US Patent 9334794 Rotary internal combustion engine with pilot subchamber and ignition element

A rotary engine including an insert in one of the walls of the outer body having a pilot subchamber defined therein communicating with the internal cavity of the engine. An ignition element extends in an element cavity defined through the insert adjacent the subchamber. A portion of the element is in communication with the subchamber through a communication opening defined in the insert between the element cavity and the subchamber. The communication opening has a cross-section smaller than a corresponding cross-section of the portion of the element. An outer body for a rotary engine and a method of combusting fuel in a rotary engine are also provided.