Patent ID: 8146563

Claim:
An internal combustion engine comprising: a cylinder block having at least one cylinder for receiving a piston; a cylindrical piston reciprocable within said cylinder in response to a combustion event involving air and an injected fuel quantity from an injector providing fuel injection from a central location in a radiated, substantially non-swirl pattern; a fuel injector injecting fuel into said combustion chamber in a measured and timed quantity; said piston having a crown formed on the end thereof facing said combustion chamber, the crown having an annular recess with a central axis substantially coaxial with the central location for said injector and a internal central crown portion forming an angle with respect to the central axis that between 0 percent and 5 percent of the angle with which fuel is injected into said combustion chamber and a substantially curved outer portion directing air compressed by said piston around the curve and toward said central axis to mix with and be directed along said peak by said fuel and wherein the outer diameter of the opening to said annular recess is no greater than 40% of the diameter of said piston.