Mazda Files Patent for Rotary Engine Exhaust Gas Recirculation System

On August 20, 2024, Mazda filed a patent application with the United States Patent and Trademark Office (USPTO) for an Exhaust Gas Recirculation (EGR) system designed specifically for rotary engines. The system divides the exhaust passages in the rotor housing into two types of outlets: lateral exhaust ports direct exhaust gases to the turbocharger, while peripheral exhaust ports channel exhaust gases into an EGR cooler to reduce intake air temperature. Under high-load conditions, the cooled gases can be routed directly to a secondary catalytic converter. Mazda previously unveiled the Iconic SP concept car at the 2023 Japan Mobility Show and plans to debut the Vision X-Coupe concept—also equipped with a rotary engine—at the 2025 Japan Mobility Show.