| 摘要 |
<p>PURPOSE:To improve controllability in the case of hitting a ball at an end part on the yoke part side of a gut surface, and improve repulsive property in the case of hitting the ball at a center part or on the top part side. CONSTITUTION:A boundary line is set at a position of 2/5 of the whole length L in a Y-direction of the longer axis of a gut surface is set along the Y- direction of the longer axis from an end part 4a on the side of a yoke part 2b of the gut surface toward the top part side. A range surrounded by the end part 4a on the yoke part 2b side and the boundary line is a first range A1. A range of 3/5 of the whole length L of the Y-direction of the longer axis of the gut surface from the boundary line toward the top part 2c side along the Y-direction of the longer axis is a second range A2. A ratio between an average value of length in the longer axis Y-direction of mesh M formed by intersections of guts in the longer axis Y-direction and guts in the shorter axis direction in the first range A1, and an average value of length in the longer axis Y-direction of the mesh M in the second range A2 is set to be 0.3 or more and 1.0 or less.</p> |
