Piston with crown cooling cavity and radial ribs formed therein

摘要

A piston for an internal combustion engine formed as an integrally cast article having a crown portion and a hollow cylindrical side wall portion, wherein the crown portion is formed with a transverse hollow space, radially outside portions of which are axially traversed by integrally formed ribs, the hollow space being adapted to be circulated by lubricant for the purpose of cooling the crown portion. To supply lubricant into and to drain lubricant from the hollow space, a transverse wall portion formed in the crown portion on the inner side of the hollow space is formed with a lubricant inlet opening and at least one lubricant outlet opening, preferably at portions located between the ribs.