FUEL INJECTOR

PURPOSE:To sufficiently secure a measuring time and an injection time by providing a magnetic circuit constituted of a first and a second movable member, a valve seat, a valve body, and a first through a third spring. CONSTITUTION:A fuel injector comprises a magnetic circuit constituted of a first movable member 24 forming a first magnetic gap 50 between a fixing core 18 and the same and a second movable member 29 forming a second magnetic gap 51 between the fixing core 18 and the same. The first movable member 24 is attracted by the fixing core 18, to be moved against a third spring 41. A valve body 24c of the first movable member 24 is seated in a valve seat 29a of the second movable member 29, thus cutting off the communication between a combustion chamber 26 and a mixing chamber 23. Since an attraction force is generated on the second magnetic gap 51 at this time, an outer opening valve 34 is left open, and the residual fuel staying in a first fuel passage 30, a second fuel passage 35, the mixing chamber 23 and a third fuel passage 37 is injected with high pressure air. A fuel measuring process and a fuel injection process are carried out simultaneously.