| 摘要 |
PROBLEM TO BE SOLVED: To provide a racket frame which is lightweight, satisfies intended characteristics of a racket frame such as torsion, bending strength, flexural rigidity, and compressive strength and compressive rigidity in the internal direction of the space, and is stable in quality. SOLUTION: A racket frame having a shell layer 6 made by laminating an FRP layer 7 wherein the inner layer of the shell layer 6 and an intermediate layer are composed of biaxial blades 8a, 8b which are formed in a manner of having an angle of inclination opposing to each other with respect to the axes. In the outer layer, a partially triaxial blade 12 where a circumferential axis 10 is concentrated on the circumference is arranged in the axes 9a, 9b of reinforcing fibers to be knitted biaxially so that the circumferential axis 10 may be positioned in the periphery 13 of the frame which is orthogonal to the gut surface of the racket frame. |
