SPARK IGNITION TYPE ENGINE

摘要

PROBLEM TO BE SOLVED: To provide a spark ignition type engine capable of avoiding the generation of knocking while suppressing the deterioration of fuel economy as much as possible. SOLUTION: This spark ignition type engine for combusting the air-fuel mixture in a combustion chamber 4 by spark ignition of a spark plug 9 arranged in the combustion chamber 4 and the following flame propagation comprises a passage 15 communicating with the combustion chamber 4 and an opening and closing valve 14 for opening and closing the passage 15. The opening and closing valve 14 is laid in an opened state for a prescribed period after the execution of spark ignition to deliver a part of the working gas in the combustion chamber 4 out of the combustion chamber.