System for fuel injection control in an internal combustion engine

摘要

A system for fuel injection control in internal combustion engine is provided. Fuel is injected during exhaust stroke from a fuel injector for port injection upstream of an intake valve. In-cylinder temperature as the engine cylinder undergoes compression is predicted. Fuel is injected during intake stroke from the fuel injector to supply fuel to the inside of the cylinder upon determining that the predicated in-cylinder temperature is greater than a temperature beyond which pre-ignition is expected to happen.

主权项

1. A system for fuel injection control in an internal combustion engine for controlling a fuel injector, positioned upstream of an intake valve provided per each cylinder of the internal combustion engine, coupled to an admission path for admitting gas to the cylinder, comprising:
a fuel injector control function configured to inject fuel from the fuel injector during exhaust stroke of the cylinder when an exhaust valve opens; an in-cylinder temperature prediction function configured to predict in-cylinder temperature as the cylinder undergoes compression; a control modification function configured to modify control by the fuel injector control function so as to inject fuel from the fuel injector during intake stroke of the cylinder when the intake valve opens to supply fuel to the inside of the cylinder upon determining that the in-cylinder temperature as the cylinder undergoes compression which is predicted by the in-cylinder temperature prediction function is greater than a predetermined temperature beyond which pre-ignition is expected to happen; a difference calculation function configured to calculate, when the control modification function determines that the in-cylinder temperature as the cylinder undergoes compression which is predicted by the in-cylinder temperature prediction function is higher than the predetermined temperature beyond which pre-ignition is expected to happen, a difference between the in-cylinder temperature as the cylinder undergoes compression and the predetermined temperature beyond which pre-ignition is expected to happen; and wherein the control modification function modifies control by the fuel injector control function so as to inject fuel from the fuel injector during the intake stroke to supply fuel to the inside of the cylinder upon determining that the difference which is calculated by the difference calculation function is greater than a predetermined threshold, and modifies control by the fuel injector control function so as to inject fuel from the fuel injector during the exhaust stroke and to inject fuel from the fuel injector during the intake stroke immediately after the exhaust stroke to supply fuel to the inside of the cylinder upon determining that the difference which is calculated by the difference calculation function is less than or equal to the predetermined threshold.