Combustion engine including cam phase-shifting

An internal combustion engine, comprising:

• an engine block defining at least one cylinder;
• a head connected with said engine block, the head including an air intake port, and an exhaust port;
• a piston slidable in the cylinder;
• a combustion chamber being defined by said head, said piston, and said cylinder;
• an air intake valve movable to open and close the air intake port;
• an air supply system including at least one turbocharger fluidly connected to the air intake port;
• a fuel supply system operable to inject fuel into the combustion chamber;
• a first cam and second cam rotatable to operate the air intake valve;
• a phase shifting device configured to shift rotational phase of one of the first and second cams;
• and
• an adjustment device adapted to adjust the position of the second cam relative to a rocker arm operably coupled with the air intake valve.

A method of operating an internal combustion engine including at least one cylinder and a piston slidable in the cylinder, the method comprising:

• imparting rotational movement to a first turbine and a first compressor of a first turbocharger with exhaust air flowing from an exhaust port of the cylinder;
• imparting rotational movement to a second turbine and a second compressor of a second turbocharger with exhaust air flowing from an exhaust duct of the first turbocharger;
• compressing air drawn from atmosphere with the second compressor;
• compressing air received from the second compressor with the first compressor;
• supplying pressurized air from the first compressor to an air intake port of a combustion chamber in the cylinder via an intake manifold;
• operating a fuel supply system to inject fuel directly into the combustion chamber;
• and
• operating an air intake valve to open the air intake port to allow pressurized air to flow between the combustion chamber and the intake manifold,
• wherein the engine has a variable compression ratio;
• wherein operating the air intake valve includes operating the air intake valve via at least first and second rotatable cams associated with the air intake valve;
• and
• shifting rotational phase of at least one of the first cam and a camshaft including the first cam;
• wherein the engine includes an adjustment device adapted to adjust the position of the second cam relative to a rocker arm operably coupled with the air intake valve.

A method of controlling an internal combustion engine having a variable compression ratio, said engine including a block defining a cylinder, a piston slidable in said cylinder, and a head connected with said block, said piston, said cylinder, and said head defining a combustion chamber, the method comprising:

• pressurizing air;
• supplying said air to an intake manifold of the engine;
• maintaining fluid communication between said combustion chamber and the intake manifold during a portion of an intake stroke and through a portion of a compression stroke;
• wherein the maintaining includes operating an air intake valve via at least first and second rotatable cams associated with the air intake valve;
• shifting rotational phase of at least one of the first cam and a camshaft including the first cam;
• and
• injecting fuel directly into the combustion chamber;
• wherein the engine includes an adjustment device adapted to adjust the position of the second cam relative to a rocker arm operably coupled with the air intake valve.

A method of operating an internal combustion engine including at least one cylinder and a piston slidable in the cylinder, the method comprising:

• supplying pressurized air from an intake manifold to an air intake port of a combustion chamber in the cylinder;
• operating an air intake valve to open the air intake port to allow pressurized air to flow between the combustion chamber and the intake manifold substantially during a portion of a compression stroke of the piston,
• wherein the engine has a variable compression ratio;
• wherein operating the air intake valve includes operating the air intake valve via at least first and second rotatable cams associated with the air intake valve;
• shifting rotational phase of at least one of the first cam and a camshaft including the first cam;
• and
• injecting fuel into the combustion chamber after the intake valve is closed, wherein the injecting includes supplying a pilot injection of fuel at a crank angle before a main injection of fuel;
• wherein the engine includes an adjustment device adapted to adjust the position of the second cam relative to a rocker arm operably coupled with the air intake valve.