| 摘要 |
PURPOSE: To reduce the ball striking vibration ill-influencing a hand palm to a great extent by furnishing a buffer part in the frame of a tennis racket, installing a buffer layer of gal-form substance in this buffer part in such a way as enwrapped by a core layer made of a foamable synthetic resin, and thereby allowing the buffer layer and core layer to dispersively absorb the impact given at the time of striking a ball. CONSTITUTION: A buffer part 30 is provided in the two-pronged part 121 of a grip shank 12 and the top and crosswise frame pieces 112 of a ring-shaped frame part 11 and is composed of a core layer 31 made of foamable synthetic resin formed in the hard skeleton of the frame 10 of tennis racket and a buffer layer 32 made of gel-form substance buried in the core layer 31. When a ball is struck, the impact vibration which is received to a netting surface 111 is transmitted to the palm through the racket frame 10. Because the impact vibration is passed through the buffer part 30, only the remaining portion after being damped by the buffer layer 32 is transmitted to the palm. The gel-form substance forming the buffer layer 32 assumes a non-elastic deformation, and does not generate a repulsive resilience and propagates to a wide area quickly, so that the vibration is absorbed dampedly over the whole gel-form substance, and the residue nevertheless transmitted to the palm is of very low level and can be converged in a short time. |
