PURPOSE: To prevent the resonance and to form the said arm pipe light in weight and high in Young's modulus, by molding the core pipe made of shield tube winding and coating carbon long fibers with synthetic resin.
CONSTITUTION: The shield tube 1 formed with fine wires of copper or aluminum is inserted to the core shaft, and after the carbon long fiber 2 coated with the bonding agent such as epoxy resin is wound on the external circumference of the tube 1, this is entered the molding metal mold. It is heated at around 150°C temperature to form the core pipe by bonding the tube 1 and the fiber 2. Next, synthetic resin such as ABS resin is pressed and poured in the clearance among the core shaft, core pipe and metal mold, the assembly is incorporated in the state that the core pipe is inserted between the synthetic resins 3 and 4 to form the tone arm pipe.
OONISHI JIYUNICHI
NISHIKAWA KAZUO
