Piston system for a compression engine

A piston system for a compression engine comprising:

• a main piston having a top surface and an aperture passing from the top surface through a bottom surface;
• an inner piston having an inner piston top surface and a cylindrical outer surface, wherein the inner piston and the main piston are configured such that the cylindrical outer surface of the inner piston is received in and travels through the aperture;
• a plurality of connecting rods connecting the main piston to a crankshaft of the engine;
• an inner piston connecting rod connecting the inner piston to the crankshaft,
• wherein a connection between the inner piston connecting rod and the crankshaft provides an offset such that during a rotation of the crankshaft, the inner piston top surface transitions from being below the main piston top surface prior to the main piston reaching a top dead center position of the stroke cycle to being flush with the main piston top surface when or after the main piston reaches the top dead center position of the stroke cycle, and
• wherein the main piston is connected to the plurality of main piston connecting rods with a single main piston pin and wherein the inner piston connecting rod includes an aperture sized and positioned to accommodate the main piston pin during relative movement of the inner piston and main piston during a stroke cycle.