VALVE CHARACTERISTIC CONTROL DEVICE FOR INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To provide a valve characteristic control device for an internal combustion engine capable of effectively suppressing generation of smoke in a cold engine condition under which adhesion of liquid fuel to an inner wall of a combustion chamber increase. SOLUTION: Premixed combustion during which vaporized fuel burns under a condition of premixed with air occurs at first as combustion of fuel during a predetermined period from beginning of engine start to a time when liquid fuel adheres the inner surface if the combustion chamber 3 in the cold engine condition. After that, diffusion combustion during which liquid fuel adhering the inner wall of the combustion chamber 3 is vaporized by combustion heat or the like during above mentioned premixed combustion and burns occurs. Open timing of an exhaust valve 21 is made close to start timing of diffusion combustion. Consequently, since the exhaust valve 21 opens to reduce temperature and pressure in the combustion chamber 3 and to quench flames in the combustion chamber 3 at transition from premixed combustion to diffusion combustion in the combustion chamber 3, duration of diffusion combustion causing generation of smoke is very short even if diffusion combustion occurs. COPYRIGHT: (C)2005,JPO&NCIPI