US Patent 7472696 Exhaust gas recirculation system with in-cylinder valve actuation

A method for recirculating exhaust gas includes operating an intake valve to open an intake port of a combustion chamber, operating an exhaust valve to open an exhaust port of the combustion chamber, and directing exhaust gas from the exhaust port to an exhaust recirculation port of the combustion chamber. The method also includes operating an exhaust recirculation valve to open the exhaust recirculation port to allow the exhaust gas to enter the combustion chamber and determining at least one valve actuation condition for controlling actuation of each of the intake valve and the exhaust recirculation valve.