JP2005248703A5 - - Google Patents

Claims (6)

A fuel injection valve for injecting fuel into the engine combustion chamber;
An EGR device that recirculates part of the engine exhaust as EGR gas to the engine combustion chamber;
A control device for an internal combustion engine comprising an in-cylinder pressure sensor for detecting a pressure in the engine combustion chamber,
A combustion timing calculating means for calculating a combustion pressure characteristic value corresponding to a combustion timing including at least one of an ignition delay period and a combustion period based on the pressure in the combustion chamber detected by the in-cylinder pressure sensor;
Control means for controlling the EGR device to adjust the EGR gas amount so that a combustion pressure characteristic value corresponding to the combustion timing calculated by the combustion timing calculation means becomes a predetermined target value;
The control apparatus of the internal combustion engine provided with.   The combustion timing calculation means is configured to calculate the PV after the start of fuel injection from the fuel injection valve based on the product PV of the combustion chamber pressure P detected by the cylinder pressure sensor and the combustion chamber volume V determined from the crank angle θ. Is calculated as a combustion pressure characteristic value corresponding to the combustion timing, and the control means sets the EGR gas amount so that the ΔT becomes a predetermined target value. The control device for an internal combustion engine according to claim 1, wherein the control is performed.   The combustion timing calculating means further calculates a product PVbase of a combustion chamber pressure determined only by piston compression and a combustion chamber volume determined from a crank angle when it is assumed that no combustion occurs in the combustion chamber, and the PV is a maximum value. A difference ΔPVmax between PVmax and PVbase is calculated using the value of PVbase at a crank angle θmax that becomes PVmax, and the control means further controls the values so that the values of ΔPVmax and θmax become predetermined target values, respectively. The control device for an internal combustion engine according to claim 2, wherein the fuel injection amount from the fuel injection valve and the fuel injection timing are controlled.   The control device for an internal combustion engine according to claim 2 or 3, wherein the target value is determined according to an engine speed and an accelerator opening.   The control device for an internal combustion engine according to claim 4, wherein the internal combustion engine is a compression ignition engine.   The control means further includes a normal combustion mode in which fuel is injected at a later stage of the compression stroke to perform combustion with a large excess air ratio, and a low temperature in which the fuel injection timing is advanced from the normal combustion mode and the EGR gas amount is increased 6. The control device for an internal combustion engine according to claim 5, wherein the control is performed while switching between the combustion modes, and the EGR gas amount control based on the value of ΔT is performed during the low temperature combustion mode operation of the engine.