MOLD FOR INJECTION MOLDING

摘要

PROBLEM TO BE SOLVED: To improve the shape accuracy of a cylindrical molding. SOLUTION: The mold for injection molding comprises a recess 47 for forming an outer surface of a tapered part 41b of a cylinder 41 on an inner surface 47a in a fixed mold 2 of the mold for forming a cavity 3 for forming the cylinder 41 having the tapered part 41b at one end of a cylindrical part 41a. The mold further comprises a hole 49 for forming an outer peripheral surface of the cylindrical part 41a of the cylinder 41 on the inner peripheral surface 49a of a movable mold 48 being the other mold. The mold further comprises a core 50 having a tapered distal end 5 at one end of a core body 4 of a columnar shape inserted in the hole 49 and toward the fixed mold 2. The mold comprises the outer peripheral surface 50a of the body 4 forming the outer peripheral surface of the cylinder 41a and the distal end face 50b of the distal end 5 forming the inner surface of the tapered part 41b. The mold further comprises gates G with a plurality of valves B for injecting the material M opened at the position of the radial inside from the outer peripheral surface 50a of the core 50 on the inner surface 47a of the recess 47 of the fixed mold 2. COPYRIGHT: (C)2003,JPO