Elliptical rotary engine

1. Field of the Invention An elliptical potary engine having a cylindrical rotor that rotates within a cyclindrical housing having cycling chambers defined between a plurality of radially extending piston vanes disposed within vane channels within the rotor. During the rotation of the rotor, the piston vanes are urged radially outward by cam-like elliptical piston vane guides associated with the head and the base of the housing and are returned therein by the elliptical interior wall as the diameter thereof decreases.