Fuel swirl generation type fuel injection valve and direct fuel injection type spark ignition internal combustion engine mounted with the fuel injection valve

摘要

A fuel injection valve includes a fuel swirl generation device, a main fuel injection hole having a comparatively large diameter, and a subsidiary fuel injection hole having a comparatively small diameter. The inclination of the main fuel injection hole with respect to an axis of the fuel injection valve is small so that a fuel swirl remains in the fuel injected therethrough. The inclination of the subsidiary fuel injection hole is great so that the swirl operates so as to push out the fuel through the subsidiary fuel injection hole. The fuel injected through the main fuel injection hole spreads due to the centrifugal force acting on the swirling fuel without depending on an intake gas swirl. The fuel injected through the subsidiary fuel injection hole has a strong penetrating force and can reach the vicinity of a spark plug. This improves ignition without depending on an intake gas swirl. Thus, good combustion is obtained over an entire operation range of a direct fuel injection type engine.