Patent ID: 7891326

Claim:
An engine of an internal combustion type comprising: a two-stroke engine having a cylinder with a movable piston, that defines a combustion chamber; an intake port in direct communication between said combustion chamber and with environmental air at atmospheric pressure and an exhaust port wherein said intake port and said exhaust port are disposed so that during piston movement said intake port is open after said exhaust port has opened following combustion in said combustion chamber and said intake port is closed before said exhaust port is closed by piston movement; a retro-tube attached to said exhaust port wherein said retro-tube is of approximately constant diameter and having a volume approximately equal to a swept volume of said piston movement in said cylinder; a plenum chamber having a diameter approximately equal to three times the diameter of said retro-tube is in communication with an exhaust end of said retro-tube at a retro-tube port; said plenum chamber having an exhaust tube port opposed to said retro-tube port that is at least the same diameter as said retro-tube and an exhaust receiver tube attached at said exhaust tube port; and said plenum chamber having an air tube port approximately orthogonal to a center line of said retro-tube and said exhaust tube port.