Nutating disc engine

A nutating disc engine (also sometimes called a disc engine) is an internal combustion engine comprising fundamentally of one moving part and a direct drive onto the crankshaft. Initially patented in 1993, it differs from earlier internal combustion engines in a number of ways and utilizes a circular rocking or wobbling nutating motion, drawing heavily from similar steam-powered engines developed in the 19th century, and similar to the motion of the non-rotating portion of a swash plate on a swash plate engine.

In its basic configuration the core of the engine is a nutating non-rotating disc, with the center of its hub mounted in the middle of a Z-shaped shaft. The two ends of the shaft rotate, while the disc "", (performs a wobbling motion without rotating around its axis). The motion of the disc circumference prescribes a portion of a sphere. A portion of the area of the disc is used for intake and compression, a portion is used to seal against a center casing, and the remaining portion is used for expansion and exhaust. The compressed air is admitted to an external accumulator, and then into an external combustion chamber before it is admitted to the power side of the disc. The external combustion chamber enables the engine to use diesel fuel in small engine sizes, giving it unique capabilities for unmanned aerial vehicle propulsion and other applications. One significant benefit of the nutating engine is the overlap of the power strokes.

Power is transmitted directly to the output shaft, (the crankshaft), completely eliminating the need for complicated linkages essential in a conventional piston engine (to convert the piston's linear motion to rotating output motion). Since the disc does not rotate, the seal velocities are lower than in an equivalent IC piston engine. The total seal length is rather long, however, which may negate this advantage.

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