A valve assembly for an injection valve is disclosed, including a valve body with a cavity, a valve needle axially moveable in the cavity, the valve needle being fixedly connected to a retaining element which extends in radial direction and is arranged in an axial region of the valve needle facing away from the fluid outlet portion, and an armature being able to slide on the valve needle and acting on the needle by way of the retaining element. A conical spring is arranged between the retaining element and a top side of the armature facing the retaining element, biasing the armature away from the retaining element.

Various embodiments may include a method for actuating a fuel injector with a solenoid drive and a nozzle needle. The solenoid drive has a solenoid and a movable armature. The fuel injector has an idle stroke between the armature and the nozzle needle. An example method includes: applying a precharging current to the solenoid drive during a precharging phase to move the movable armature into mechanical contact with the nozzle needle; and applying a voltage pulse to the solenoid drive during a boost phase until the current intensity of the current flowing through the solenoid reaches a predetermined peak value.

A valve (or fuel injector), which provides that the valve-seat member exhibits high structural strength and fatigue strength under vibratory stresses, includes an excitable actuator for actuating a valve-closing member which, with a valve-seat face on the valve-seat member, forms a sealing seat, and injection openings which are downstream of the valve-seat face, the injection openings being in a center area of the valve-seat member projecting outwardly dome-like in the injection direction. The dome-like center area has a curved outer contour, the curvature in a radially inner section having a larger radius than the radius of the curvature in a radially outer section of the dome, which ends radially outside the mouth areas of all injection openings, in a recessed depression, that is followed radially outwardly by an axially projecting edge area of the valve-seat member. The fuel injector directly injects fuel into a combustion chamber of an engine.

A fuel injection valve includes a valve body, a coil, an inner fixed iron core that is arranged on an inner peripheral side of the coil, and an outer fixed iron core that is arranged on an outer peripheral side of the coil. The fuel injection valve also includes a movable element that is configured to be attracted to the inner fixed iron core and the outer fixed iron core, wherein the movable element is configured to be separable from the valve body and is configured to move the valve body.

A fuel injector includes a fuel valve including a valve needle and a valve seat for controlling a flow of fuel through the injector. The fuel injector also includes an electromagnetic actuator with a solenoid and an armature that lifts the valve needle from the valve seat in an opening direction while the solenoid is electrically energized. The fuel injector also includes a housing in which the valve needle and the armature are received such that they are displaceable in reciprocating fashion with respect to the housing and with respect to one another. A spring is arranged between the armature and the housing, for pushing the armature against the valve needle in the opening direction, wherein the spring provides a hysteretic relationship between force and displacement.

A fuel injection valve includes a valve body, a coil, an inner fixed iron core that is arranged on an inner peripheral side of the coil, and an outer fixed iron core that is arranged on an outer peripheral side of the coil. The fuel injection valve also includes a movable element that is configured to be attracted to the inner fixed iron core and the outer fixed iron core, wherein the movable element is configured to be separable from the valve body and is configured to move the valve body.

A valve for metering a fluid, for example, a fuel injection valve for an internal combustion engine, includes a valve-seat face, an electromagnetic actuator including an armature that includes a through-flow channel that opens with an outlet opening at an end face of the armature, a valve needle on which the armature is movably supported and that is operable using the armature, a valve-closing member that is actuatable by the valve needle and that cooperates with the valve-seat face to form a sealing seat, and a stop element that is mounted fixedly on the valve needle and that interacts with the at least one outlet opening of the at least one through-flow channel such that throttling takes place with respect to the least one through-flow channel when the armature is located with its end face at the stop element.

A valve assembly may include: a valve body with a longitudinal axis and a cavity; a valve needle; and a driving device for displacing the valve needle. In some embodiments, the valve needle comprises a disc element. The disc element and the driving device comprise mutually facing and radially extending coupling surfaces, the coupling surfaces having an overlapping area of at least 35% of the cross-sectional area of the cavity. The driving device takes the disc element with it for displacing the valve needle in the opening direction solely by means of hydraulic interaction between the coupling surfaces when the driving device is displaced in the opening direction. The coupling surface of the driving device engages in a form-fit connection with the coupling surface of the disc element for pushing the valve needle towards the closing position.

A mobile valve member designed to be arranged in the nozzle body of a fuel injector, extends along a main axis and includes a piston formed of a first male cylinder of effective diameter forming the top end of the mobile member and of a second cylinder provided with an internal cylindrical bore of the effective diameter and a shutoff member including a male cylindrical shaft of the effective diameter that fits slidingly in the internal bore, and of a member extending as far as a pointed end provided with a mobile seat and forming the bottom end of the mobile member. The mobile member is hydraulically balanced and the length between the top end and the bottom end thereof is variable as a result of the sliding of the cylindrical shaft in the internal bore of the piston.

The present disclosure relates to internal combustion engines. Various embodiments may include a fuel injection system for delivering fuel to an internal combustion engine. For example, fuel injector may include a valve body having a cavity; a valve needle with a retainer moving in the cavity; an actuator assembly comprising: a spring element next to the valve needle; an electro-magnetic coil; an armature element movable in the cavity; and an anti-bounce device. The armature element may be between the retainer portion of the valve needle and the anti-bounce device. The anti-bounce device may impose a spring force and a hydraulic force for dampening a movement of the armature element. The anti-bounce device may comprise a spring portion exerting the spring force to close the valve needle and a hydraulic damper portion integrally connected to the spring portion.