Combustion control device for an engine

Abstract

A combustion control device for an engine, comprises a fuel injection valve (9) for injecting a fuel into a combustion chamber (10), ignition timing adjustment unit (19) for adjusting an ignition timing of a mixture inside the combustion chamber (10), and control unit (26) for controlling the fuel injection valve (9) and the ignition timing adjustment unit (19). The control unit (26) controls the fuel injection valve (9) so as to execute at least a first injection which is conducted within the interval from an intake stroke to a compression stroke and a second injection conducted in the vicinity of a compression top dead center after the execution of the first injection, and controls the ignition timing adjustment means (19) so that the mixture formed by a fuel injected by the first injection and second injection and an intake air or the like is ignited after completion of the injection of the second injection.

Description

technical field [0001] The present invention relates to a combustion control device of an engine, and particularly relates to a combustion control device of an engine capable of performing premixed combustion which greatly reduces NOx and smoke dust in a wider operating range. Background technique [0002] Conventionally, in a diesel engine, when the cylinder (combustion chamber) reaches high temperature and high pressure, that is, when the piston is near compression top dead center, fuel is injected for combustion. [0003] The injected fuel is mixed with the intake air to form an air-fuel mixture, which is ignited to form a flame, and the injected fuel is continuously supplied to the flame to continue combustion. This combustion method starts ignition during fuel injection, and is referred to as normal combustion in this specification. [0004] In recent years, a new combustion method (such as Japanese Patent Documents 1 and 2) has been proposed. This combustion method ad...

AI Technical Summary

Problems solved by technology

Although after-treatment devices can be used to purify soot and NOx, it leads to lower fuel consumption and higher costs

[0020] In addition, in the premixed combustion of the above-mentioned single-stage injection, if the EGR is increased, the oxygen concentration will decrease and the flame will be more easily stalled. Therefore, the NOx reduction effect of EGR cannot be sufficiently obtained.

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