Method of reducing pumping losses and improving brake specific fuel consumption for an internal combustion engine

摘要

A method is provided for improving the performance of an internal combustion engine, comprising the steps of inducting a charge of fluid into the combustion chamber of the engine, holding the intake valve of the combustion chamber open during a portion of the compression stroke of the piston in the combustion chamber, expelling a portion of the inducted charge from the combustion chamber by movement of the piston in its compression stroke while the intake valve is held open, preventing the expelled portion of the inducted charge from communicating with the atmosphere by providing a check valve between the induction manifold and the atmosphere, the check valve only permitting flow in the direction from the atmosphere into the induction manifold; and closing the intake valve during the remainder of the compression stroke and after the portion of the induction charge is expelled.