| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a golf club head where a back spin quantity of a hit ball can be increased sufficiently. <P>SOLUTION: On the face surface 3 of the golf club head, two or more lines of corrugations 4 and two or more cutting marks made by milling work are constituted. The cutting marks 5 are shaped like S where a toe side compared with the center of the face surface 2 is in the state of an upward-projecting arc with a curvature radius of about 80 to 120 mm, and a heel side is in the state of a downward-projecting arc with a curvature radius of about 80 to 120 mm. As shown in the figure, the cutting marks 5 are continued from the toe side to the heel side. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
