| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a golf club shaft having superior carry performance and ball hitting directivity. <P>SOLUTION: Points obtained by plotting flexural rigidities E1 measured at ten points on a shaft are defined as T(1) to T(10) in this order from the head side and an expression of a straight line K passing through T(1) and T(10) is defined as [Y=aX+b1]. Values of Y-intercept of straight lines being in parallel to the straight line K and passing through points T(2) to T(9) are defined as b2 to b9 respectively, and the minimum value of the values b2 to b9 of the Y-intercepts is defined as bmin. The gradient (a) of the straight line K is not less than 0.04 and not more than 0.06, all of b3, b4, b5, b6, b7 and b8 are smaller than b1, bmin is either one of b4 to b7, (b1-bmin) is not less than 30_(N m<SP>2</SP>) and not more than 40_(N m<SP>2</SP>), and (b9-bmin) is not less than 4 and not more than 15_(N m<SP>2</SP>). This shaft has a high-strength straight layer and a hoop layer. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
