Internal combustion engine having a piston with truncated cone wall cavity

The engine has a cavity comprising a tapered wall (36) that extends in an equidistant manner on both sides of an impact point (26) of a fuel spray (24) to cause an uniform splitting of the spray. The uniform splitting of the spray assures uniform mixing of the fuel with the oxygen contained in the cavity. The wall is arranged perpendicular to a spraying axis for dissipating a part of energy of the spray to the point.