CYLINDER INJECTION TYPE INTERNAL COMBUSTION ENGINE

摘要

A cylinder injection type internal combustion engine wherein a recessed portion (22A) is formed in an upper surface of a piston (22) so as to produce and develop a vertical vortex current in which intake gas that is introduced into a combustion chamber (27) of the engine is directed from a lower side (21A) of a cylinder head (21) of the engine to the upper surface of the piston (22) and then from the upper surface of the piston (22) to the lower side (21A) of the cylinder head, and wherein a corner on an outlet side of the recessed portion (22A) where the vertical vortex current exits, is formed more bluntly than a corner of the recessed portion (22A) where the vertical eddy current enters, whereby fuel is directly injected into the combustion chamber (27). This cylinder injection type internal combustion engine can, in particular, stably burn thin fuel-air mixture in a stratified fashion on thereby reduce fuel consumption and, even in burning fuel-air mixture richer than the thin fuel-air mixture, it can ensure a high output, whereby it is possible to provide an internal combustion engine with high efficiency.