ALEXANDRIA, Va., Oct. 8 -- United States Patent no. 12,435,681, issued on Oct. 7, was assigned to REGENSYS LTD (Crieff, Great Britain).

"Stirling engine with at least four piston assemblies" was invented by Howard Sargent (Crieff, Great Britain).

According to the abstract* released by the U.S. Patent & Trademark Office: "A Stirling engine comprising a first cylinder comprising a piston configured to separate at least two expansion or compression chambers of the first cylinder, and a second cylinder comprising a piston configured to separate at least two expansion or compression chambers of the second cylinder. The pistons of the first and second cylinders are connected, such that the first and second cylinders form a first piston assembly...