Abstract: A working gas pressure equalization system for a multiple-cylinder, double-acting hot gas engine such as a Stirling engine of the type having a plurality of pistons reciprocatable within the cylinders defining a plurality of generally isolated cycle volumes of a working gas separated by the pistons. The equalization system incorporates passages through the piston connecting rods which connect between a space between piston rings and an equalization volume defined between a pair of sliding rod seals. This volume is defined by portions from each of the cylinders and is connected with individual cycle volumes by a valve, such as a one-way check valve. When a pressure is experienced in one of the cycle volumes different from the minimum pressure maintained and the equalization volume, minute gas leakage across the piston rings enables pressure among the volumes to be equalized.

Abstract: A hydrogen production system for use in connection with Stirling engines. The production system generates hydrogen working gas and periodically supplies it to the Stirling engine as its working fluid in instances where loss of such working fluid occurs through usage through operation of the associated Stirling engine. The hydrogen gas may be generated by various techniques including electrolysis and stored by various means including the use of a metal hydride absorbing material. By controlling the temperature of the absorbing material, the stored hydrogen gas may be provided to the Stirling engine as needed.

Abstract: A hydraulic actuator for a multicylinder Stirling engine provided to enable modulation of the displacement of the engine. The hydraulic actuator incorporates a rotary vane configuration which provides relative rotational adjustment between components of a swashplate assembly. The relative rotation provides adjustments to the angle formed by the swashplate relative to its angle of rotation, and thus varies the stroke of each piston connecting rod, which thereby modulates the swept volume of the respective piston within its cylinder bore.

Abstract: An exhaust gas alternator system for a diesel powered motor vehicle including a Stirling engine operating through a heat input of waste heat from a diesel engine exhaust to drive an electrical alternator. The cooler of the Stirling engine receives liquid engine coolant. An auxiliary diesel fuel burner may be operated to provide heat input for said Stirling engine when the diesel engine is not operated. The system may be used in an exhaust circuit having a catalytic converter.

Abstract: A heater head assembly for a multi-cylinder heat engine the stirling engine, such as a multi-cylinder Stirling engine, having a plurality of regenerators and cylinders. Each regenerator has a regenerator manifold and each cylinder has a cylinder manifold. First identical cast heater tubes connect the regenerator manifold to first heater tube openings in a heater head manifold. Second identical cast heater tubes connect second heater tube openings in the heater head manifold to the cylinder manifold. The first and second heater tubes are parallel with respect to each other and form a pair of partial concentric staggered arrays. The heater tubes are rotationally asymmetric, having fin sections with less surface area upstream than downstream and thicknesses which decrease radially away from the central passageways of said heater tubes.