| 摘要 |
PROBLEM TO BE SOLVED: To secure good startability even under a cold condition in an engine provided with a variable lift mechanism VVL capable of lifting intake valves 1, 2 by rocking cams 4, 5 and continuously changing lift by changing rocking angle of the rocking cams 4, 5, and increasing lift and retarding close timing of the intake valves 1, 2. SOLUTION: At a time of cold start, lifts of the intake valves 1, 2 are minimized and cranking is started under a condition where rotary resistance is low (steps S3, S4). After oil film is formed on a sliding part of the variable lift mechanism by cranking, lift of the intake valves 1, 2, filled quantity of intake air to a cylinder is increased to increase effective compression ratio and to enhance intake air flow in the cylinder, evaporation and atomization of fuel and mixing with air are promoted (step S12). Consequently, reduction of cranking resistance, ignitability of air fuel mixture and improvement of combustibility are compatibly materialized with appropriate balance and good startability is secured even under the cold condition. COPYRIGHT: (C)2007,JPO&INPIT
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