Internal combustion engine control device

Abstract

To increase an opportunity for performing lean operation control.SOLUTION: A control device 60 is applied to a spark ignition internal combustion engine 10 having a cylinder injection valve 42, in which a filter 33 is provided in an exhaust passage 31. When a stoichiometric air-fuel ratio is set as a target air-fuel ration, a processing circuit 61 of the control device 60 performs stoichiometric operation control for operating the internal combustion engine 10 in a state that the number of cylinder injections in one combustion cycle of the internal combustion engine 10 is set to be one or more times. The processing circuit 61 determines whether or not an accumulation amount of particulate matters on the filter 33 is equal to or more than a determination accumulation amount. When the accumulation amount is determined to be equal to or more than the determination accumulation amount, the processing circuit 61 performs lean operation control for setting an air-fuel ratio closer to a lean side than the stoichiometric air-fuel ratio as a target air-fuel ratio and for operation the internal combustion engine 10 in a state that the number of cylinder injections in one combustion cycle of the internal combustion engine 10 is set to be one time.SELECTED DRAWING: Figure 1

Claims

1. This is applied to a spark-ignition type internal combustion engine that is equipped with an in-cylinder injection valve for injecting fuel into the cylinder, and a filter for collecting particulate matter contained in the exhaust gas is installed in the exhaust passage. The system includes a processing circuit that controls the fuel injection of the in-cylinder injection valve, The aforementioned processing circuit is When the stoichiometric air-fuel ratio is set as the target air-fuel ratio, stoichiometric operation control is performed to operate the internal combustion engine with the number of injections from the in-cylinder injector set to one or more times in one combustion cycle of the internal combustion engine. The amount of particulate matter deposited on the filter is determined to be equal to or greater than the determined amount of deposited material. If it is determined that the amount of deposit is equal to or greater than the determined amount of deposit, the target air-fuel ratio is set to a leaner air-fuel ratio than the stoichiometric air-fuel ratio, and lean operation control is performed to operate the internal combustion engine with the number of injections from the in-cylinder injector fixed to one per combustion cycle of the internal combustion engine. If the pressure of the fuel supplied to the in-cylinder injection valve is less than the determination fuel pressure, the execution of the lean operation control is prohibited, and the pressure of the fuel supplied to the in-cylinder injection valve is increased to or above the determination fuel pressure. Internal combustion engine control device.

2. The processing circuit also prohibits the execution of the lean operation control if it is predicted that the amount of fuel injected by the in-cylinder injector when the lean operation control is executed will be less than the minimum injection amount of the in-cylinder injector. The internal combustion engine control device according to claim 1.

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