GOLF CLUB HEAD

• US 20080125243A1
• Filed: 11/16/2007
• Published: 05/29/2008
• Est. Priority Date: 11/28/2006
• Status: Active Grant

• Current Assignee: Bridgestone Sports Co Limited (Bridgestone Corporation)
• Original Assignee: Bridgestone Sports Co Limited (Bridgestone Corporation)
• Inventors: Ban, Wataru
• Granted Patent: US 7,674,188 B2
• Time in Patent Office: Days
• US Class Current: 473/331
• CPC Class Codes: A63B 53/0408 characterised by specific dimensions, e.g. thickness
• CPC Class Codes: A63B 53/0445 Details of grooves or the like on the impact surface
• CPC Class Codes: A63B 53/0466 wood-type
• CPC Class Codes: A63B 53/047 iron-type

Abstract

A golf club head of this invention includes a face, a plurality of score line grooves formed on the face, and traces formed in the face by milling. Edges of the score line grooves are rounded with a radius of not more than 0.2 mm. A width W (mm) of the score line groove measured with the rounded edge being included, a width Ws (mm) between the score line grooves adjacent to one another, a width Wr (mm) of the score line groove measured based on the 30 degrees measurement rule and a cross section area S (mm²) of the score line grooves satisfy the flowing expressions; W/Ws×100≧35(%) and S/(Wr×0.5)×100≧70(%). The face in which the traces are formed has the arithmetic mean deviation of the profile (Ra) of not less than 4.00 μm.

Claims

1. A golf club head comprising:

a face;

a plurality of score line grooves formed on the face; and

traces formed in the face by milling,

wherein edges of the score line grooves are rounded with a radius of not more than 0.2 mm,

a width W (mm) of the score line groove measured with the rounded edge being included, a width Ws (mm) between the score line grooves adjacent to one another, a width Wr (mm) of the score line groove measured based on the 30 degrees measurement rule and a cross section area S (mm²) of the score line grooves satisfy the flowing expressions;

W/Ws×

100≧

35(%) and

S/(Wr×

0.5)×

100≧

70(%), and

the face in which the traces are formed has the arithmetic mean deviation of the profile (Ra) of not less than 4.00 μ

m.

2. The golf club head according to claim 1, wherein the face in which the traces are formed has the arithmetic mean deviation of the profile (Ra) of between 4.00 μ

m and 4.57 μ

m, inclusive.

3. The golf club head according to claim 1, wherein

the traces are a plurality of striations, and

an angle formed by an arrangement direction of the plurality of striations and the score line groove is between 40 degrees and 70 degrees, inclusive, as viewed clockwise from a toe side end of the score line groove.

4. The golf club head according to claim 3, wherein

each striation forms a circular arc, and

the arrangement direction is a direction that intersects the center of the circular arc of each striation.

5. The golf club head according to claim 1, wherein the width Wr is not less than 0.6 mm and not more than 0.9 mm.