METHOD FOR MOLDING SYNTHETIC RESIN PISTON

摘要

PROBLEM TO BE SOLVED: To secure dimensional precision by preventing the contraction of a resin at places where dimensional precision is particularly required and to prevent the generation of voids and cracks. SOLUTION: A method for molding a synthetic resin piston is constituted by packing a resin from a resin injection hole 1d in a mold 1 for molding the piston which has a hole 1d on the extended line of the axis of the piston and rod-shaped projections 1e, 1f perpendicular to the axis.