Approaching to the internal peripheral surface of the bobbin in the peripheral face of production of the bobbin in the electrodynamic type valve Drive

摘要

PROBLEM TO BE SOLVED: To reduce an inertia mass of a valve system by lightening a weight of a bobbin of an electrodynamic valve driving device. SOLUTION: After a woven fabric 20 made of reinforcing fiber is wound around an outer peripheral surface of a cylindrical mandrel 21, thermosetting resin is impregnated or coated on its surface, and the thermosetting resin is heated and hardened so as to form the bobbin 19.