Abstract: A fuel injector for internal combustion engines, includes a base body, an injection housing and a fastening device. The fastening device includes at least one lock nut with an annular land and an annular shoulder on the injection housing. By means of the fastening device, the injection housing is braced axially against the base body. A fuel inlet and at least one valve element are also provided. To improve the seal between the base body and the injection housing, the fastening device has at least one annular face which is oriented toward the annular land of the lock nut and is curved convexly in the manner of a spherical-segmental face.

Abstract: A fuel injection device (10), in particular an injector, for internal combustion engines, includes a base body (12). Both an injection housing (14) and a fastening device (48) are also provided. The fastening device (48) includes at least one lock nut (16) with an annular land (32) and an annular shoulder (40) on the injection housing (14). By means of the fastening device (48), the injection housing (14) is braced axially against the base body (12). A fuel inlet (24) and at least one valve element (22) are also provided. To improve the seal between the base body (12) and the injection housing (14), it is proposed the fastening device (48) has at least one annular face which is oriented toward the annular land (32) of the lock nut (16) and is curved convexly in the manner of a spherical-segmental face (41).