Abstract: A heat recovery system utilizing the principle of the Stirling engine includes a gas-containing chamber communicating through control valves alternately with hot and cool gas heat exchangers supplied with waste or other source heat fluid and coolant fluid, respectively, and a blower functions to circulate gas in the chamber alternately through the hot and cool gas heat exchangers and thus alternately to increase and decrease the gas pressure in the chamber. This alternate changing of gas pressure is utilized to operate a work-performing device. In one embodiment, a single chamber contains a piston reciprocative therein by said pressure change. In another embodiment, each of a pair of chambers is coupled through a blower selectively with a hot gas heat exchanger and a cool gas heat exchanger.

Abstract: An internal combustion engine includes a plurality of cylinders each containing a reciprocative piston connected to an output rotary power shaft. The cylinders communicate with a common fuel chamber sequentially through a rotary distribution valve driven by the output power shaft.Starting of the engine is achieved by delivering gaseous fluid to the fuel chamber and thence through the distribution valve to a cylinder under pressure sufficient to drive the piston inward in a power stroke. Combustible fuel is delivered to the fuel chamber at a pressure greater than cylinder combustion pressure, and combustion air is delivered to each cylinder from a source of external air under pressure through an inlet port which is opened and closed by the associated piston adjacent the bottom of the stroke thereof.