A fuel injection valve includes: a housing that includes an injection hole and a valve seat; a needle that includes a flange at a radially outer side of the needle and opens or closes the injection hole; a movable core that is installed on the valve seat side of the flange; a first spring that urges the needle toward the valve seat side; a second spring that urges the movable core toward an opposite side, which is opposite from the valve seat; and a limiting member that is installed on a radially outer side of the needle such that the limiting member enables movement of the movable core between the limiting member and the flange on the valve seat side of the flange. The limiting member includes an outside projection, which supports the second spring; and a tubular portion and an inside projection, which are contactable with the movable core.

A valve assembly for a fluid injector is disclosed. The valve assembly includes a valve body having a longitudinal axis, an armature, a valve needle having a needle tip and a damping element. The armature and the damping element include penetrating first openings in which the valve needle is arranged. The damping element is fixed to the valve needle and arranged between the armature and the needle tip with respect to the longitudinal axis to attenuate a movement of the valve needle relative to the valve body during the operation of the valve assembly.

A fluid metering valve includes a housing, an electromagnetic actuator that includes an armature that is separated from an inner wall of the housing by an annular gap, a throttle element connected to the armature or the housing and arranged in the annular gap to dampen a movement of the armature that is opposite to an opening direction, a valve seat surface, a valve closing body that cooperates with the valve seat surface to form a sealing seat, and a valve needle that (a) is actuatable by the actuator, (b) is arranged for actuating the valve closing body (c) extends through a borehole in the armature so that the armature is movably guidable on the valve needle, and (d) includes a stop arranged such that, during an actuation, the armature strikes against the stop in the opening direction to thereby open the sealing seat.

A fluid metering valve includes a valve needle that is actuatable by an electromagnetic actuator that includes an armature guided on and along a longitudinal axis of the valve needle with a movement limited by a stop surface on the valve needle. A projection of an edge of the stop surface extends into a projection plane, perpendicular to the longitudinal axis and at which the armature and stop surface are in contact temporarily during operation, through an opening of a conduit of the armature, dividing the opening into an inner surface on one side of the projection and an outer surface on the other side of the projection. A fluid exchange between inside and outside of an area between the stop surface and armature is via a path through the inner surface, conduit, and outer surface when the armature is in contact with the stop surface at the projection plane.

A valve for metering a fluid. An armature of the electromagnetic actuator is movable along a longitudinal axis of a valve needle, the movement of the armature relative to the valve needle being limited by a stop surface on the valve needle. The armature has a passage channel. The stop surface is on a stop element. The stop element and the armature are such that during operation there always remains an intermediate space, adjoining the valve needle, between the stop element and an end face of the armature facing the stop element. The stop surface lies, in a contact region, on the end surface of the armature facing the stop element when the armature and the stop surface come into contact during operation, the contact region being situated between the intermediate space and an opening of the passage channel when the armature and the stop surface come into contact.

Some embodiments include: a valve body; a valve needle; a calibration spring biasing the needle to close a fluid outlet; an armature to actuate the needle; and an armature stopper comprising an armature support, a circumferential side wall, and a circumferential clamping portion. The armature stopper is coaxial with the valve needle below the armature, facing the armature and providing a stop for the armature in the closing direction. The clamping portion includes a circumferential gutter formed by a base portion, an inner wall and an outer wall. The inner wall is part of the circumferential side wall with a smaller radial extension than the outer wall and is closer to the valve needle. The outer wall extends circumferentially around the inner wall to form a press-fit area for press-fitting the armature stopper into the valve body.

The present disclosure relates to fluid injection and the teachings thereof may be embodied in an injector. Some embodiments include an injector comprising: a valve with a valve body and a valve needle; an armature mechanically coupled to the valve needle for moving the valve needle away from a closing position; and a damping element. The valve needle moves in the valve body and seals the valve. The armature displaces the valve needle away from the closing position. The damping element comprises: a hydraulic chamber and a piston arranged to modify a fluid volume of the hydraulic chamber. The piston reduces the fluid volume of the hydraulic chamber when the valve needle moves away from the closing position. A flow restricting orifice hydraulically connects the hydraulic chamber to the cavity.

A fuel injector includes a collar, which may be formed of a porous, sintered material, the collar being located around the needle and allowing a restricted fluid pathway, such as orifices through the collar, between first and second volumes of fuel, the collar being located in a section of the nozzle body which has a greater cross-sectional area than the rest of the bore.

An injector for injecting fluid with a valve assembly including a valve body and a valve needle, the needle including an armature retainer and being operable to prevent and to enable injection of fluid, and with an electromagnetic actuator assembly, operable to exert a force for influencing a position of the valve needle, including a pole piece and an armature. The pole piece is positionally fixed with the valve body. The armature is operable to be axially displaced relative to the pole piece and to take along the armature retainer when being displaced towards the pole piece. A fluid channel is defined by the armature retainer constriction surface and the pole piece constriction surface. A hydraulic diameter of the fluid channel is at least twice at large when the valve needle is in a closing position compared to the hydraulic diameter at a maximum displacement away from the closing position.

A solenoid valve for controlling fluids, in particular, a fuel injection solenoid valve. The solenoid valve includes a valve member for opening or closing an opening, an armature for actuating the valve member, and an armature stop, via which a movement of the armature is delimitable. The armature includes an armature base body having a first armature lining, which is situated on the armature base body and which exhibits a lower hardness than the armature stop. Alternatively, the armature stop includes a stop base body having a first stop lining, which is situated on the stop base body and which exhibits a lower hardness than the armature. This makes it possible to dampen a movement of the armature.