Patent ID: 7717084

Claim:
A controller of an internal combustion engine which is operable in a compression ignition operation mode in which an air-fuel mixture charged into a combustion chamber of a cylinder is compressed, and thereby, the fuel of the air-fuel mixture is self-ignited and combusted, and in a spark ignition operation mode in which the fuel of the air-fuel mixture is ignited and combusted by spark ignition, the controller comprising a first intermediate mode which, in a case where the operation mode of the internal combustion engine is shifted from the compression ignition operation mode to the spark ignition operation mode, is interposed between both the operation modes, and a second intermediate mode which, in a case where the operation mode of the internal combustion engine is shifted from the spark ignition operation mode to the compression ignition operation mode, is interposed between both the operation modes, and the controller comprising an intermediate mode control means which controls an air supply amount and a fuel supply amount to the combustion chamber so that the air-fuel ratio of the air-fuel mixture becomes rich gradually in the first intermediate mode, and which controls the air supply amount and the fuel supply amount to the combustion chamber so that the air-fuel ratio of the air-fuel mixture becomes lean gradually in the second intermediate mode.