Abstract: A rotary engine of the internal combustion type comprising a housing having therein a main rotor chamber providing a main rotor axis and having therein combustion and exhaust blocking rotor chambers which intersect the main rotor chamber and which provide combustion rotor and exhaust blocking rotor axes spaced from and parallel to the main rotor axis. A lobed main rotor is rotatable in the main rotor chamber, and combustion and exhaust blocking rotors are rotatable in the combustion and exhaust blocking rotor chambers. The combustion rotor is provided with circumferentially spaced combustion cavities therein to receive the lobes, and the exhaust blocking rotor is provided with circumferentially spaced cavities to receive the lobes. The main, combustion and exhaust blocking rotors are geared together and the peripheries of the combustion and exhaust blocking rotors are substantially tangent to the periphery of the main rotor between the lobes thereon.