How It Works
The RCV 4-cycle engine has only one more moving component than a 2-cycle engine -the rotating cylinder  itself.  The cylinder is suspended between two bearings which allow it to rotate freely around the piston; the piston, and crank are entirely conventional. A gear formed around the base of the cylinder meshes with a gear on the crank.  As the piston reciprocates and the crank turns, the cylinder rotates around the piston.
SP Cross Section
At the top end of the rotating cylinder there is a single port leading to the combustion chamber.  This is surrounded by a fixed timing ring with three radially arranged ports; inlet, ignition and exhaust.  This simple valve arrangement serves the combustion chamber as the engine cycles through the conventional 4-cycles: induction, compression, power and exhaust.  Ignition is achieved through a standard 4-cycle glow plug exposed once only during each complete cycle.

The rotating cylinder is effectively combined with the rotary valve in a single component hence - RCV - Rotating Cylinder Valve

CD Cross Section


Breakdown of Main Components
SP Series



CD Series