Abstract: A fuel injector for the direct injection of fuel into the combustion chamber of an internal combustion engine includes a valve needle, which is arranged in a nozzle body, is actuable by an actuator and acted upon by a restoring spring such that a valve closure member, which is in operative connection to the valve needle and faces the combustion chamber, is kept in sealing contact on a valve seat surface in the non-actuated state of the actuator. A surface of the fuel injector has a concave design in a transition region between the nozzle body and the valve-closure member.

Abstract: A fuel injector is described for fuel injection systems in internal combustion engines that includes a magnet coil, an armature that is acted upon in a closing direction by a restoring spring, and a valve needle that is non-positively engaged with armature for actuating a valve closing body, which together with a valve seat surface forms a sealing seat, and armature with an inlet-side armature surface striking internal pole. A choke point is provided on inlet-side armature surface, and is formed by an annular, stepped prominence on inlet-side armature surface.

Abstract: A fuel injector for the direct injection of fuel into the combustion chamber of an internal combustion engine includes an actuator, which is encapsulated in a first sleeve and is sealed from an inner chamber of the fuel injector; a valve needle actuable by the actuator, which includes a valve-closure member cooperating with a valve-seat surface to form a sealing seat; and a locking spring, by which the valve needle is acted upon in such a manner that the valve-closure member is held in sealing contact at the valve-seat surface. An inflow-side end face of the first sleeve is dimensioned such that a linear deformation of the first sleeve, caused by the fuel pressure present at the inflow-side end face, is compensated by a linear deformation of the actuator and an activating piston extending the actuator.

Abstract: A fuel injector for fuel-injection systems of internal combustion engines having a piezoelectric or magnetostrictive actuator, includes a hydraulic coupler which actuates a valve-closure member (3) formed on a valve needle. The valve-closure member cooperates with a valve-seat surface to form a valve-sealing seat. The coupler includes a master piston and a slave piston which are guided in bores of a guide sleeve. Located between the master piston and the slave piston is a pressure chamber filled with a hydraulic fluid. A corrugated tube is positioned around the guide sleeve which is sealingly joined to the master piston at one end and to the slave piston at the other end, and which seals a supply chamber for the hydraulic fluid from a surrounding fuel chamber.

Abstract: A fuel injector for the direct injection of fuel into the combustion chamber of an internal combustion engine includes a piezoelectric or magnetostrictive actuator, a hydraulic coupler, the hydraulic coupler having a master piston and a slave piston that are connected to a pressure chamber, and the pressure chamber being filled with an hydraulic fluid. The pressure chamber is sealed from an actuator chamber by a first seal and from a valve interior chamber by a second seal.

Abstract: A fuel injector, in particular for direct injection of fuel into the combustion chamber of a mixture-compressing, spark-ignited internal combustion engine, includes a valve housing formed by a nozzle body, as well as a sealing ring, which seals the fuel injector against a cylinder head of the engine.

Abstract: A fuel injector, in particular, an injector for fuel injection systems of internal combustion engines, having an actuator, which cooperates with a valve needle, has a first valve closure member that is arranged on the valve needle, the valve closure member cooperating with a first valve seat surface on a valve body forming a first sealing seat. A second valve closure member cooperates with a second valve seat surface in the valve seat body forming a second sealing seat. The valve needle, or the first valve closure member, has a limit stop, against which, after a partial stroke of the valve needle, a counter limit stop of the second valve closure member strikes, lifting the second valve closure member from the second sealing seat in response to a further stroke of the valve needle.

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 for the direct injection of fuel into the combustion chamber of an internal combustion engine encompasses a piezoelectric or magnetostrictive actuator, a valve needle actuable by the actuator, the valve needle cooperating with a valve-closure member to form a sealing seat together with a valve-seat member, and a restoring spring by which the valve needle is acted on in a closing direction. The valve needle is pressure-equalized in that the force exerted by the fuel pressure on the valve needle in the opening direction is approximately equal to the force exerted by the fuel pressure on the valve needle in the closing direction.

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, particularly for direct injection of fuel into a combustion chamber of a mixture-compressing, spark-ignited internal combustion engine, includes an actuator, a valve needle actuatable by the actuator for actuation of a valve-closure member, which, together with a valve-seat surface forms a sealing seat, and a swirl disk which has at least one swirl channel. An elastic membrane is arranged upstream from the swirl disk in such a way that a metering cross-section of the at least one swirl channel is variable as a function of the fuel pressure prevailing in the fuel injector during operation.

Abstract: A fuel injector for fuel injection systems of internal combustion engines has a valve-closure member that is in working engagement with a valve needle and that coacts with a valve-seat surface positioned in an orifice of a valve-seat member to form a sealing seat. The fuel injector has at least one spray discharge opening positioned in the valve-seat member. Between the valve-seat surface and the spray discharge opening, a second surface that make a more acute angle with the center axis of the fuel injector than the valve-seat surface, is formed by the orifice of the valve-seat member. A closure element extension whose enveloping surface forms an obtuse angle with the contiguous contour of the valve-closure member is positioned at the downstream end of the valve-closure member.

Abstract: A fuel injector, in particular a fuel injector for fuel injection systems of internal combustion engines, has a piezoelectric or magnetostrictive actuator, a valve closing element that can be actuated by the actuator and that works together with a valve seat face to form a seal seat, and a temperature compensation device. The temperature compensation device has a housing that is elastically deformable along a direction of actuation of the actuator, and has at least one throttle that connects an interior space of the housing with a fuel inlet of the fuel injector. The cross-section of this throttle is dimensioned such that an entry and exit of fuel into the housing of the temperature compensation device is enabled when there is a temperature-caused change in length of components of the fuel injector.

Abstract: The invention relates among others to a method for producing outlet openings (32) in a valve, in particular a fuel injection valve. The injection valve has a fuel inlet (2), an excitable actuating device (1, 2, 19) by which a valve closing member (28) is movable, a fixed valve seat (27) embodied on a valve seat element (26), with which seat the valve closing member (28) cooperates to open and close the valve, and at least one outlet opening (32), as a fuel outlet, provided downstream of the valve seat (27). The at least one outlet opening 32 is produced in such a way that in a first method step, a through hole is created in the valve seat element (26), and in a second method step, from the ejection end of the through hole, an outlet region is created that is altered in shape and/or size and/or contour compared to the through hole.

Abstract: A fuel injector (1) for fuel injection systems of internal combustion engines has a solenoid (10), a valve needle (3) pressed in the closing direction by a return spring (23) to activate a valve closing member (4), which together with a valve seat surface (5) forms a sealing seat, and an armature (20) in friction-locking connection with a valve needle (3). A first guide sleeve (35) and a second guide sleeve (36) are connected to the valve needle (3). The armature (20) has radial play with respect to the valve needle (3) as a result of the central opening (34), the diameter of which is greater than the diameter of the valve needle (3).

Abstract: A fuel injector for fuel injection systems of internal combustion engines and a method of manufacturing same are described. The fuel injector includes a valve seat body into which a valve seat face is introduced, which cooperates with a valve closing body to form a sealing seat, and a nozzle body to which the valve seat body is fixedly connected. The valve seat body is insertable into the interior of the nozzle body and on its downstream side it has a partially spherical outside geometry, which rests on a bearing surface of a seat body recess in the nozzle body. Valve seat body is mounted so it can rotate relative to the nozzle body on the bearing surface until its position is finally secured, and it may be aligned by a centering mandrel.

Abstract: A fuel injection valve, in particular an injection valve for fuel injection systems of internal combustion engines, is made of a piezoelectric or magnetostrictive actuator and a valve closing body that can be set in motion by the actuator via a valve needle and that interacts with a valve seat surface to produce a seat. To compensate for the temperature expansion, at least one damping element made of a solid is present and exhibits an almost static behavior at a high deformation rate and is elastically or plastically deformable at a low deformation rate.

Abstract: A fuel injector (1), especially an injector for fuel injection systems of internal combustion engines, includes a first solenoid coil (5), which cooperates with the first armature (9), a valve needle (13) in a force-locking connection with the first armature (9) for actuating a valve-closure member (14), which together with a valve seat surface (15) forms a sealing seat, and a second solenoid coil (6). In this context, the first armature (9) is acted upon in a closing direction by a first resetting spring (11). A second armature (10) cooperates with the second solenoid coil (6) such that, when the first solenoid coil (5) and the second solenoid coil (6) are supplied with current, a limit stop body (18) that is connected with the valve needle (13) strikes against the second armature (10).

Abstract: A fuel injector (1) for the direct injection of fuel into the combustion chamber of an internal combustion engine encompasses an actuator (5), which is encapsulated in a first sleeve (4) and sealed from an inner chamber (25) of the fuel injector (1); a valve needle (19) actuable by the actuator (5), which includes a valve-closure member (23) cooperating with a valve-seat surface (24) to form a sealing seat; and a locking spring (22), by which the valve needle (19) is acted upon in such a manner that the valve-closure member (23) is held in sealing contact at the valve-seat surface (24). An inflow-side end face (29) of the first sleeve (4) is dimensioned such that a linear deformation of the first sleeve (4), caused by the fuel pressure present at the inflow-side end face (29), is compensated by a linear deformation of the actuator (5) and an activating piston (8) extending the actuator (5).

Abstract: A fuel injector, e.g., an injector for fuel injection devices in internal combustion engines, has a valve needle with a valve-closure member which cooperates with a valve seat surface in a valve seat body to form a sealing seat, in which the valve seat body has a plurality of injection orifices that are isolated from the fuel supply by sealing seat. The valve-closure member has a pressure element in a recess facing the valve seat body, which is pre-tensioned against the valve seat body by a spring which is supported on the valve-closure member and presses a disc spring against the valve seat body, in such manner that the disc spring covers at least one of the injection orifices, and the spring element uncovers this injection orifice when the tension exerted by the pressure element is removed.