Mazda not only has homogeneous charge compression ignition technology on the horizon for a debut next year, the Japanese manufacturer also has filed a patent application for a triple-charged engine, which was recently published by the United States Patent and Trademark Office (USPTO).

The diagram and drawing filed with the USPTO reveal a petrol engine with what appears to be a pair of conventional, exhaust-driven turbochargers, which operate in parallel with an electrically-operated supercharger. The electric supercharger would be provide low-end power while the pair of turbos spool up.

Mazda’s electric supercharger is likely to be run off its own i-ELOOP capacitive storage system, which, in the Mazda 6, recovers energy from braking and converts it to electricity, which it stores in capacitors for use towards equipment such as the air-conditioning, sound system and lighting.

Interestingly, one of the images in the patent filing reveal the engine configured longitudinally, which means a rear-wheel-drive setup. Currently, the Miata/MX-5 is the only such configured car in Mazda’s line-up. The Hiroshima-based automaker’s Skyactiv-X engine will be equipped with an electric supercharger, though it was not clear if that powerplant adopts the triple-charger setup in this patent filing.

Mazda says it will continue to perfect the internal combustion engine, which it says will remain the main source of power for vehicles globally for years to come, and hence has the greatest potential for emissions reduction. Its launch plan for future technologies sees Skyactiv-X come to market in 2019, with the second-generation Skyactiv-D (diesel) engines due a year later.