START CONTROL DEVICE OF HOMOGENEOUS-CHARGE COMPRESSION IGNITION ENGINE

摘要

When a predetermined restart condition is satisfied after an engine is automatically stopped, whether or not a piston of a stopped-in-compression-stroke cylinder which is in a compression stroke falls within a specific range set at a bottom dead center side of a predetermined upper limit position is determined. When the piston of the stopped-in-compression-stroke cylinder falls within the specific range, a first compression start is executed in which fuel is injected from an injector into the stopped-in-compression-stroke cylinder for the first time and is then self-ignited. In the first compression start, a start timing of a first fuel injection operation with respect to the stopped-in-compression-stroke cylinder is set to be earlier as a stop position of the piston of the cylinder gets closer to the bottom dead center within the specific range.

主权项

1. A start control device provided at a homogeneous-charge compression ignition engine,
the homogeneous-charge compression ignition engine including a plurality of cylinders, pistons provided at the respective cylinders so as to reciprocate, and injectors configured to inject fuel to the respective cylinders, the homogeneous-charge compression ignition engine performing homogeneous-charge compression ignition combustion in which the fuel injected into the cylinder from the injector before a compression top dead center is mixed with air and is then self-ignited by compression of the piston, the start control device comprising: an automatic stop control portion configured to automatically stop the engine when a predetermined automatic stop condition is satisfied; a stop position determining portion configured to determine whether or not the piston of a stopped-in-compression-stroke cylinder that is the cylinder which is in a compression stroke at the automatic stop of the engine falls within a specific range set at a bottom dead center side of a predetermined upper limit position; and a restart control portion configured to execute a first compression start when it is determined that the piston of the stopped-in-compression-stroke cylinder is stopped within the specific range and a predetermined restart condition is satisfied, the first compression start being the start in which the fuel is injected into the stopped-in-compression-stroke cylinder from the injector for the first time and is then self-ignited, and combustion is restarted from when the compression stroke is achieved for the first time in the entire engine, wherein the restart control portion sets a start timing of a first fuel injection operation with respect to the stopped-in-compression-stroke cylinder to be earlier as a stop position of the piston of the stopped-in-compression-stroke cylinder gets closer to the bottom dead center within the specific range.