Direct injection spark ignition engine

摘要

A direct injection engine in which an injector (11) injects fuel toward a cavity (20) formed in a top surface of a piston (4) to produce a locally distributed mixture around a spark plug (12) is constructed such that the direction of a fuel spray ejected from the injector is varied during a fuel injection period to properly spread the mixture and prevent its local overrichness. The direct injection engine is provided with means for generating a swirl, for example, so that the fuel spray from the injector is directed toward the spark plug when the pressure in a cylinder is low in a compression stroke, and the fuel spray is deflected by the swirl away from the direction of the spark plug as the pressure in a cylinder increases.