Abstract: A fuel injection control device for an engine comprises a fuel injecting device for directly injecting fuel into a cylinder of the engine and being capable of changing fuel injection rate arbitrarily during injecting the fuel, a fuel supplying device for supplying high-pressure fuel to the fuel injecting device, and a control unit for controlling the fuel injecting device depending on an operating region of the engine so as to adjust a quantity of fuel to be injected into the cylinder of the engine, the control means reducing the fuel injection rate of the fuel injecting device once and subsequently increasing the fuel injection rate during the main injection that contributes to torque generation of the engine.

Abstract: A combustion control system of a diesel engine, which controls a fuel-injection timing by switching from one to another of a normal combustion mode, a premix combustion mode, and a transition mode of between these modes, and switches from the normal combustion mode to the transition mode if an intake oxygen density is equal to or lower than a predetermined value in the normal combustion mode.

Abstract: There are provided a diesel engine that injects fuel into air compressed in cylinders and combusts the fuel by spontaneous ignition, and a control unit that sets the fuel injection timing to an earlier time point than the compression top dead center to premix air and fuel and combusts the air-fuel mixture compressed in the cylinders by spontaneous ignition. The control unit injects the fuel to be injected in an early stage in a plurality of stages according to the operation state of the engine and individually adjusts the injection pressures of their respective stages according to the gas density and the gas temperature in the corresponding cylinder.

Abstract: There are provided a diesel engine that injects fuel into air compressed in cylinders and combusts the fuel by spontaneous ignition, and a control unit that sets the fuel injection timing to an earlier time point than the compression top dead center to premix air and fuel and combusts the air-fuel mixture compressed in the cylinders by spontaneous ignition. The control unit injects the fuel to be injected in an early stage in a plurality of stages according to the operation state of the engine and individually adjusts the injection pressures of their respective stages according to the gas density and the gas temperature in the corresponding cylinder.