SPARK IGNITION TYPE RECIPROCATING ENGINE

摘要

PROBLEM TO BE SOLVED: To reduce inverse torque becoming large in a stratified combustion state, and to improve fuel economy in a spark ignition type reciprocating engine 1 for performing stratified combustion in a leaner state than the stoichiometric air-fuel ratio in the average air-fuel ratio of a combustion chamber by directly injecting fuel into the combustion chamber in a compression stroke of a cylinder by an injector when existing in relatively low load side and low rotation side preset operation areas (A) (B). SOLUTION: The cylinder center line (z) of the engine 1 and the axis (x) of a crankshaft 17 are offset so that the cylinder center line (z) is positioned on the rear side more than the crank axis (x) in the rotational direction of the crankshaft 17 in an intermediate position of the crankshaft 17 and the cylinder 2 when viewed along the axis (x) of the crankshaft 17.