| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a golf club head which keeps the strength of a face part and suppresses the repellence of a face center within a range adapting to rules while keeping weight reduction of the face part, and which delivers uniform repellence performance even when hitting a ball if it is separated from a face center. <P>SOLUTION: The face portion 11 of the golf club head is provided with first to fourth main ribs 12 to 15 on the inner surface of the head. The first main rib 12 extends from the center portion 18 of the face part to the crown side, and the second main rib 13 extends from the center portion 18 to the sole side. The thickness of the face portion 11 is formed so as to be thin in the order of the center portion 18, the first main rib 12, and the second main rib 13. The third and fourth main ribs 14 and 15 extend from the center portion 18 in outward directions of the face portion 11. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
