Control system for an internal combustion engine

A control system for an internal combustion engine comprising:

• an ineffective fuel-supply means for supplying ineffective fuel to the combustion chamber of an internal combustion engine;
• an EGR means for recirculating the exhaust gas from the engine into the combustion chamber of the engine;
• an EGR limiting means for limiting the exhaust gas recirculated by said EGR means when the ineffective fuel is being supplied to the engine by said ineffective fuel supply means;
• and wherein
• said internal combustion engine is equipped with a variable valve timing device for varying the open-close timings of the intake valves and the exhaust valves of the cylinders, and said EGR limiting means controls said variable valve timing means to change the open-close timings of the intake valves or the exhaust valves to limit the recirculation of the exhaust gas to effect both exhaust gas recirculation and secondary fuel injection simultaneously.

A control system for an internal combustion engine comprising:

• an ineffective fuel-supply means for supplying ineffective fuel to the combustion chamber of an internal combustion engine;
• an EGR means for recirculating the exhaust gas from the engine into the combustion chamber of the engine;
• and
• an ineffective fuel limiting means for limiting the supply of ineffective fuel by said ineffective fuel-supply means when the exhaust gas is recirculated by said EGR means.

An internal combustion engine comprising:

• a main fuel-supply means for supplying, into said engine, the fuel that burns in the combustion chamber based on the operating conditions of the internal combustion engine;
• an ineffective fuel-supply means for supplying, into said engine, the ineffective fuel to the combustion chamber of the engine;
• an EGR means for recirculating the exhaust gas from the engine into the combustion chamber of the engine;
• and
• a correction means for estimating the amount of the ineffective fuel in the exhaust gas recirculated by said EGR means to correct the amount of fuel supplied to the engine by said main fuel-supply means based on the estimated amount.

A control system for an internal combustion engine comprising:

• an ineffective fuel-supply means for supplying ineffective fuel to the combustion chamber of an internal combustion engine;
• an EGR means for recirculating the exhaust gas from the engine into the combustion chamber of the engine;
• an EGR limiting means for limiting the exhaust gas recirculated by said EGR means when the ineffective fuel is being supplied to the engine by said ineffective fuel supply means;
• and
• a controller to effect both exhaust gas recirculation and secondary fuel injection simultaneously and to discharge the ineffective fuel supplied by the ineffective fuel supply means out of the cylinder during an exhaust stroke of the engine.

A control system for an internal combustion engine comprising:

• an ineffective fuel-supply means for supplying ineffective fuel to the combustion chamber of an internal combustion engine;
• an EGR means for recirculating the exhaust gas from the engine into the combustion chamber of the engine;
• an EGR limiting means for limiting the exhaust gas recirculated by said EGR means when the ineffective fuel is being supplied to the engine by said ineffective fuel supply means;
• and
• a controller to decrease an amount of main fuel injected to accommodate any ineffective fuel which remains in the cylinder so that an amount of fuel that contributes to combustion in a next combustion cycle is in agreement with a target amount of main fuel injected.