Patent ID: 8047935

Claim:
A rectangular sporting pipe, comprising: a shaft; and at least two bulging portions formed on a surface portion of a corner of the shaft, the bulging portions extending in a longitudinal direction of the shaft and bulging outwardly, wherein the shaft comprises a plurality of prepreg sheets wound around entirely, said prepreg sheets being formed by impregnating a reinforcing fiber with a resin, wherein the bulging portions and a side surface of the shaft are formed integrally by the plurality of prepreg sheets, wherein each of the bulging portions projects outwardly from the side surface of the shaft, wherein a part of the bulging portions adjacent to the side surface extends outwardly at an angle with a plane of the side surface of the shaft, and wherein an angle between an outer prepreg at a border of the side surface and a corresponding one of the bulging portions is smaller than that of an inner prepreg.