An accumulator type fuel injector system for an internal combustion engine and a method of operating said system

摘要

The invention provides an accumulator type fuel injector system (10) for an i.c. engine comprising an accumulator chamber (12) for containing fuel to be injected via an injector assembly (14). The accumulator chamber (12) is charged with fuel at an elevated pressure via a non-return valve (16) means under control of a solenoid valve means (20) also controlling the injector assembly (14). The arrangement is such that, when the accumulator chamber (12) is being vented via the injector assembly (14), means (30) associated with the chamber (12) subject it to additional venting when the pressure in said chamber (12) has decayed to a predetermined level. Thus, closure of a needle valve (24) and consequently termination of a fuel injection event is determined by fuel pressure which can be varied rather than constructional features of the injector.