| 摘要 |
<p>PURPOSE:To manufacture a golf club shaft having less localized wall thickness and higher strength than a conventional shaft by forming the prescribed thickness of a thermoplastic resin layer on the surface of a mandrel via an injection molding method, winding prepreg around the surface of the layer, and setting the mandrel so made in a shaft forming die for formation under pressure and heat. CONSTITUTION:A mandrel 1 is set in an injection die 5 and this die 5 is filled with a thermoplastic resin via the resin filling hole 51 thereof. The resin is cooled under pressure, thereby forming a thermoplastic resin layer 2 on the mandrel 1. In this case, the thickness of the layer is between 0.8mm and 2.0mm. Then, prepreg 3 is wound around the layer so formed, and set in a shaft forming die 4. Furthermore, the mandrel is supplied with a compressed fluid from the hollow section thereof, and the fluid is blown through a compressed fluid discharge hole 11, thereby heating and forming the prepreg 3 under the application of internal pressure. According to this construction, a golf club shaft can be manufactured remarkably efficiently, compared with a conventional club.</p> |
