A method of controlling a fuel injection of a diesel engine for performing a plurality of fuel injections to cause a plurality of combustions inside a cylinder in one combustion cycle, is provided, which includes acquiring an oxygen concentration inside the cylinder, performing, on compression stroke, the plurality of fuel injections at substantially even injection intervals while increasing the injection intervals as the oxygen concentration decreases, and performing, after the plurality of fuel injections, another fuel injection including a larger injection amount than in the plurality of fuel injections, near a top dead center of the compression stroke.

A method of controlling a fuel injection of a diesel engine for performing a plurality of fuel injections to cause a plurality of combustions inside a cylinder in one combustion cycle, is provided, which includes acquiring an oxygen concentration inside the cylinder, performing, on compression stroke, the plurality of fuel injections at substantially even injection intervals while increasing the injection intervals as the oxygen concentration decreases, and performing, after the plurality of fuel injections, another fuel injection including a larger injection amount than in the plurality of fuel injections, near a top dead center of the compression stroke.

A fuel injection control apparatus for an internal combustion engine includes a low pressure fuel pump, a low pressure fuel passage, a high pressure fuel pump, a high pressure fuel passage, a fuel injection valve, a high pressure controller, and a low pressure controller. The low pressure controller calculates a feedforward correction amount that increases as a request injection amount of the fuel injection valve increases and an increase rate of the high pressure target value increases when a high pressure target value increases. The low pressure controller calculates a feedback correction amount based on a low-side pressure deviation when the high pressure target value increases. The low pressure controller controls driving of the low pressure fuel pump based on a sum of the feedforward correction amount and the feedback correction amount.

A fuel injection control apparatus for an internal combustion engine includes a low pressure fuel pump, a low pressure fuel passage, a high pressure fuel pump, a high pressure fuel passage, a fuel injection valve, a high pressure controller, and a low pressure controller. The low pressure controller calculates a feedforward correction amount that increases as a request injection amount of the fuel injection valve increases and an increase rate of the high pressure target value increases when a high pressure target value increases. The low pressure controller calculates a feedback correction amount based on a low-side pressure deviation when the high pressure target value increases. The low pressure controller controls driving of the low pressure fuel pump based on a sum of the feedforward correction amount and the feedback correction amount.

A spiral blade unit is disclosed, which generates less blade-sagging, deformation, or vibration, can be made of various material, can be made with light material, and can be installed easily in interconnecting spiral blades. The spiral blade unit includes a rotational axle and spiral blades with root portions attached along an outer circumferential surface of the rotational axle, and the spiral blades are interconnected to one another through a blade connector.

A method for operating a combustion engine is provided. A fuel injector is operated to perform a fuel injection, a sequence of pressure signals of the fuel rail pressure during the fuel injection is sampled and filtered and a total pressure difference between a first sample after a top dead center of the fuel pump and before the fuel injection has started and a chosen second sample after the injection and before a next pumping stroke is determined. A linear pressure slope at the second sample and a leakage pressure difference between the first sample and the second sample based on the linear pressure slope is calculated, leading to calculating an injection pressure difference as the difference between total pressure difference and the leakage pressure difference. With this, a value of a fuel quantity injected as a function of the injection pressure difference can be determined, while leakages are compensated.

A method for operating a combustion engine is provided. A fuel injector is operated to perform a fuel injection, a sequence of pressure signals of the fuel rail pressure during the fuel injection is sampled and filtered and a total pressure difference between a first sample after a top dead center of the fuel pump and before the fuel injection has started and a chosen second sample after the injection and before a next pumping stroke is determined. A linear pressure slope at the second sample and a leakage pressure difference between the first sample and the second sample based on the linear pressure slope is calculated, leading to calculating an injection pressure difference as the difference between total pressure difference and the leakage pressure difference. With this, a value of a fuel quantity injected as a function of the injection pressure difference can be determined, while leakages are compensated.

A high-pressure pump control device is applied to an internal combustion engine including a high-pressure pump supplied with fuel discharged from a low-pressure pump and an injector supplied with fuel discharged from the high-pressure pump. The high-pressure pump control device includes a prediction unit predicting whether a discharge quantity of the high-pressure pump exceeds a discharge quantity of the low-pressure pump and a restricting unit executing a discharge quantity restriction control to restrict a discharge quantity of the high-pressure pump not to exceed a predetermined value when the prediction unit predicts that a discharge quantity of the high-pressure pump exceeds a discharge quantity of the low-pressure pump.

A high-pressure pump control device is applied to an internal combustion engine including a high-pressure pump supplied with fuel discharged from a low-pressure pump and an injector supplied with fuel discharged from the high-pressure pump. The high-pressure pump control device includes a prediction unit predicting whether a discharge quantity of the high-pressure pump exceeds a discharge quantity of the low-pressure pump and a restricting unit executing a discharge quantity restriction control to restrict a discharge quantity of the high-pressure pump not to exceed a predetermined value when the prediction unit predicts that a discharge quantity of the high-pressure pump exceeds a discharge quantity of the low-pressure pump.

A fuel injection control apparatus for an internal combustion engine includes a low pressure fuel pump, a low pressure fuel passage, a high pressure fuel pump, a high pressure fuel passage, a fuel injection valve, a high pressure controller, and a low pressure controller. The low pressure controller calculates a feedforward correction amount that increases as a request injection amount of the fuel injection valve increases and an increase rate of the high pressure target value increases when a high pressure target value increases. The low pressure controller calculates a feedback correction amount based on a low-side pressure deviation when the high pressure target value increases. The low pressure controller controls driving of the low pressure fuel pump based on a sum of the feedforward correction amount and the feedback correction amount.