Revolving cylinder engine

The primary claimed benefit of the revolving cylinder, axial piston engine is that a four-cycle, reciprocating piston engine can be achieved without the need for a complex and expensive valve train. The intake and exhaust flows are controlled by simple ports in the cylinder heads. Costs are further reduced because all cylinders at each end of the engine share a common fuel injector and/or spark plug. Additionally, the designs are typically compact and lightweight.