Patent attributes
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.
