Patent ID: 7992538

Claim:
A method of controlling an internal combustion engine, the method comprising: closing an exhaust valve of a combustion chamber of said engine during a cylinder cycle prior to opening an intake valve of said combustion chamber; when a desired engine torque is a predetermined torque or greater, supplying a first pilot fuel into said combustion chamber after said exhaust valve closing during the cylinder cycle so that said first pilot fuel combusts before said intake valve opening during the cylinder cycle, and supplying a first main fuel into said combustion chamber after the combustion of said first pilot fuel during the cylinder cycle so that said first main fuel is self ignited after said intake valve closes during the cylinder cycle and combusts after a top dead center after said intake valve closing; and when a desired engine torque is less than said predetermined torque, supplying a second main fuel into said combustion chamber so that said second main fuel is self ignited after said intake valve closes during the cylinder cycle and combusts after a top dead center after said intake valve closing while no combustion occurs between said exhaust valve closing and said intake valve opening during the cylinder cycle.