Abstract: A high efficiency combined cycle internal combustion and steam engine includes a cylinder with a combustion chamber outward of a piston, a cylinder cap slideably mounted within the piston and a steam expansion chamber inside the piston. The cap can be heated to reduce condensation of steam. Steam remaining when a steam exhaust valve closes can be recompressed prior to admitting the next charge of steam. One valve or a pair of steam inlet valves connected in series act in cooperation to help maximize efficiency. The amount of steam admitted each stroke is regulated by shifting the phase of one steam admission valve of a pair to vary their overlap for determining the steam mass admitted each cycle. Other valves balance steam displacement with the steam generator output to use steam more efficiently.

Abstract: A combination internal combustion and steam engine includes a cylinder having a piston mounted for reciprocation therein with an internal combustion chamber and a steam chamber in the cylinder adjacent the piston and at least one steam exhaust port positioned to communicate with the steam chamber through the wall of the cylinder for exhausting steam at a location in the cylinder wall adjacent to an engine cylinder cap surface that is heated externally to assist in reducing chilling or condensation of steam entering the steam chamber from a boiler fired by waste combustion heat. The invention also permits steam admitted from a steam chest jacketing the cylinder cap to be exhausted from the engine when the steam chamber is in an expanded state whereupon residual steam is then recompressed prior to admitting the next charge of steam with the stream in the steam chamber being heated directly by the combustion chamber as well as by heat from the steam chest. An I.C. exhaust powered heater is a part of an I.C.

Abstract: A high efficiency combined cycle internal combustion and steam engine includes a cylinder having a piston mounted for reciprocation therein with an internal combustion chamber outward of the piston, a fixed cylinder cap sealingly and slideably mounted within the piston and a steam expansion/recompression chamber inside the piston adjacent the cylinder cap. The cylinder cap can be unheated or heated externally to reduce condensation of steam entering the steam chamber from a steam generator fired by waste combustion heat. Steam remaining in the cylinder when a steam exhaust valve closes at the top center position is recompressed during an inward stroke of the piston up to admission pressure prior to admitting the next charge of steam.