PISTON ARRANGEMENT AND INTERNAL COMBUSTION ENGINE

An homogeneous charge compression ignition internal combustion engine has a combustion cylinder, and a combustion piston head movable along a piston axis within the combustion cylinder. A compression ignition cylinder is fluidically connected to the combustion cylinder. A compression ignition piston moves in reciprocating motion within the compression ignition cylinder. The compression ignition piston is adapted to be moved between a bottom dead centre position corresponding to a maximum volume of the compression ignition cylinder to a top dead centre position corresponding to a minimum volume of the compression ignition cylinder during operation of the engine to create a pressure spike within the combustion cylinder thereby causing auto ignition of a fuel/air mixture within the combustion cylinder.