| 摘要 |
<p>PURPOSE:To improve the repulsion performance of the tennis racket frame. CONSTITUTION:The rigidity of the tennis racket frame 1, i.e., the ratio of the rigidity in the inside direction of a ball fitting face F and the rigidity in the outside direction of the ball fitting face F and the ratio of the rigidity in the warp direction within the ball fitting face F and the rigidity in the weft direction are so set as to increase a repulsion coefft. A sweet area S is moved upward from heretofore to allow the effective action of the rotating speed of the frame 1, by which the repulsion performance is improved.</p> |
