Patent ID: 7210448

Claim:
An internal combustion engine containing a combustion chamber, comprising; an engine body including an engine cylinder, a cylinder head forming an inner face of the combustion chamber and at least one intake port formed in the cylinder head for directing intake air into the combustion chamber; a piston positioned for reciprocal movement in said engine cylinder between a bottom dead center position and a top dead center position, said piston including a piston crown including a top face facing the combustion chamber, said piston crown containing a piston bowl formed by an outwardly opening cavity, said piston bowl including a projecting portion having a distal end, an inner bowl floor section extending inwardly, an outwardly flared outer bowl section having a concave curvilinear shape in cross section, and a chamfer extending toward said top face at an angle δ in the range of 30 to 75 degrees from an axis of reciprocation of the piston; and an injector mounted on the engine body adjacent said projecting portion of said piston bowl to inject fuel into the combustion chamber, said injector including a plurality of orifices arranged to form a spray plume; wherein the intake air undergoes a swirling effect during operation to provide a swirl ratio in the range of 0.5–2.5.