Controller for direct injection engine
AssigneeDenso Corporation
InventorMasaomi Inoue
Life of this patent
Estimating the term…
Abstract
When an engine is at starting or at cold state, a closing time of an exhaust valve is set before an intake top dead center to close the exhaust valve early. An exhaust residual gas is compressed by a cylinder to raise an inner cylinder temperature. A pre-fuel injection is performed from a time of closing the exhaust valve to a time of the intake top dead center in such a manner that the pre-injected fuel is combusted to raise the inner cylinder temperature. This increase in temperature expedites an atomization of fuel injected at a main fuel injection. A wet amount of fuel is reduced and HC emission is also reduced.
Claims11
A controller for a direct injection engine in which a fuel is injected into a cylinder directly, the controller comprising:
- an exhaust valve control means for performing an exhaust valve early closing control in which a closing timing of an exhaust valve is set before an intake top dead center at least when the engine is at starting and/or at cold state in order to raise an inner cylinder temperature;
- and
- a fuel injection control means for performing a pre-fuel injection from a time of closing the exhaust valve to a time of the intake top dead center while the exhaust valve early closing control is performed, and performing a main fuel injection in a suction stroke and/or a compression stroke.
A controller for a direct injection engine in which a fuel is injected into a cylinder directly, the controller comprising:
- an exhaust valve control means for performing an exhaust valve early closing control in which a closing timing of an exhaust valve is set before an intake top dead center at least when the engine is at starting and/or at cold state;
- a fuel injection control means for performing a pre-fuel injection from a time of closing the exhaust valve to a time of the intake top dead center while the exhaust valve early closing control is performed, and performing a main fuel injection in a suction stroke and/or a compression stroke;
- and
- an ignition control means for retarding an main ignition timing corresponding to the main fuel injection after the pre-fuel injection relative to an ignition timing after a warm-up of the engine white the exhaust valve early closing control and the pre-fuel injection are performed.
Dependencies are inferred from the claim text.