Exhaust gas purification system for internal combustion engine

摘要

Based on an engine speed and an engine load (e.g. a fuel injection amount for primary fuel injection), an injection timing (A) for diesel particulate filter (DPF) regeneration fuel injection is set such that a crank angle (or time period) after compression top dead center (TDC) is minimized in a range in which there is no increase in shaft torque of the engine. This improves regeneration efficiency of the DPF, and thus, reduces an increase in degree of oil dilution (mixture of fuel into engine oil) due to the DPF regeneration fuel injection.