| 摘要 |
PURPOSE:To obtain an excellent ignitability in a low speed and/or under a low load by providing a recessed dense air-fuel mixture sump formed in the side wall of an ignition chamber near an ignition plug to temporarily reserve dense air-fuel mixture in the sump after the completion of a fuel injection. CONSTITUTION:An ignition chamber 8 open to a combustion chamber 4 is cylindrically formed and fuel injected from a fuel injection valve 9 is fed into the combustion chamber 4 through the ignition chamber 8. An ignition plug 10 is provided between the combustion chamber 4 and the fuel injection valve 9 so as to face the ignition chamber 8. An annularly recessed dense air-fuel mixture sump 12 is formed in the side wall of the ignition chamber 8 and near a sparking position 11 of the top of the ignition plug 10. The sump 12 reserves, in excess, dense air-fuel mixture staying in the ignition chamber 8. Therefore, even when the amount of injected fuel is very small, the dense air-fuel mixture after the completion of fuel injection is temporarily reserved in the sump 12, whereby a sure ignition is conducted, by forcing the ignition plug to make a spark. |
