| 摘要 |
PROBLEM TO BE SOLVED: To lighten weight and heighten rebounding performance for tennis racket. SOLUTION: The racket frame is set that the weight is 200g>=, 140g<=, the balance, which is the distance from grip end to the center of gravity, is 280 mm<=, 400 mm>=, the ratio of the stiffness (top pressure stiffness) of in-plane direction of top part of face part 3 that surrounds the ball hitting face to the stiffness (ball hitting face stiffness) of outof-plane direction of face part (top pressure stiffness/ball hitting face stiffness) is 0.7>, 0.25<=, and the ratio of the stiffness (ball hitting face stiffness) of out-of-plane direction of face part to the stiffness of throat part 4 (ball hitting face stiffness/throat part stiffness) is 0.3<=, 0.8>=. |
