Abstract: A two-cycle, two-cylinder opposed piston internal combustion engine having means for continuously adjusting the stroke of the engine and the blocking and unblocking of intake, transfer and exhaust ports with respect to each other as the engine is operating. Corresponding pistons of each cylinder are connected to respective ends of pivotally mounted rocker arms so that pistons in one cylinder move oppositely with respect to pistons in the other cylinder, the piston side surfaces alternately blocking and unblocking transfer and exhaust ports. In a particular embodiment, the rocker arms are each fitted with a flat spring positioned so as to be in contact with the end of the associated piston rod and deflecting to allow the pistons to move apart at an increased speed in advance of the crankshaft. The springs are secured and limited so as to provide increasing spring moment as the springs are deflected.

Abstract: A two-cycle, two-cylinder opposed piston internal combustion engine having means for continuously adjusting the stroke of the engine and the blocking and unblocking of intake, transfer and exhaust ports with respect to each other as the engine is operating. Corresponding pistons of each cylinder are connected to respective ends of pivotally mounted rocker arms so that pistons in one cylinder move oppositely with respect to pistons in the other cylinder, the piston side surfaces alternately blocking and unblocking transfer and exhaust ports. Two connecting rods are provided, one of which is attached at one end to each of the rocker arms at a pivot point distal from the rocker arm pivotal mount and at the other end to a rotatably mounted eccentric, one end of which is formed into a shaft containing a power drive gear operatively connected to a drive shaft, the eccentric being rotated due to an up and down motion of the connecting rod.