Abstract: A fuel injector for the injection of fuel into the combustion chamber of an internal combustion engine includes a valve needle guided in a nozzle body, the valve needle being actuable by an actuator and acted upon by a restoring spring in such a manner that a valve-closure member which is in operative connection to the valve needle is retained in sealing contact against a valve-seat surface. Formed at a downstream-side end of the fuel injector is a projection which projects beyond the valve-closure member of the fuel injector.

Abstract: A fuel injector, in particular a fuel injector for fuel-injection systems of internal combustion engines, includes a first magnetic coil cooperating with a first armature, a second magnetic coil cooperating with a second armature, and a valve needle which is in force-locking connection with the first armature via a first flange and to the second armature via a second flange, to actuate a valve-closure member. A restoring spring acts upon the valve needle in a closing direction of the fuel injector. A first positioning spring, situated between the first flange and the first armature, acts upon the first armature in the closing direction of the fuel injector, while a second positioning spring, situated between the second flange and the second armature, acts upon the second armature in an opening direction of the fuel injector.

Abstract: A fuel injector, in particular a fuel injector for fuel-injection systems of internal combustion engines, has a piezoelectric or magnetostrictive actuator which actuates, via a hydraulic coupler a valve-closure member formed on a valve needle, the valve-closure member cooperating with a valve-seat surface to form a sealing seat. The coupler is made up of a pressure cylinder, a pressure-cylinder support joined to the pressure cylinder, and a pressure piston guided in this pressure cylinder, which form a pressure chamber; and of a coupler spring element between the pressure piston and the pressure cylinder which generates a prestressing force that forces the pressure piston out of the pressure cylinder.

Abstract: A fuel injector (1) for the injection of fuel into the combustion chamber of an internal combustion engine includes a valve needle (4) guided in a nozzle body (3), the valve needle (4) being actuable by an actuator (7) and acted upon by a restoring spring (9) in such a manner that a valve-closure member (5) which is in operative connection to the valve needle (4) is retained in sealing contact against a valve-seat surface (6). Formed at a downstream-side end (13) of the fuel injector (1) is a projection (14) which projects beyond the valve-closure member (5) of the fuel injector (1).

Abstract: A fuel injector (1), in particular a fuel injector (1) for fuel-injection systems of internal combustion engines, comprises a first magnetic coil (2) cooperating with a first armature (3), a second magnetic coil (4) cooperating with a second armature (5), and a valve needle (14) which is in force-locking connection with the first armature (3) via a first flange (12) and to the second armature (5) via a second flange (13), to actuate a valve-closure member. A restoring spring (17) acts upon the valve needle (14) in a closing direction of the fuel injector (1). A first positioning spring (15), situated between the first flange (12) and the first armature (3), acts upon the first armature (3) in the closing direction of the fuel injector (1), while a second positioning spring (16), situated between the second flange (13) and the second armature (5), acts upon the second armature (5) in an opening direction of the fuel injector (1).

Abstract: A fuel injector (1), in particular a fuel injector for fuel-injection systems of internal combustion engines has a piezoelectric or magnetostrictive actuator (14) which actuates, via a hydraulic coupler (35a) a valve-closure member (3) formed on a valve needle (2), the valve-closure member (3) cooperating with a valve-seat surface (5) to a sealing seat (6). The coupler (35a) is made up of a pressure cylinder (34), a pressure-cylinder support (35) joined to the pressure cylinder (34), and a pressure piston (33) guided in this pressure cylinder (35), which form a pressure chamber (37); and of a coupler spring element (38) between the pressure piston (33) and the pressure cylinder (34) which generates a prestressing force that forces the pressure piston (33) out of the pressure cylinder (34).