Fuel injection control system of internal combustion engine

A fuel injection control system of a compression ignition type internal combustion engine, the fuel injection control system comprising:

• state detecting means for detecting an operating state of the engine;
• and
• controlling means for controlling fuel injection based on the operating state of the engine, wherein
• the state detecting means includes timing measuring means for measuring ignition timing of the engine, and
• the controlling means includes:
• second feedback-controlling means for feedback-controlling fuel injection timing so that the ignition timing coincides with predetermined target timing;
• and
• prohibiting means for prohibiting the feedback control in a certain operation range, in which a maximum value of a cylinder pressure increases as the ignition timing of the engine advances and torque outputted by the engine increases as the ignition timing advances or is substantially constant even if the ignition timing advances.

A fuel injection control system of a compression ignition type internal combustion engine, the fuel injection control system comprising:

• state detecting means for detecting an operating state of the engine;
• and
• controlling means for controlling fuel injection based on the operating state of the engine, wherein
• the state detecting means includes pressure measuring means for measuring a maximum value of a cylinder pressure of the engine and timing measuring means for measuring ignition timing of the engine, and
• the controlling means includes:
• first feedback-controlling means for feedback-controlling fuel injection timing so that the cylinder pressure maximum value coincides with a predetermined target pressure value;
• second feedback-controlling means for feedback-controlling the injection timing so that the ignition timing coincides with predetermined target timing;
• and
• switching means for selecting the first feedback-controlling means in a first operation range, in which the cylinder pressure maximum value increases as the ignition timing advances and torque outputted by the engine increases as the ignition timing advances or is substantially constant even if the ignition timing advances, and for selecting the second feedback-controlling means in a second operation range, in which the cylinder pressure maximum value increases as the ignition timing advances and the torque decreases as the ignition timing advances.