wherein a ratio sg1/sg2 of a specific gravity sg1 of said first titanium alloy to a specific gravity sg2 of said second titanium alloy is 0.95 or more.

23. The golf club head of claim 14, wherein said second titanium alloy has a Young'"'"'s modulus of 100 to 120 GPa and a tensile strength of 900 to 1,200 MPa.

24. The golf club head of claim 14 , wherein said first titanium alloy is a Ti—

Al—

Fe alloy.

25. The golf club head of claim 14, wherein said first titanium alloy is Ti-5Al-1Fe alloy.

26. The golf club head of claim 25, wherein said second titanium alloy is a member selected from the group consisting of Ti-6Al-4V, Ti-3Al-2.5V, Ti-4.5Al-2Mo-1.6V-0.5Fe-0.3Si-0.03C, Ti-4.5Al-4Cr-0.5Fe-0.2C, Ti-4.5Al-2Cr-1Mo-1.3V-0.5Fe-0.15C, Ti-4.5Al-3V -2Fe-2Mo, Ti-1Fe-0.35O, Ti-5Al-2Fe-3Mo, and Ti-6Al-1Fe.

27. The golf club head of claim 14, which has a depth of the center of gravity of 23 to 27 mm.

28. The golf club head of claim 14, wherein said club head comprises a head body and a face member which constitutes a main part of said face portion and is fixed to said head body, in which said face member is made of a first titanium alloy and said head body is made of a second titanium alloy having a larger specific gravity than that of said first titanium alloy.