Crank mechanisms for asymmetrical non-sinusoidal piston motion profiles in opposed piston internal combustion engines

Abstract

A dual crank mechanism is introduced for controlling and optimizing asymmetry in the motion profile of at least one piston of an opposed piston internal combustion (OPIC) engine piston pair. The dual crank mechanism produces a substantially asymmetrical non-sinusoidal, but periodic, reciprocating motion profile of the right-hand piston. A single crank mechanism is also introduced for controlling non-sinusoidal, but mostly symmetric, piston motion profile for one or both pistons of an opposed piston pair. The two novel crank mechanisms may be advantageously used exclusively or in combination in order to optimize the piston motion in a novel high efficiency OPIC engine having an externally mounted combustion chamber, an external compressing means for injecting compressed fuel mixtures directly into the external combustion chamber, and reducing cylinder porting to a single exhaust port per cylinder due to improved scavenging resulting from the asymmetric non-sinusoidal piston profiles produced by the novel crank mechanisms.