GOLF CLUB HEAD

• US 20110021289A1
• Filed: 07/21/2010
• Published: 01/27/2011
• Est. Priority Date: 07/22/2009
• Status: Active Grant

• Current Assignee: Sumitomo Rubber Industries Limited
• Original Assignee: Dunlop Sports Co. Ltd. (Sumitomo Rubber Industries Limited)
• Inventors: YOKOTA, Masatoshi
• Granted Patent: US 8,591,354 B2
• Time in Patent Office: Days
• US Class Current: 473/346
• CPC Class Codes: A63B 2209/00 Characteristics of used materials
• CPC Class Codes: A63B 53/0408 characterised by specific dimensions, e.g. thickness
• CPC Class Codes: A63B 53/0416 Heads having an impact surface provided by a face insert
• CPC Class Codes: A63B 53/0433 with special sole configurations
• CPC Class Codes: A63B 53/045 Strengthening ribs
• CPC Class Codes: A63B 53/0466 wood-type
• CPC Class Codes: A63B 53/047 iron-type
• CPC Class Codes: A63B 53/0475 with one or more enclosed cavities

Abstract

When a length of a cross section CS1 in a face-back direction is defined as L; a point being 0.1 L from a forefront point Mz2 of the cross section and positioned on an outer surface of the sole is defined as Ma; a point being 0.2 L from a backmost point Mk2 of the cross section and positioned on the outer surface of the sole is defined as Md; intersection points of lines and the outer surface of the sole are defined as a point Mb and a point Mc from a face side in order, the lines equally dividing a distance between the point Ma and the point Md into three in the face-back direction; a distance of a cross section CS2 in the toe-heel direction is defined as W; intersection points of lines and the outer surface of the sole are defined as a point Mp, a point Mq, and a point Mr from a toe side in order, the lines equally dividing the distance W into four in the toe-heel direction; a radius of a circle passing through the point Ma, the point Mb, and the point Mc is defined as Ra; a radius of a circle passing through the point Mb, the point Mc, and the point Md is defined as Rb; and a radius of a circle passing through the point Mp, the point Mq, and the point Mr is defined as Rc, Ra>Rb>Rc is satisfied.

Claims

1. A golf club head comprising a face, a crown, and a sole,

wherein when a length of a cross section CS1 in a face-back direction is defined as L, the cross section CS1 positioned at a center position in a toe-heel direction;

a point being 0.1 L from a forefront point of the cross section in the face-back direction and positioned on an outer surface of the sole is defined as Ma;

a point being 0.2 L from a backmost point of the cross section in the face-back direction and positioned on the outer surface of the sole is defined as Md;

intersection points of lines and the outer surface of the sole are defined as a point Mb and a point Mc from a face side in order, the lines equally dividing a distance between the point Ma and the point Md into three in the face-back direction;

a distance of a cross section CS2 in the toe-heel direction is defined as W, the cross section CS2 being 20 mm from a forefront point of the head and being parallel to the toe-heel direction;

intersection points of lines and the outer surface of the sole are defined as a point Mp, a point Mq, and a point Mr from a toe side in order, the lines equally dividing the distance W into four in the toe-heel direction;

a radius of a circle passing through the point Ma, the point Mb, and the point Mc is defined as Ra;

a radius of a circle passing through the point Mb, the point Mc, and the point Md is defined as Rb; and

a radius of a circle passing through the point Mp, the point Mq, and the point Mr is defined as Rc,

the radius Ra is greater than the radius Rb, and the radius Rb is greater than the radius Rc.

2. The golf club head according to claim 1, wherein the radius Ra is equal to or greater than 250 (mm);

the radius Rb is equal to or less than 200 (mm); and

the radius Rc is equal to or less than 130 (mm).

3. The golf club head according to claim 1, wherein a rib is provided on an inner surface of the sole.

4. The golf club head according to claim 1, wherein when a point at which a minute section curvature radius Rs1 is minimal between the point Mc and the point Md in the cross section CS1 is defined as Me, the point Me is positioned on a back side from the point Mc.

5. The golf club head according to claim 1, wherein when a point at which a minute section curvature radius Rs1 is minimal between the point Mc and the point Md in the cross section CS1 is defined as Me, the sole has a projection part positioned on a back side from the point Me.

6. The golf club head according to claim 1, wherein a ratio [Ra/Rb] is equal to or greater than 3;

a ratio [Rb/Rc] is 1.1 or greater and 3 or less; and

a ratio [Ra/Rc] is equal to or greater than 4.

7. The golf club head according to claim 3, wherein when an angle between an extending direction of the rib and the toe-heel direction is θ

1 (degree), an absolute value of the angle θ

1 is equal to or less than 20 degrees.

8. The golf club head according to claim 3, wherein when an angle between an extending direction of the rib and the face-back direction is θ

2 (degree), an absolute value of the angle θ

2 is equal to or less than 20 degrees.

9. The golf club head according to claim 1, wherein when a minute section curvature radius Rs2 is defined in all cross sections parallel to the cross section CS2, the minute section curvature radius Rs2 is 50 mm or greater and 300 mm or less at all positions of the outer surface of the sole.

10. The golf club head according to claim 3, wherein a first rib is provided so that the absolute value of the angle θ

1 with respect to the toe-heel direction is equal to or less than 20 degrees, and a second rib is provided so that the absolute value of the angle θ

2 with respect to the face-back direction is equal to or less than 20 degrees.

11. The golf club head according to claim 1, wherein the distance W is 100 mm or greater and less than 127 mm.

12. The golf club head according to claim 1, wherein a volume of the head is 400 cc or greater and 470 cc or less.

13. The golf club head according to claim 3, wherein a rib height Hr of the rib is 1 mm or greater and 10 mm or less.

14. The golf club head according to claim 3, wherein a rib width Wr of the rib is 0.5 mm or greater and 10 mm or less.

15. The golf club head according to claim 1, wherein when a point at which a minute section curvature radius Rs1 is minimal between the point Mc and the point Md in the cross section CS1 is defined as Me;

a point positioned on the cross section CS1 and being L/2 (mm) from the forefront point Mz2 of the cross section in the face-back direction is defined as a sole central point Sc; and

a distance between the sole central point Sc and the point Me in the face-back direction is defined as De (mm), the distance De is −

20 (mm) or greater and +10 mm or less, the distance De represented by plus (+) when the point Me is positioned on a back side from the point Sc and represented by minus (−

) when the point Me is positioned on a face side from the point Sc.