Energy harvesting heat engine and actuator

A rotary heat engine comprising:

• a central crankshaft having a first end and a second end and defining an axis of rotation, the central crankshaft further including at least one piston attachment member having an offset axis which is offset from the axis of rotation, with at least one axially displaced coupling point about the offset axis;
• a plurality of cylinder assemblies, at least one cylinder assembly including:
• a cylinder member having an elongated structure defining a bore and including a top end and a bottom end, the cylinder member rotatably positioned about the central crankshaft so as to rotate about the axis of rotation, the cylinder member further including an opening proximate the top end;
• a piston member slidably positionable within the bore;
• a connecting rod having a piston coupling end coupled to the piston member and a distal end coupled to the at least one axially displaced coupling point of the at least one piston attachment member;
• and
• a rolling diaphragm positioned between the piston and the top end so as to define a working volume therebetween, the rolling diaphragm having a top end, a bottom panel and an elongated portion, the top end being sealingly attached to the cylinder member proximate the top end and in fluid communication with the opening therein, with the bottom panel overlying the piston so that movement of the piston rolls the elongated portion of the rolling diaphragm over itself between the piston and the bore of the cylinder member;
• and
• a heat exchanger assembly associated with the at least one cylinder assembly including:
• a heat exchanger body having an outer surface and an inner chamber, the heat exchanger body having a refrigerant positioned within the inner chamber;
• a connecting pipe having an inner bore, a heat exchanger end and a cylinder member end, the heat exchanger end coupled to the heat exchanger body, and the cylinder member end coupled to the opening in the cylinder member, thereby placing the inner chamber in fluid communication with the opening of the cylinder member, and the working volume of the rolling diaphragm through the opening.