Molding method of connector portion

A molding method of a connector portion, which includes (i) an electric wire with a core wire covered with an insulating coating made of a synthetic resin such that a tip of the core wire projects from the insulating coating, (ii) a terminal metal fitting electrically joined to the core wire projecting from the insulating coating, and (iii) a mold portion made of a synthetic resin disposed on both the electric wire and the terminal metal fitting to enclose a joining portion between the core wire and the terminal metal fitting, and covering the joining portion,

• the molding method of insert-molding the mold portion with a plurality of molding dies forming a cavity corresponding to the mold portion, the method comprising:
• an injection step of inserting the electric wire with the core wire covered with the insulating coating into the cavity and closing the plurality of molding dies so that the insulating coating is compressed and deformed, and injecting and filling a mold resin, as the synthetic resin material of the mold portion, into the cavity;
• and
• a mold opening step of separating each molding die of the plurality of molding dies in a mold opening direction while the mold resin has fluidity so that leakage of the mold resin is prevented by an elastic return pressure of the insulating coating.