Direct cylinder injection-type spark ignition internal combustion engine

摘要

A direct cylinder injection-type spark ignition internal combustion engine is disclosed. The engine comprises a spark plug, a cavity formed in the top surface of a piston, and a fuel injection valve for injecting fuel into the cavity in nearly the shape of a fan having a relatively small thickness. When the fuel injected in nearly the shape of a fan from the fuel injection valve is considered by being divided into a plurality of fuel segments in a radial direction, a side wall of the cavity has a first fuel deflection passage 82a and a second fuel deflection passage 82b for so deflecting at least two of the plurality of fuel segments as to pass near the spark plug. The side wall of the cavity is at least partly provided with a return portion 83 that protrudes toward the inside of the cavity. The first fuel deflection passage is not provided with the return portion 83 or is provided with the return portion having a short protrusion, and the second fuel deflection passage is provided with the return portion 83 having a long protrusion.