Patent ID: 8211266

Claim:
A badminton racket manufacturing method comprising: a resin sheet tube forming process that forms a resin sheet tube by placing an expandable resin that expands when heated on an inner side of a thermoplastic resin sheet and rolling the thermoplastic resin sheet into a cylindrical shape; an expandable resin placing process that places an expandable resin that expands when heated on an outer periphery of a portion of a joint, the joint being to be installed to reach inside a frame formed with the resin sheet tube and inside a shaft, the portion being to be installed in the frame; and a joining process that joins the frame and the shaft by installing the joint placed with the expandable resin inside both end portions of the resin sheet tube, bent circularly and butted against each other, and the shaft, and setting the frame, the shaft and the joint in a die, and then heating the frame, the shaft and the joint, and spreading out the both end portions along the die by the expandable resin placed on the joint, wherein in the joining process, a pushing of the resin sheet tube against the die with the expandable resin in the resin sheet tube, and a pushing of the both end portions of the resin sheet tube against the die with the expandable resin on the joint are performed substantially simultaneously.