Patent ID: 6932031
Filing Date: 2005-08-23
Classification: F02B

Abstract:
1. A scavenging system for a gas-powered intermittent engine comprising: a power piston within a piston cylinder that divides the piston cylinder into a combustion chamber located above the power piston and an air chamber located below the power piston; a plenum chamber connecting the air chamber to the combustion chamber; a first check valve located between the air chamber and the plenum chamber supporting a flow of air from the air chamber into the plenum chamber; a second check valve located between the plenum chamber and the combustion chamber supporting a flow of the air from the plenum chamber into the combustion chamber; the power piston being moveable in response to an ignition of combustion gas in the combustion chamber between a top position at which a volume of the combustion chamber is minimized and a volume of the air chamber is maximized and a bottom position at which the volume of the combustion chamber is maximized and the volume of the air chamber is minimized; the first check valve supports the flow of air from the air chamber into the combustion chamber during the downward movement of the power piston toward the bottom position; and the second check valve supports the flow of air from the plenum chamber into the combustion chamber when the power piston is in the vicinity of the bottom position to initiate a scavenging operation in the combustion chamber as pressure in the plenum chamber exceeds pressure in the combustion chamber.