PISTON OF INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To provide a piston of an internal combustion engine, capable of suppressing the occurrence of knocking before and after the top dead center.SOLUTION: A piston 10 of an internal combustion engine slides in a cylinder 14, and includes: a recess 33 formed on a top face of a head 31; and an engaging member engaging with the recess. The engaging member can operate in a sliding direction of the piston so that an engagement state with the recess changes before and after the top dead center. The engaging member includes: a cover 34 having a shape corresponding to the recess; a through hole 36 provided on the cover; a support shaft 35 penetrating the through hole; and an enlarged diameter part 37 provided at a tip of the support shaft and having a diameter larger than an inner diameter of the through hole.