Caterpillar Inc.
PISTON FOR INTERNAL COMBUSTION ENGINE HAVING VALVE POCKET STEP FOR SLOWING COMBUSTION GAS FLOW

Abstract:

A piston for an internal combustion engine includes a plurality of valve pockets formed in a piston rim, the valve pockets forming fluid flow paths through the piston rim. Each of the valve pockets includes a central step standing proud of a pocket floor to limit a fluid flow area through the pocket and slow combustion gas flow from a combustion bowl toward a cylinder liner and thereby reduce displacement of an engine oil film thereon.