| 摘要 |
PROBLEM TO BE SOLVED: To enhance the rigidity of a shaft part of a racket frame and to improve a swinging-through property by embedding a metallic pipe or strip-like reinforcing plate into at least the shaft part and mounting a weight member having a specific gravity higher than the specific gravity of a fiber reinforced resin at a face part. SOLUTION: The tube 1A of the racket frame for tennis consists of the face part 1a, the shaft part 1c and a grip part 1d. After a prepreg is disposed on the outer periphery of the tube 1A, the reinforcing plate 5 made of a βtitanium alloy is so disposed as to extend from the flank at the top end of the grip part 1d through the shaft part 1c to the rear end of the face part 1a. The reinforcing plate 5 is further covered by the prepreg and then the tube 1A is expanded and heated in a metal mold to cure the prepreg. The prepreg is subjected to deflashing after parting from the mold, by which a racket frame product is obtained. As a result, adequate strength and rigidity are imparted to the racket frame and the durability to repetitive fatigue is improved. |
