INTAKE SYSTEM FOR INTERNAL COMBUSTION ENGINE

摘要

An intake system for an internal combustion engine has a fuel injector disposed in an induction passage upstream of a pivotally mounted throttle plate having an idle position in which the throttle plate has upstream and downstream edge portions slightly spaced from the inner peripheral surface of the induction passage to define therewith narrow gaps for the passage of air and injected fuel particles. A bypass air passage is formed in the peripheral wall of the induction passage and has a downstream end open thereto to produce a jet of air directed toward the central zone of the downstream face of the throttle plate when in the idle position. The air jet is operative to compensate for the difference in pressure between a central space immediately downstream of the throttle plate and peripheral zones adjacent to the narrow gaps whereby whirling-up of air and fuel particles just downstream of the throttle plate and resultant formation of drops of liquid fuel can be prevented.