Abstract: A fuel injection valve for use in an internal combustion engine includes a nozzle having a nozzle needle, a nozzle holder supporting the nozzle, first and second springs provided in the nozzle holder and determining valve opening pressures for initial injection and main injection, respectively, a first movable spring seat supported by the nozzle needle and supporting the first spring, and a second movable spring seat having a rod mounted thereon and supporting the second spring, the rod being disposed in spaced and opposed relation to the first movable spring seat. In the nozzle holder are formed first and second spring chambers with the first and second springs fitted therein, respectively. A stepped portion is provided between the first and second spring chambers. The nozzle holder has a reference surface at its end portion remote from the nozzle, with respect to which various portions of the injection valve are measured.

Abstract: A fuel injection valve wherein a threaded member is threadedly mounted in a nozzle holder casing assembly for displacement therein to adjust the setting force of a valve-opening pressure setting spring and a bolt member is provided for coupling a leakage fuel drain pipe to the casing assembly. Continuous gaps are formed between the threaded peripheral surfaces of the adjusting threaded member and the coupling bolt member and the associated threaded inner peripheral surfaces of the casing assembly, which serve as leakage fuel passages.