| 摘要 |
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. A set screw is threadedly fitted in a tapped bore formed therein and having a contact surface disposed in contact with the reference surface. A first shim is interposed between the first spring and an end face of the stepped portion and determines the setting force of the first spring, a second shim between the other end face of the stepped portion and the second movable spring seat and determines the lifting amount of the nozzle needle during the initial injection, and a third shim between the second spring and an end face of the set screw and determines the setting force of the second spring.
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