Exhaust gas re-circulation with a compression release brake actuator

An internal combustion engine, comprising:

• a cylinder having a bore;
• a piston slidably disposed in said cylinder bore and movable relative to said cylinder between a top dead center position and a bottom dead center position;
• a cylinder head connected to said cylinder;
• an exhaust manifold connected to said cylinder head;
• a combustion chamber defined by said cylinder head, said piston and said cylinder;
• an exhaust valve connected to said cylinder head and being movable between a closed position and an open position, said exhaust valve having substantially zero lift relative to the cylinder head at the closed position and having a predetermined maximum amount of lift relative to said cylinder head at the open position, said exhaust valve being adapted to pass exhaust gas between said combustion chamber and said exhaust manifold at the open position and being adapted to block the passing of exhaust gas between said exhaust manifold and said combustion chamber at the closed position;
• an intake valve being connected to the cylinder head and being movable between a closed position and an open position, said intake valve having substantially zero lift relative to the cylinder head at the closed position and having a predetermined maximum amount of lift relative to said cylinder head at the open position, said intake valve being adapted to pass intake fluid flow between said intake manifold and said combustion chamber at the open position of the intake valve and being adapted to block the passing of intake fluid flow between the combustion chamber and the intake manifold at the closed position of the intake valve;
• a camshaft being operatively connected to move the intake and exhaust valves between the closed and open positions, said camshaft determining the maximum amount of lift of each of the exhaust and intake valves at the open position, said exhaust valve being movable to the open position during movement of the piston within a first predetermined range of piston movement and said intake valve being movable to the open position during movement of the piston within a second predetermined range of piston movement;
• and
• a compression release brake actuator being operatively connected to said exhaust valve and being actuatable during said first predetermined range of piston movement to modify said movement of the exhaust valve between said open and closed positions and maintain the exhaust valve at said intermediate position during at least a portion of said first range of piston movement and a second range of piston movement and provide a re-circulation of the exhaust gas between said exhaust manifold and said combustion chamber.

A method of controlling internal exhaust gas re-circulation in an internal combustion engine having a compression release brake actuator, an exhaust valve, an intake valve, an exhaust manifold, a camshaft operatively connected to move said exhaust valve between an open position at which said exhaust valve is at a maximum lift position and a closed position, a combustion chamber defined by a piston, a cylinder and a cylinder head, said piston being movable between a top dead center position and a bottom dead center position;

• comprising the steps of:
• moving the exhaust valve mechanically with the camshaft from the closed position to the open position in response to the piston being at a first predetermined range of piston movement;
• moving the intake valve mechanically by the camshaft from the closed position to the open position in response to the piston being at a second predetermined range of piston movement different than said first predetermined range of piston movement;
• actuating the compression release brake actuator in response to the piston being at a predetermined position within at least one of said predetermined first and second predetermined ranges of piston movement;
• maintaining the exhaust valve at the intermediate lift position subsequent to actuation of the compression release brake actuator and during a predetermined range of piston movement;
• and
• passing exhaust gas between the exhaust manifold and the combustion chamber while the exhaust valve is at the intermediate position.