MOLD STRUCTURE FOR MOLDING CYLINDRICAL MEMBER

PROBLEM TO BE SOLVED: To provide a mold structure for molding a cylindrical member to prevent a core mold from being bent or deformed, and to manufacture the cylindrical member with high precision.SOLUTION: The mold structure for molding a cylindrical member includes a cylindrical cavity mold, and a rod-like core mold 10 inserted and mounted in an inner hole of the cavity mold to form an injection space between the core mold 10 and itself, to mold the cylindrical member by injecting a molten resin in the injection space. A plurality of projections 19 each protruding from the tip end 10b of the core mold 10 to the outside in the direction of the axial line O2 are arranged spaced apart from each other in the circumferential direction of the center of the axial line O2 on the tip end 10b side of the core mold 10. The core mold 10 is inserted and mounted in the inner hole of the cavity mold. A plurality of the projections 19 are brought into contact with the inner surface of the cavity mold to position and support the tip end 10b side of the core mold 10.