US Patent 8356585 Planetary rotary engine

A planetary engine includes a charge compression system for compressing a charge of air and/or an air and fuel mixture that is precompressed by rotation of the rotors and supplied into a combustion chamber through a rotary valve that may be actively adjusted during operation of the engine to vary the intake valve opening size and/or timing. Exhaust valves may likewise be actively adjustable rotary valves for further engine control. A compression insert mounted between the end wall assemblies absorbs combustion forces and provides rigidity to the engine, as well as occupies all or nearly all of the volume between the rotors at the minimum volume of the combustion chamber to improve the compression ratio of the engine.