Patent ID: 7769525

Claim:
A control apparatus used for a homogeneous charge compression-ignited internal-combustion engine including an injector for injecting a fuel into a combustion chamber, an igniter for igniting the fuel that has been injected into the combustion chamber, an air intake valve provided at an air intake side of a cylinder constituted as part of the combustion chamber, the intake valve being adapted to control operational timing of the valve itself, an exhaust valve provided at an exhaust side of the cylinder and adapted to control operational timing of the exhaust valve itself, a throttle valve adapted to control the amount of air flowing into the combustion chamber, and a swirl control valve adapted to control the flow of the air into the combustion chamber, the control apparatus controls the internal-combustion engine with a spark-ignited combustion mode in which the fuel injected from the injector is ignited and burned by the igniter in order to operate the internal-combustion engine, and a homogeneous charge compression-ignited combustion mode in which the fuel injected from the injector is burned by utilizing an internal pressure increase of the cylinder in order to operate the internal-combustion engine, the control apparatus comprising: means for controlling the injection of the fuel from the injector, ignition by the igniter, opening and closing of the intake valve, opening and closing of the exhaust valve, opening and closing of the throttle valve, and an opening angle of the swirl control valve, the control means being adapted to switch engine operation from the spark-ignited combustion mode to the homogeneous charge compression-ignited combustion mode according to information on an operational state of the engine; wherein, upon completion of switching from the spark-ignited combustion mode to the homogeneous charge compression-ignited combustion mode, the control means advances ignition timing of the igniter relative to ignition timing in the spark-ignited combustion mode, and for reduced maximum increase rate of pressure inside the combustion chamber, adjusts at least one of control quantities relating to the fuel injection from the injector, the ignition by the igniter, the opening and closing of the intake valve, the opening and closing of the exhaust valve, the opening and closing of the throttle valve, and the opening angle of the swirl control valve.