Patent ID: 9016256
Filing Date: 2015-04-28
Classification: F02B

Abstract:
1. A concentric cylinder engine comprising: a crankcase; a crankshaft rotationally disposed within the crankcase, the crankshaft having two outer piston crank throws and an inner piston crank throw disposed therebetween, the outer piston crank throws offset generally opposite the inner piston crank throw; an outer cylinder extending from the crankcase; a generally toroidal outer piston disposed within the outer cylinder, the outer piston reciprocally communicating with the outer piston crank throws of the crankshaft; a sleeve assembly having a sleeve valve reciprocally disposed within the outer piston; an inner piston disposed within the sleeve assembly, the inner piston reciprocally communicating with the inner piston crank throw of the crankshaft; said sleeve valve assembly comprising: