Internal combustion engine, particularly, a free-piston engine

Abstract From the Canadian patent

Internal combustion engine, more specifically a free-piston engine, having at least one cylinder and a piston arranged therein and guided to be movable and sealed. The piston performs axial stroke movements within cylinder chamber, and features cylindrical projections extending axially spaced from the piston to either side and having at least over part of their length a diameter inferior to the diameter of the piston. The projections are guided at least over some part of their length within axial cylinder bores and therein partially sealed. Combustion chambers are provided within the cylinder, which combustion chambers are formed and delimited by certain parts of the inside cylinder wall …