Patent ID: 8930118
Filing Date: 2015-01-06
Classification: F02B,F02D,F02M,Y02T

Abstract:
1. An engine control system designed to allow homogeneous-charge compression ignition combustion to be performed in an HCCI region defined as an engine operating region including at least a partial-load range of an engine, comprising: a variable lift mechanism adapted to variably set a lift amount of an intake valve; a switching mechanism adapted to be capable of switching between allowing an exhaust valve to be opened both during an exhaust stroke and during an intake stroke, and allowing the exhaust valve to be opened only during the exhaust stroke; and a valve controller adapted to drive the variable lift mechanism and the switching mechanism to control respective opening/closing operations of the intake valve and the exhaust valve, wherein the HCCI region is divided into a plurality of load zones including a low load zone, and a medium load zone in which the engine load is higher than in the low load zone, and wherein the valve controller is operable: in the low load zone of the HCCI region, to set the lift amount of the intake valve to a first predetermined value and allow the exhaust valve to start being opened during the intake stroke at a given timing later than an opening timing of the intake valve; and in the medium load zone of the HCCI region, to gradually increase the lift amount of the intake valve up to a second predetermined value greater than the first predetermined value, along with an increase in the engine load.