Injection control device of internal combustion engine

A fuel injection control device applied to an injector that has a valve body formed with a fuel injection hole, a valve member accommodated in the valve body for opening and closing the injection hole, and an actuator for driving the valve member such that the valve member reciprocates and that is structured to be able to continuously adjust an injection rate of the injector indicating a fuel injection quantity per unit time in accordance with an actuator operation signal to the actuator, the fuel injection control device comprising:

• a fuel pressure sensing section configured to sense a fuel pressure waveform indicating a transition of a fuel pressure fluctuation accompanying a predetermined injection of the injector;
• and
• an operation signal calculating section configured to calculate the actuator operation signal for approximating a predetermined injection parameter concerning the predetermined injection to a reference value of the parameter based on the fuel pressure waveform sensed by the fuel pressure sensing section, wherein the operation signal calculating section calculates the actuator operation signal concerning the predetermined injection during execution of the predetermined injection;
• and
• an operation signal setting section configured to set the actuator operation signal calculated by the operation signal calculating section as a command concerning the predetermined injection during the execution of the predetermined injection, wherein
• the operation signal calculating section calculates an integration value of an injection rate from an injection start to a predetermined timing of the predetermined injection, and corrects a waveform signal of the injection rate based on a deviation of the integration value and a reference value thereof to approximate a total injection quantity of one injection as the injection parameter to a reference value of the parameter,
• wherein the deviation of the integration value and the reference value thereof is determined upon determination that a maximum injection rate reach timing has been reached.