US 6,484,689 B1 · Fuel injection control apparatus for a diesel engine

Abstract

A fuel injection control apparatus for a diesel engine (1) is provided that eliminates a torque step occurring when shifting from a pilot fuel injection mode to a normal injection mode. After finding a total fuel injection quantity QFIN per cycle (block 101), a pilot fuel injection quantity QPILOTB is subtracted therefrom to determine a pilot fuel injection quantity QPILOT and a main fuel injection quantity QMAIN (block 103). Corrected pilot fuel injection quantity QPILOTF and corrected main fuel injection quantity QMAINF are determined using a fuel temperature correction coefficient KQTHF and a pilot fuel injection thermal efficiency CEHPILOT (block 104) and a main fuel injection thermal efficiency CEHMAIN (block 105). The thermal efficiencies are established based on the respective injection timings. A change in torque does not occur because the change in the thermal efficiency caused by the injection timing is offset.

Claims19

Dependent claims

A fuel injection control apparatus for a diesel engine, comprising:

a sensing section configured to receive a signal indicative of selected operating condition of a diesel engine;
a fuel injection calculation section configured to calculate a pilot fuel injection quantity for a pilot injection and a main fuel injection quantity for a main injection that occurs following the pilot injection, in response to the signal indicative of the selected operating condition;
a thermal efficiency correction section configured to correct at least one the pilot fuel injection quantity and the main fuel injection quantity based on a respective thermal efficiency during the pilot injection and the main injection;
and
a fuel injector configured to carry out the pilot injection and the main injection in response to the pilot fuel injection quantity and the main fuel injection quantity at least one of which are corrected in the thermal efficiency correction section.

2 more elements

Dependencies are inferred from the claim text.

Fuel injection control apparatus for a diesel engine

Life of this patent

Fuel injection control apparatus for a diesel engine

Life of this patent

Abstract

Claims19