STARTING DEVICE OF SPARK-IGNITION MULTI-CYLINDER ENGINE

摘要

A starting device of a spark-ignition multi-cylinder engine is provided. The device includes a multi-cylinder engine body having cylinders, fuel injection valves, ignition plugs, an intake valve drive mechanism for opening and closing intake valves, a hydraulic variable valve phase mechanism for changing a close timing of each intake valve, an engine-driven hydraulic pressure supply source for supplying a hydraulic pressure, and a start controller for controlling the fuel injection valves, the ignition plugs, and the variable valve phase mechanism. When the supplied hydraulic pressure is below a predetermined pressure, the variable valve phase mechanism locks the close timing. When an engine temperature in an engine-start is high, the start controller retards a fuel injection timing of the cylinder on intake stroke at an engine stopped timing and retards an ignition timing thereof. The start controller does not retard the close timing of the intake valve until the engine-start completes.

主权项

1. A starting device of a spark-ignition multi-cylinder engine, comprising:
a multi-cylinder engine body including a plurality of cylinders each having a piston reciprocatably fitted therein; fuel injection valves for injecting fuel into the respective cylinders; ignition plugs for igniting mixture gas inside the respective cylinders; an intake valve drive mechanism for opening and closing intake valves for introducing intake air into the respective cylinders, synchronized with the reciprocations of the respective pistons; a hydraulic variable valve phase mechanism for changing a close timing of each of the intake valves between a predetermined most advanced timing and a predetermined most retarded timing after an intake bottom dead center; an engine-driven hydraulic pressure supply source for supplying a predetermined hydraulic pressure to the variable valve phase mechanism; and a start controller for controlling the fuel injection valves, the ignition plugs, and the variable valve phase mechanism in an engine start, wherein when the supplied hydraulic pressure is lower than a predetermined value, the variable valve phase mechanism locks the close timing of the intake valve to a predetermined timing that is between the most advanced timing and the most retarded timing and enables a cold start of the engine; wherein when the engine in the engine start is in a high temperature state in which a temperature thereof is higher than a predetermined temperature, the start controller performs retard-setting on the cylinder that is on intake stroke at an engine stopped timing among the plurality of cylinders to set a fuel injection timing thereof to an early stage of expansion stroke, and the start controller retards an ignition timing of the cylinder to a timing in the early stage of the expansion stroke and after the fuel injection is completed, and wherein even after the engine start begins and the hydraulic pressure supplied to the variable valve phase mechanism exceeds the predetermined value, the start controller performs non-retard-setting on the intake valve to set the close timing thereof to the predetermined timing or earlier until the engine start is completed.