Fuel injection nozzle for internal combustion engines

摘要

A fuel injection nozzle for internal combustion engines having a valve needle which enters an intermediate position in a retarded fashion and subsequently reaches its final position quickly. The valve needle is coupled in a positively-engaged manner with a supplementary body which as a result of its mass and/or hydraulically damps the movement of the valve needle over the course of a first stroke portion. At the end of this stroke portion, the supplementary body strikes a shoulder attached to the housing, whereupon the valve needle after the attainment of a notably higher fuel pressure, is separated from the supplementary body and translated quickly into its open position. In special cases, it is also possible for two supplementary bodies to be provided, which are uncoupled one after another from the valve needle and then again recoupled to the valve upon the closure of the valve. With an apparatus of this kind, the injection procedure can be adapted more freely than in the case of the known injection nozzles to a desired course.