PCT No. PCT/DE88/00176 Sec. 371 Date Dec. 11, 1989 Sec. 102(e) Date Dec. 11, 1989 PCT Filed Mar. 22, 1988 PCT Pub. No. WO88/09869 PCT Pub. Date Dec. 15, 1988.Fuel injection nozzle for internal combustion engines, in which a pre-injection is effected with directed fuel sprays and then a main injection is effected with an additional fuel umbrella spray. The individual phases are to run in exact timed sequence and the main injection is to be separated from the pre-injection by way of a pressure step. For this purpose, a valve sleeve (34) is placed on a valve needle (18) which opens in the flow direction of the fuel and is provided with a closing head (20), the valve sleeve (34) being pressed, according to the invention, by an additional spring (50) against the closing head (20) with which it controls an annular valve gap for the umbrella spray. The valve sleeve (34) is also provided with lateral spray openings (62) through which the directed sprays exit during the pre-stroke in which the valve sleeve (34) moves with the valve needle (18) under the influence of the additional spring (50). After the pre-stroke, the valve sleeve (34) is prevented from further movement, so that the additional spring (50) is neutralized and the valve gap is opened for the umbrella spray.
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