Perfected electromagnetic metering valve for a fuel injector

The metering valve (24) has a shutter (44) for a discharge conduit (43), and an electromagnet (26) for controlling an armature (27) disconnected from a respective stem (47) and sliding along the stem (47) by means of a respective sleeve (48); the stem (47) is guided by a bush (53) and pushed by a first spring (52) to keep the shutter (44) in the closed position; and the armature (27) is held axially resting against the stem (47) by a second spring (64) preloaded between the armature (27) and an annular shoulder (63) of the stem (47), so as not to affect the action of the first spring (52).