Engine control device

Abstract

The invention provide an engine control device. During vehicle driving, deterioration of driving can be prevented and the catalyst can be pre-heated. The PCM (60) performs a catalyst early warming control (AWS control) for accelerating warm-up of a catalytic device. When the catalytic device (35) is not in an activated state and a vehicle is traveling, the PCM (60) is configured to perform: a fuel injection control to inject fuel such that a homogeneous fuel-air mixture can be formed in a combustion chamber (11) of an engine (10) so as to generate a homogeneous combustion; an intake air amount control to increase intake air amount; and an ignition control to retard ignition timing from a reference ignition timing. In addition, the PCM (60) is configured to vary ignition timing retard amount corresponding to a difference between the ignition timing retarded by the ignition timing control and the reference ignition timing, in accordance with engine speed and/or engine load.

Description

technical field [0001] The present invention relates to an engine control device, and more particularly, to an engine control device for performing early warm-up control on a catalyst device provided in an exhaust passage. Background technique [0002] Conventionally, a technology called AWS (Accelerated Warm-up System: Accelerated Warm-up System) has been implemented in order to realize early activation of a catalyst device provided in an exhaust passage in a spark ignition engine. This AWS is a technology that increases the amount of intake air when the catalyst device is in an inactive state, for example, immediately after a cold start of the engine, compared to when it is in an active state under the same operating state (for example, idling operation). amount, and delay the ignition timing beyond the compression top dead center, so that the mixture gas is post-combusted in the expansion stroke, thereby increasing the temperature of the exhaust gas and increasing the hea...

AI Technical Summary

Problems solved by technology

[0004] Therefore, it is conceivable to perform AWS control while the vehicle is running, but when the weakly stratified combustion is performed while the vehicle is running like the technology described in Patent Document 1, the desired weakly stratified combustion may not be formed when the operating state of the engine changes. layer state, which produces misfires etc.

On the other hand, it is conceivable to perform homogeneous combustion (combust by forming a homogeneous air-fuel mixture in the combustion chamber) instead of weakly stratified combustion in AWS control. Therefore, when the ignition timing is delayed in homogeneous combustion as in the case of applying weak stratified combustion, misfires and the like may occur and drivability may deteriorate

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