Stirling cycle rotary engine

A Stirling cycle rotary engine for producing mechanical energy from heat generated by a solar powered heat source, the engine comprising:

• an engine housing having an interior toroidal cavity with a central housing axis for receiving a working gas, the engine housing further having a cool gas inlet port, a compressed gas outlet port, a heated gas inlet port, and a heated gas outlet port;
• at least three rotors each fixedly mounted to a respective rotor shaft and independently rotatable within the toroidal cavity about the central axis;
• each of the rotors including a pair of rotor blocks spaced radially on diametrically opposing sides of the respective rotor shaft, each rotor block having a radially fixed outer surface for sealed rotational engagement with the engine housing;
• an output shaft rotatable about a output shaft axis parallel with the central housing axis;
• at least three pairs of elliptical gears for regulating rotational movement of the rotors within the toroidal cavity, each pair of elliptical gears including a rotor shaft gear fixedly mounted to a respective rotor shaft and an intermeshing output shaft gear fixedly mounted to the output shaft;
• a first heat exchanger in fluid communication with the interior cavity via the compressed gas outlet port for partially heating the working gas;
• a second heat exchanger thermally connected to the heat source and in fluid communication with the interior cavity via the heated gas inlet port for additional heating of the working gas;
• a third heat exchanger in fluid communication with the heated gas outlet port and thermally connected to the first heat exchanger for removing heat from the working gas and for supplying heat to the first heat exchanger;
• and
• a fourth heat exchanger in fluid communication with the cool gas inlet port and spaced in the flow path between the third heat exchanger and the toroidal cavity for removing excess heat from the working gas.

A method of producing mechanical energy from heat generated by a heat source utilizing an engine including an engine housing having an interior toroidal cavity with a central housing axis, a plurality of rotors each fixedly mounted to a respective rotor shaft and independently rotatable within the toroidal cavity about the central axis, each of the rotors including a pair of rotor blocks spaced radially on diametrically opposing sides of the respective rotor shaft, and rotor control means for regulating angular reciprocation of the rotors within the interior toroidal cavity to control a volume increase or decrease in working chambers spaced between rotor blocks. the method comprising:

• compressing a working gas in a first working chamber spaced between first and second rotor blocks;
• passing the compressed working gas through a first heat exchanger for partially heating the compressed working gas;
• passing the compressed working gas through a second heat exchanger thermally connected to the heat source for additional heating of the compressed working gas;
• returning the heated compressed gas to a second working chamber spaced between the second and a third rotor block and isolated from the first working chamber;
• rotating the third rotor block to expand the second working chamber volume and produce work in response to the expanded working gas;
• passing the expanded working gas through a third heat exchanger thermally connected to the first heat exchanger for removing heat from the expanded working gas and for supplying heat to the first heat exchanger;
• passing the expanded working gas through a fourth heat exchanger for removing excess heat from the expanded working gas before returning the working gas to the toroidal cavity;
• and
• returning the working gas from the fourth heat exchanger to the toroidal cavity.